BUSCH R50160D User manual

Installation and Operating
Instructions
Vacuum pumps
R 5 0160 D / R 5 0202 D / R 5 0250 D / R 5 0302 D
Ateliers Busch S.A.
Zone industrielle
2906 Chevenez
Switzerland
0870524627 / 040106 / Modifications reserved

Table of Contents
Introduction.............................2
Product description .........................3
Use ................................3
Principle of operation .......................3
Oil Circulation ..........................4
Cooling..............................4
Operational Options / Use of Optionally Available Equipment ..4
On/Off switch ..........................4
Safety ................................4
Intended use ...........................4
Safety notes ...........................4
Emission of Oil Mist .......................4
Noise Emission ..........................5
Transport ..............................5
Transport in Packaging ......................5
Transport without Packaging ...................5
Storage ...............................5
Short-term Storage ........................5
Conservation ...........................5
Commissioning after conservation ...............6
Installation and Commissioning ..................6
Installation prerequisites .....................6
Mounting Position and space .................6
Suction Connection ......................6
Discharge connection .....................6
Electrical connection / Controls ................7
Heat exchanger (water/ oil) (accessory) .............7
Connecting cooling water ...................7
Installation ............................7
Mounting ...........................7
Connecting electrically .....................7
Connecting Lines/Pipes ....................8
Filling Oil ...........................8
Recording of Operational Parameters .............8
Operation Notes .........................9
Application...........................9
Conveying Condensable Steams ................9
Maintenance ............................9
Maintenance Schedule .....................10
Monthly: ..........................10
Every 6 Months: ......................10
Yearly: ...........................10
Every 500 - 2000 Operating hours (see “Oil Life”).....10
Every 16000 Operating hours, at the latest after 4 Years: . 10
Checking the oil.........................10
Checking the level ......................10
Topping up Oil ........................10
Checking the Colour of the Oil ................10
Oil Life .............................10
Oil and Oil Filter Change ....................11
Draining Used Oil.......................11
Flushing the vacuum pump ..................11
Cleaning of the level switch..................11
Replacing the Oil Filter ....................11
Filling in Fresh Oil.......................11
Exhaust Filter ..........................11
Check during operation....................11
Assessment ..........................12
Change of the exhaust filters .................12
Removing the exhaust filters ................12
Inserting the Exhaust Filters ................12
Gas ballast ...........................12
Inlet flange ...........................12
Fan cover ............................12
Motor cover...........................12
Overhaul .............................13
Removal from Service .......................13
Temporary Removal from Service ................13
Recommissioning ........................13
Dismantling and Disposal ....................13
Troubleshooting ..........................14
Exploded view ...........................19
Spare parts ............................20
Wearing parts kit ........................21
Accessories ...........................21
Oil.................................22
Technical data ...........................23
EC Declaration of Conformity ...................24
Busch – All over the World in Industry ..............26
Introduction
Page 2
Introduction
Congratulations on your purchase of the Busch vacuum pump. With
watchful observation of the field’s requirements, innovation and steady
development Busch delivers modern vacuum and pressure solutions
worldwide.
These operating instructions contain information for
–product description,
–security,
–transport,
–storage,
–installation and commissioning
–maintenance,
–overhaul,
–trouble shooting
of the the vacuum pump.
For the purpose of these instructions, “handling” the vacuum system
means the transport, storage, installation, commissioning, influence on
operating conditions, maintenance, troubleshooting and overhaul of
the vacuum system.
Prior to handling the vacuum system, these operating instructions
shall be read and understood. If anything remains to be clarified
please contact your Busch representative!
Keep these operating instructions and, if applicable, other pertinent
operating instructions available on site.

Product description
Use
The vacuum pump is intended for
–the suction
of
–air and other dry, non-aggressive, non-toxic and non-explosive ga-
ses.
Conveying media with a higher density than air leads to an increased
thermal and mechanical load on the vacuum pump and is permissible
only after prior consultation with Busch.
Max. allowed temperature of the inlet gas:
See “Oil, Ambient temperature range”
In case the vacuum pump is equipped with a gas ballast (optional), wa-
ter vapour within the gas flow can be tolerated within certain limits
(see “Installation and Commissioning, Operating Notes, Conveying
Condensable Vapours”). The conveyance of other vapours shall be
agreed upon with Busch.
The vacuum pump is intended for the placement in a non-potentially
explosive environment.
The vacuum pump is thermally suitable for continuous operation.
The vacuum pump is ultimate pressure proof.
Principle of operation
The vacuum pump works on the rotating vane principle.
A circular rotor (o,15) is positioned centrically on the shaft of the va-
cuum pump. The shaft of the vacuum pump is driven by the drive mo-
tor shaft by means of a flexible coupling.
The rotor (o, 15) rotates in an also circular, fixed cylinder(1), the cen-
treline of which is offset from the centreline of the rotor such that the
rotor and the inner wall of the cylinder almost touch along a line. Va-
nes (n,22), sliding in slots in the rotor, separate the space between the
rotor and the cylinder into chambers. At any time gas is sucked in and
at almost any time ejected. Therefore the vacuum pump works almost
pulsation free.
In order to avoid the suction of solids, the vacuum pump is equipped
with a mesh screen (h,261) in the suction connection.
In order to avoid reverse rotation after switching off, the vacuum pump
is equipped with a non-return valve (251-254).
NOTE: This valve shall not be used as a non-return valve or shut-off
valve to the vacuum system and is no reliable means to prevent suction
of oil into the vacuum system while the vacuum pump is shut down.
In case the vacuum pump is equipped with a gas ballast (optional):
Product description
Page 3
hag
on
f
mijkdp
lb
aSuction connection
bGas discharge
cRadial fan
dOil filter
eNameplate
fOil mist separator
gDischarge valve
hMesh screen
iOil sight glass
j Oil drain plug
kOil fill plug
lExhaust filter
mLevel switch
nRotor vanes
oRotor
pOil

Through the gas ballast valve (470-480) a small amount of ambient air
is sucked into the pump chamber and compressed together with the
process gas. This counteracts the accumulation of condensates from
the process gas inside the vacuum pump (see also “Operation Notes”).
Gas ballast version with ball valve:
The gas ballast line can be closed partially or completely by means of a
ball valve (477).
In order to improve the operating characteristics the outlet of the pump
chamber is equipped with a spring loaded valve (g,159).
Oil Circulation
The vacuum pump requires oil to seal the gaps, to lubricate the va-
nes(n,22) and to carry away compression heat.
The oil reservoir is located on the pressure side of the vacuum pump
(i.e. high pressure) at the bottom of the bottom chamber of the oil se-
parator (f,75).
The feed openings are located on the suction side of the vacuum pump
(i.e. low pressure).
Forced by the pressure difference between pressure side and suction
side oil is being drawn from the oil separator (f,75) through the oil sup-
ply lines and injected on the suction side.
Together with the sucked gas the injected oil gets conveyed through
the vacuum pump and ejected into the oil mist separator (f,75). Oil
that separates before the exhaust filter accumulates at the bottom of
the bottom chamber of the oil separator (f,75).
Oil that is separated by the exhaust filter (l,120) accumulates at the
bottom of the upper chamber of the oil separator (f,75).
The flow resistance of the exhaust filters (l,120) causes the inside of
the exhaust filters (which is connected to be bottom chamber of the oil
separator) to be on a higher pressure level than the outside of the ex-
haust filters (i.e. the upper chamber of the oil separator). Because of
the higher pressure in the bottom chamber it is not possible to let oil
that drips off the exhaust filters simply flow down to the bottom
chamber.
Therefore the oil that accumulates in the upper chamber is sucked by
the level switch (m,194) through the oil return line (290) right to the
suction connection (250).
Cooling
The vacuum pump is cooled by
–the ambient air around the vacuum pump, including oil mist sepa-
rator (f,75)
–the air flow from the fan wheel (400)
–the conveyed gas
–the air flow from the fan wheels (321,322) on the shaft of the va-
cuum pump
Operational Options / Use of
Optionally Available Equipment
In order to facilitate the start of the pump, an offloading valve (optio-
nal) with an exhaust line can be installed.
To control the oil level in the oil mist separator, an oil level switch is
mounted in the oil mist separator (as operational option).
In case of unfavourable temperature conditions, a heat exchanger (wa-
ter-oil) can be mounted as a complementary cooling (optional).
To suck condensable vapours, a gas ballast valve (optional) can be ins-
talled in the cylinder cover at fan side. To increase the capacity of va-
pours, another gas ballast valve can be installed in the cylinder cover at
the motor side. The valve can open or close the gas ballast during the
operation of the pump.
In order to ensure the best ultimate pressure during the process, a sole-
noid valve (optional) can be installed before the gas ballast valve. The
solenoid valve can be used as a purge at the end of the process.
On/Off switch
The vacuum pump comes without on/off switch. The control of the
vacuum pump is to be provided in the course of installation
Safety
Intended use
DEFINITION: : For the purpose of these instructions, “handling” the
vacuum pump means the transport, storage, installation, commissio-
ning, influence on operating conditions, maintenance, troubleshooting
and overhaul of the vacuum pump.
The vacuum pump is intended for industrial use. It shall be handled
only by qualified personnel.
The allowed media and operational limits according to the “Product
Description” and the “Installation Prerequisites” of the vacuum pump
shall be observed both by the manufacturer of the machinery into
which the vacuum pump is to be incorporated and by the operator.
The maintenance instructions shall be observed.
Prior to handling the vacuum pump these operating instructions shall
be read and understood. If anything remains to be clarified please
contact your Busch representative!
Safety notes
The vacuum pump has been designed and manufactured according to
the state-of-the-art. Nevertheless, residual risks may remain. These
operating instructions inform about potential hazards where appro-
priate. Safety notes are tagged with one of the keywords DANGER,
WARNING and CAUTION as follows:
DANGER
Disregard of this safety note will always lead to accidents with fa-
tal or serious injuries.
WARNING
Disregard of this safety note may lead to accidents with fatal or se-
rious injuries.
CAUTION
Disregard of this safety note may lead to accidents with minor inju-
ries or property damage.
Emission of Oil Mist
CAUTION
The non-OEM spares market offers exhaust filters that are geome-
trically compatible with Busch - vacuum pumps, but do not feature
the high retention capacity of genuine Busch-exhaust filters.
Increased risk of damage to health.
In order to keep the emission on the lowest possible level only ge-
nuine Busch-exhaust filters shall be used.
The oil in the process gas is separated to the greatest possible extent,
but not perfectly.
CAUTION
Aspiration of gas conveyed by the vacuum pump over extended pe-
riods can be harmful.
The room into which the gas conveyed by the vacuum pump is dis-
charged must be sufficiently vented.
Safety
Page 4

NOTE: The possibly sensible smell is not caused by droplets of oil,
though, but either by gaseous process components or by readily vola-
tile and thus gaseous components of the oil (particularly additives).
Noise Emission
For the sound pressure level in free field according to EN ISO 2151, see
“Technical Data”.
CAUTION
The vacuum pump emits noise of high intensity.
Risk of damage to the hearing.
Persons staying in the vicinity of a non noise insulated vacuum
pump over extended periods shall wear ear protection.
Transport
Transport in Packaging
Packed on a pallet the vacuum pump is to be transported with a for-
klift.
Transport without Packaging
In case the vacuum pump is bolted to a pallet or a base plate:
◆Remove the bolting between the vacuum pump and the pal-
let/base plate
CAUTION
Do not walk, work or stand under suspended loads.
NOTE: The position of the eyebolt (391) fits to the centre of gravity of
a vacuum pump incl. drive motor (400). If a vacuum pump without
drive motor is to be lifted, attach another belt/rope at a suitable point.
●Attach lifting gear securely to the eyebolt (391) on the cylinder.
●Attach lifting gear to a crane hook with safety latch.
●Lift the vacuum pump with a crane hook.
In case the vacuum pump was bolted to a pallet:
◆Remove the stud bolts from the rubber feet.
CAUTION
Tilting a vacuum pump that is already filled with oil can cause large
quantities of oil to ingress into the cylinder.
Starting the vacuum pump with excessive quantities of oil in the cy-
linder will immediately break the vanes and ruin the vacuum pump.
Once the vacuum pump is filled with oil it shall not be lifted
anymore.
●Prior to every transport make sure that the oil is drained
Storage
Short-term Storage
Version with gas ballast device with ball-cock:
●Make sure that the ball-cock (477) of the gas ballast device
(470-480) is closed
●Make sure that the suction connection/gas inlet and the gas dis-
charge/pressure connection are closed (leave the provided plugs
in)
●Store the vacuum pump
–if possible in original packaging,
–indoors,
–dry,
–dust free
–vibration free
Conservation
In case of adverse ambient conditions (e.g. aggressive atmosphere, fre-
quent temperature changes) conserve the vacuum pump immediately.
In case of favourable ambient conditions conserve the vacuum pump if
a storage of more than 3 months is scheduled.
During the factory tests, the vacuum pump inside has been completely
in contact with oil. In case of favourable ambient conditions, it is not
necessary to the pump with conservation oil . In case of unfavourable
storage conditions, the vacuum pump draining with conservation oil is
advised. If anything remains to be clarified please contact your Busch
representative!
●Make sure that the oil is drained (see “Maintenance, Oil Change,
Draining Used Oil”)
Version with gas ballast device with ball-cock:
●Make sure that the ball-cock (477) of the gas ballast device
(470-480) is closed
●Fill in conservation oil in small quantities by the suction connection,
observe the oil type and the given quantity in the tables below:
Oil Type
Renolin MRX 68, P/N 0831 512 575
(or a conservation oil from same quality)
Pump type Conservation oil quantity
R 5 0160 D
2 litres
R 5 0202 D
R 5 0250 D
R 5 0302 D
●Wrap PTFE-tape around the thread of the suction connection
●Firmly close the suction connection with a plug.
CAUTION
Operation with a gas discharge/pressure connection closed will da-
mage the vacuum pump.
Make sure that the gas discharge is open.
CAUTION
During operation the surface of the vacuum pump may reach tem-
peratures of more than 70°C.
Risk of burns!
Do not touch the hot housing.
●Electrically connect the vacuum pump (see “Installation and Com-
missioning, Installation, Connect Electrically”)
●Let the vacuum pump run for at least half an hour
●Switch the vacuum pump off
●Drain the conservation oil (see “Maintenance, Oil Change, Drai-
ning Used Oil”)
●Wrap PTFE-tape around the thread of a plug
●Firmly insert the plug into the discharge connection
●Make sure that all ports are firmly closed ; seal all ports that are not
with PTFE-tape, gaskets or o-rings with adhesive tape.
NOTE: VCI stands for “Volatile Corrosion Inhibitor”. VCI-products
(film, paper, cardboard, foam) evaporate a substance that condenses in
Transport
Page 5

molecular thickness on the packed good and by its electro-chemical
properties effectively suppresses corrosion on metallic surfaces. Howe-
ver, VCI-products may attack the surfaces of plastics and elastomers.
Seek advice from your local packaging dealer! Busch uses CORTEC VCI
126 R film for the overseas packaging of large equipment.
●Wrap the vacuum pump in VCI film
●Store the vacuum pump
–if possible in original packing,
–indoors,
–dry,
–dust free and
–vibration free
Repeat the conservation process after 12 months of immobilization
CAUTION
Before a new conservation process or re-installation of the vacuum
pump, make sure that the gasket, plug or adhesive tape from the
discharge connection are removed.
Commissioning after conservation
●Make sure that the gasket, plug or adhesive tape are removed
from the ports
●Commission the vacuum pump as described in the chapter “Instal-
lation and Commissioning”
Installation and
Commissioning
Installation prerequisites
CAUTION
In case of non-compliance with the installation prerequisites, parti-
cularly in case of insufficient cooling:
Risk of damage or destruction of the vacuum pump and adjoining
plant components!
Risk of injury!
The installation prerequisites must be complied with.
●Make sure that the integration of the vacuum pump is carried out
such that the essential safety requirements of the Machine Direc-
tive 98/37/EC are complied with (in the responsibility of the desi-
gner of the machinery into which the vacuum pump is to be
incorporated; see also the note in the EC-Declaration of
Conformity)
Mounting Position and space
●Make sure that the environment of the vacuum pump is not po-
tentially explosive
●Make sure that the following ambient conditions will be complied
with:
–Ambient temperature: see “Oil”
–Ambient pressure: atmospheric
●Make sure that the environmental conditions comply with the pro-
tection class of the drive motor (according to the nameplate)
●Make sure that the vacuum pump will be placed or mounted hori-
zontally
●Make sure that the base for placement / mounting base is even
●Make sure that the vacuum pump can neither inadvertently nor in-
tentionally be stepped on and cannot be used as a support for hea-
vy objects
●Make sure that the vacuum pump cannot be hit by falling objects
●Make sure that in order to warrant a sufficient cooling there will a
clearance of minimum 0,5 m between the fan hood and nearby
walls
●Make sure that no temperature sensitive parts (plastics, wood,
cardboard, paper, electronics) will touch the surface of the vacuum
pump
●Make sure that the installation space or location is vented such that
a sufficient cooling of the vacuum pump is warranted
CAUTION
During operation the surface of the vacuum pump may reach tem-
peratures of more than 70°C.
Risk of burns!
●Make sure that the vacuum pump will not be touched inadverten-
tly during operation, provide a guard if appropriate
●Make sure that the oil sight glass (i,83) will remain easily accessible
If the oil change is meant to be performed on location:
◆Make sure that the oil drain port (j,95), the oil filter (d,100)
and the oil fill port (k,88) will remain easily accessible
●Make sure that enough space will remain for the removal and the
reinsertion of the exhaust filter(s) (l,120)
Suction Connection
CAUTION
Intruding foreign objects or liquids can destroy the vacuum pump.
In case the inlet gas can contain dust or other foreign solid particles:
◆Make sure that a suitable filter (5 micron or less) is installed
upstream the vacuum pump
●Make sure that the suction line fits to the suction connection/gas
inlet (a,260) of the vacuum pump
●Make sure that the gas will be sucked through a vacuum-tight
flexible hose or a pipe
In case of using a pipe:
◆Make sure that the pipe will cause no stress on the vacuum
pump’s connection, if necessary use bellows
●Make sure that the line size of the suction line over the entire
length is at least as large as the suction connection/gas inlet
(a,260) of the vacuum pump
In case of very long suction lines it is prudent to use larger line sizes in
order to avoid a loss of efficiency. Seek advice from your Busch repre-
sentative
If two or more vacuum pumps work on the same suction line, if the
volume of the vacuum system is large enough to suck back oil or if the
vacuum shall be maintained after switching off the vacuum pump:
◆Provide a manual or automatic operated valve (= non-return
valve) in the suction line
(the non-return valve that is installed inside the suction connection is
not meant to be used for this purpose!)
If the vacuum pump is planned to be used for the suction of gas that
contains limited quantities of condensable vapour
◆Provide a shut-off valve, a drip-leg and a drain valve in the
suction line, so that condensates can be drained from the suc-
tion line
●Make sure that the suction line does not contain foreign objects,
e.g. welding scales
Discharge connection
The following guidelines for the discharge line do not apply, if the aspi-
rated air is discharged to the environment right at the vacuum pump.
Installation and Commissioning
Page 6

CAUTION
The discharged air contains small quantities of vacuum oil.
Staying in vacuum oil contaminated air bears a risk of damage to
health.
If air is discharged into rooms where persons stay, sufficient ventila-
tion must be provided for.
●Make sure that the discharge line fits to the gas discharge connec-
tion (b,153) of the vacuum pump
In case of using a pipe:
◆Make sure that the pipe will cause no stress on the discharge
connection, if necessary use bellows
●Make sure that the line size of the discharge line over the entire
length is at least as large as the gas discharge connection (b,153)
of the vacuum pump
In case of very long discharge lines it is prudent to use larger line sizes
in order to avoid a loss of efficiency and an overload of the vacuum
pump. Seek advice from your Busch representative
●Make sure that the discharge line either slopes away from the va-
cuum pump or provide a liquid separator or a drip leg with a drain
cock, so that no liquids can back up into the vacuum pump
WARNING
Discharge lines made from non-conducting material can build up
static charge.
Static discharge can cause explosion of potentially existing oil
mist.
The discharge line must be made of conducting material or provi-
sions must be made against static discharge
Electrical connection / Controls
●Make sure that the stipulations acc. to the EMC-Directive
89/336/EEC and Low-Voltage-Directive 73/23/EEC as well as the
EN-standards, electrical and occupational safety directives and the
local or national regulations, respectively, are complied with (this is
in the responsibility of the designer of the machinery into which
the vacuum pump is to be incorporated; see also the note in the
EC-Declaration of Conformity).
●Make sure that the power supply is compatible with the data on
the nameplate of the drive motor (400)
●Make sure that an overload protection according to EN 60204-1 is
provided for the drive motor
●Make sure that the drive of the vacuum pump will not be affected
by electric or electromagnetic disturbance from the mains; if neces-
sary seek advice from the Busch service
In case of mobile installation::
◆Provide the electrical connection with grommets that serve as
strain-relief
Heat exchanger (water/ oil) (accessory)
It is possible to install a heat exchanger (water/ oil) (accessory) as a
complementary cooling when we have applications with unfavourable
ambient conditions.
Connecting cooling water
The cooling water connection can be made with flexible hoses or tu-
bes.
The cooling water outlet must be without pressure.
The cooling water should match with the following requirements:
Max. cooling water pressure: 10 bar
Cooling water temperature: 15°C (max. 40°C)
Installation
Mounting
●Make sure that the “Installation Prerequisites” are complied with
●Set down or mount the vacuum pump at its location
Connecting electrically
WARNING
Risk of electrical shock, risk of damage to equipment.
Electrical installation work must only be executed by qualified per-
sonnel that knows and observes the following regulations:
- IEC 364 or CENELEC HD 384 or DIN VDE 0100, respectively,
- IEC-Report 664 or DIN VDE 0110,
- BGV A2 (VBG 4) or corresponding national accident prevention
regulation.
CAUTION
The connection schemes given below are typical. Depending on the
specific order or for certain markets deviating connection schemes
may apply.
Risk of damage to the drive motor!
The inside of the terminal box shall be checked for drive motor
connection instructions/schemes.
●Electrically connect the drive motor (400)
●Connect the protective earth conductor
Delta connection (Low voltage):
Star connection (High voltage)):
CAUTION
Operation in the wrong direction of rotation can destroy the va-
cuum pump in short time. .
Risk of explosion!
Prior to starting-up it must be made sure that the vacuum pump is
operated in the proper direction.
●Determine the intended direction of rotation with the arrow
●“Bump” the drive motor
Installation and Commissioning
Page 7
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●Watch the fan wheel of the drive motor (400) and determine the
direction of rotation just before the fan wheel stops
If the rotation of the fan wheel must be changed:
◆Switch any two of the drive motor wires in the terminal box
Connecting Lines/Pipes
In case the suction line is equipped with a shut-off valve:
◆Connect the suction line
●Connect the discharge line
Installation without discharge line:
◆Make sure that the gas discharge (b,153) is open
●Make sure that all provided covers, guards, hoods etc. are moun-
ted
●Make sure that cooling air inlets and outlets are not covered or
obstructed and that the cooling air flow is not affected adversely in
any other way
Filling Oil
In case the vacuum pump was treated with conservation oil:
◆Drain the remainders of conservation oil and top up oil (see
“Maintenance/Oil and Oil Filter Change”)
CAUTION
The vacuum pump is shipped without oil.
Operation without oil will ruin the vacuum pump in short time.
Prior to commissioning it must be made positively sure that oil is
filled in.
The vacuum pump is delivered without oil (oil specification see “Oil”).
Only oils according to DIN 51506, lubricating oil group VC must be
used. Using the correct lubricant has a determining on the end pres-
sure (the 0,1 hPa ultimate pressure is obtained with the use of VMH
100 oil type).
The application of the vacuum pump will definite the oil to be used.
CAUTION
A change of mineral oil by a synthetic oil needs a special procedure.
If the mineral oil (VM 032, VM 068, VM 100, VMH 100) has to be ex-
changed for synthetic oil (VS 100, VE 101), a specific procedure must
be applied. This procedure is available near all the Busch service
companies.
Keep approximately according to the table “Oil” ready:
–for R 5 0160 - 0202 D versions, 5 litres oil
–for R 5 0250 - 0302 D versions, 6,5 litres oil
NOTE: The amount given in these operating instructions is a guide.
The oil sight glass (i,83) indicates the actual amount to be filled in.
CAUTION
Before changing the oil type, compatibility shall be checked and, if
necessary, the pump be flushed.
CAUTION
In case the vacuum pump has potentially been treated with conser-
vation oil.
Synthetic oils (except for oils based on poly-a-olefin) are incompa-
tible with mineral oils and conservation oils.
Risk of foaming leading to destruction of the vacuum pump.
CAUTION
Filling oil through the gas inlet (a,260) will result in breakage of the
vanes (n,22) and destruction of the vacuum pump.
Oil may be filled through the oil fill port only (k,88).
CAUTION
During operation the oil separator is filled with hot, pressurised oil
mist.
Risk of injury from hot oil mist with open oil fill port.
Risk of injury if a loosely inserted oil fill plug is ejected.
Remove the oil fill plug only if the vacuum pump is stopped.
The vacuum pump must only be operated with the oil fill plug firmly
inserted.
●Remove the oil fill plug (k,88)
●Filling oil according to the values set in the table “Oil”
●Make sure that the level is between the MIN and the MAX-mar-
kings of the oil sight glass (i,83)
●Make sure that the seal ring (89) is inserted into the oil sight
glass(k,88)and undamaged, replace if necessary
●Firmly reinsert the oil sight glass (k,88) together with the seal ring
(89)
NOTE: Starting the vacuum pump with cold oil is made easier when at
this very moment the suction line is neither closed nor covered with a
rubber mat.
●Switch on the vacuum pump
In case the suction line is equipped with a shut-off valve:
◆Close the shut-off valve
In case the suction line is not equipped with a shut-off valve:
◆Cover the suction connection with a piece of rubber mat
(a,260)
●Let the vacuum pump run for a few minutes
●Shut down the vacuum pump and wait a few minutes
●Make sure that the level is between the MIN and the MAX-mar-
kings of the oil sight glass (i,83)
In case the level has fallen below the MIN-marking of the oil sight
glass:
◆Top-up oil
In case the suction line is equipped with a shut-off valve:
◆Open the shut-off valve
In case the suction line is not equipped with a shut-off valve:
◆Remove the suction connection with a piece of rubber mat
Recording of Operational Parameters
As soon as the vacuum pump is operated under normal operating
conditions:
●Measure the drive motor current and record it as reference for fu-
ture maintenance and troubleshooting work
Version with exhaust filter pressure gauge
◆Read the scale of the exhaust filter pressure gauge and record
it as reference for future maintenance and troubleshooting
work
Installation and Commissioning
Page 8

Operation Notes
Application
CAUTION
The vacuum pump is designed for operation under the conditions
described below.
In case of disregard risk of damage or destruction of the vacuum
pump!
Risk of Injury!
The vacuum pump must be operated under the conditions described
below.
The vacuum pump is designed for
–the suction
of
–air and other dry, non-aggressive, non-toxic and non-explosive ga-
ses
Conveying media with a higher density than air leads to an increased
thermal and mechanical load on the vacuum pump and is permissible
only after prior consultation with Busch
Max. allowed temperature of the inlet gas:
See “Oil, Ambient temperature range”
In case the vacuum pump is equipped with a gas ballast (optional) wa-
ter vapour within the gas flow can be tolerated within certain limits
(see “Installation and Commissioning, Operating Notes, Conveying
Condensable Vapours”). The conveyance of other vapours shall be
agreed upon with Busch.
The vacuum pump is made for the intended use in potentially explosive
areas
The vacuum pump is thermally suitable for continuous operation.
The vacuum pump is ultimate pressure proof.
CAUTION
During operation the surface of the vacuum pump may reach tem-
peratures of more than 70 °C.
Risk of burns!
The vacuum pump shall be protected against contact during
operation.
CAUTION
The discharged air contains small quantities of vacuum oil.
Staying in vacuum oil contaminated air bears a risk of damage to
health.
If air is discharged into rooms where persons stay, sufficient ventila-
tion must be provided for.
CAUTION
The vacuum pump emits noise of high intensity.
Risk of damage to the hearing.
Persons staying in the vicinity of a non noise insulated vacuum
pump over extended periods shall wear ear protection.
●Make sure that all provided covers, guards, hoods etc. are moun-
ted
●Make sure that protective devices will not be disabled.
●Make sure that cooling air inlets and outlets are not covered or
obstructed and that the cooling air flow is not affected adversely in
any other way
●Make sure that the “Installation Prerequisites” (see “Installation
Prerequisites and Commissioning” are complied with and will re-
main complied with, particularly that a sufficient cooling will be
ensured.
Conveying Condensable Steams
CAUTION
Residual condensates dilute the oil, deteriorate its lubricating proper-
ties and can cause a jam of the rotor.
Apply a suitable operating method to make sure that no condensa-
tes remain in the vacuum pump.
In order to use the vacuum pump for the conveyance of
condensable vapours, the vacuum pump must be equipped with
shut-off valve in the suction line and with a gas ballast valve.
The quantity of condensable steams are indicated in the table “Techni-
cal Data”.
Version with gas ballast device with ball-cock:
◆Make sure that the ballast valve (477) is open and will remain
open during operation
Version with gas ballast device with solenoid valve:
◆Make sure that the solenoid valve is closed
NOTE: In the case of an operation with a gas ballast device with a
solenoid valve, this one opens at the start of the vacuum pump in
star connection, this in order to discharge the motor. With the exis-
ting connection between the oil separator and the inlet flange, the
air flow is assured.
The solenoid valve is closed when the motor passes in phase delta
and the vacuum can thus be obtained.
●Close the shut-off valve in the suction line
●Operate the vacuum pump with the shut-off valve in the suction
line closed for approx. half an hour, so that the operating tempera-
ture will rise to approx. 75°C
At process start:
●Open the shut-off valve in the suction line
At process end:
●Close the shut-off valve in the suction line
●Operate the vacuum pump for another approx. half an hour
Maintenance
WARNING
In case the vacuum pump conveyed gas that was contaminated
with foreign materials which are dangerous to health, harmful ma-
terial can reside in filters.
Danger to health during inspection, cleaning or replacement of fil-
ters.
Danger to the environment.
Personal protective equipment must be worn during the handling
of contaminated filters.
Contaminated filters are special waste and must be disposed of se-
parately in compliance with applicable regulations
Maintenance
Page 9

CAUTION
During operation the surface of the vacuum pump may reach tem-
peratures of more than 70°C.
Risk of burns!
●Prior to action that requires touching of the vacuum pump, let the
vacuum pump cool down.
In case of oil draining:
◆Let the vacuum pump cool down for no more than 20 minutes
●Prior to disconnecting connections make sure that the connected
pipes/lines are vented to atmospheric pressure
Maintenance Schedule
NOTE: The maintenance intervals depend very much on the individual
operating conditions. The intervals given below shall be considered as
starting values which should be shortened or extended as appropriate.
Particularly heavy duty operation, such like high dust loads in the envi-
ronment or in the process gas, other contaminations or ingress of pro-
cess material, can make it necessary to shorten the maintenance
intervals significantly.
Monthly:
●Make sure that the vacuum pump is shut down and locked against
inadvertent start up
●Check the level and the colour of the oil (see “Checking the Oil”)
●Check the vacuum pump for oil leaks - in case of leaks have the
vacuum pump repaired (Busch service)
●Check the function of the exhaust filters (l,120) (see “Exhaust Fil-
ters”)
In case an inlet air filter is installed:
◆Check the inlet air filter, if necessary clean (with compressed
air) or replace
In case of operation in a dusty environment:
◆Make sure that the housing is free from dust and dirt, clean if
necessary (see “Every 6 Months:”)
Every 6 Months:
●Make sure that the vacuum pump is shut down and locked against
inadvertent start up
●Make sure that the housing is free from dust and dirt, clean if ne-
cessary
●Clean the fan cowlings, fan wheels, ventilation protection screen
and coolingfins
Yearly:
●Make sure that the vacuum pump is shut down and locked against
inadvertent start up
●Replace the exhaust filters (l,120) (see “Exhaust filters”)
In case an inlet filter is installed:
◆Clean (with compressed air) or replace the inlet air filter
●Check the inlet screen (h, 261), clean if necessary
Every 500 - 2000 Operating hours (see “Oil Life”)
●Change the oil, replace the oil filter(s) (d,100) and clean the level
switch (m,194) (see “Oil and Oil Filter Change”)
Every 16000 Operating hours, at the latest after 4
Years:
●Have a major overhaul on the vacuum pump (Busch service)
Checking the oil
Checking the level
●Make sure that the vacuum pump is shut down and locked against
inadvertent start up
●Make sure that the oil has collected at the bottom of the oil sepa-
rator (f,75)
●Read the level on the sight glass (i,83)
In case the level has dropped underneath the MIN-marking:
◆Top up oil (see “Topping up Oil”)
In case the level exceeds the MAX-marking:
◆Check the dilution with condensates.
◆Change the oil (see “Change the oil”)
If appropriate retrofit a gas ballast (Busch Service) and observe the
chapter “Operating Notes, Conveying Condensable Vapours”
Topping up Oil
NOTE: Under normal conditions there should be no need to top up oil
during the recommended oil change intervals. A significant level drop
indicates a malfunction (see “Troubleshooting”).
NOTE: During operation the exhaust filter gets saturated with oil. It is
therefore normal that the oil level will drop slightly after replacement of
the exhaust filter.
CAUTION
Filling oil through the suction connection/gas inlet (a,260) will result
in breakage of the vanes (n,22) and destruction of the vacuum
pump.
Oil may be filled through the oil fill port only (k,88).
CAUTION
During operation the oil separator is filled with hot, pressurised oil
mist.
Risk of injury from hot oil mist with open oil inlet plug (k,88).
Remove the oil inlet port (k,88) only the vacuum pump is stopped.
The vacuum pump must only be operated with the oil inlet plug
(k,88) firmly inserted.
●Make sure that the vacuum pump is shut down and locked against
inadvertent start up
●Remove the oil inlet port (k,88)
●Top up oil until the level reaches the middle of the oil sight glass
(i,83)
●Make sure that the level is between the MIN and the MAX-mar-
kings of the oil sight glass (i,83)
●Make sure that the sealing seat (89) on the oil fill plug (k,88) is un-
damaged, if necessary replace the oil fill plug
●Firmly reinsert the oil fill plug (k,89) with its sealing seat (89)
Checking the Colour of the Oil
NOTE: The oil should be light, either transparent, a little foamy or a
little tarnished. A milky discolouration that does not vanish after seda-
tion of the oil indicates contamination with foreign material. Oil that is
either contaminated with foreign material or burnt must be changed
(see “Oil Change”).
Oil Life
The oil life depends very much on the operating conditions. A clean
and dry air stream and operating temperatures below 100°C are ideal.
Maintenance
Page 10

Under these conditions the oil and the oil filter shall be changed every
5000 operating hours or after half a year.
Under very unfavourable operating conditions the oil life can be less
than 500 operating hours. Extremely short life times indicate malfunc-
tions (see “Troubleshooting”) or unsuitable operating conditions,
though
If there is no experience available with regard to the oil life under the
prevailing operation conditions, it is recommended to have an oil ana-
lysis carried out every 500 operating hours and establish the change in-
terval accordingly.
Oil and Oil Filter Change
WARNING
In case the vacuum pump conveyed gas that was contaminated
with harmful foreign material the oil will be contaminated with
harmful material.
Danger to health during the changing of contaminated oil.
Danger to the environment.
Personal protective equipment must be worn during the changing
of contaminated oil.
Contaminated oil is special waste and must be disposed of separa-
tely in compliance with applicable regulations.
Draining Used Oil
NOTE: After switching off the vacuum pump at normal operating tem-
perature wait no more than 20 minutes before the oil is drained.
●Make sure that the vacuum pump is shut down and locked against
inadvertent start up
●Make sure that the vacuum pump is vented to atmospheric pres-
sure
●Put a drain tray underneath the oil drain port (j,95)
●Remove the oil drain plug (j,95)
●Drain the oil
When the oil stream dwindles:
●Close the oil drain plug (j,95)
●Switch the vacuum pump on for a few seconds
●Make sure that the vacuum pump is shut down and locked against
inadvertent start up
●Remove the oil drain plug
●Make sure that the sealing seat on the oil drain plug is undama-
ged, if necessary replace the oil drain plug
●Firmly reinsert the oil drain plug
●Dispose of the used oil in compliance with applicable regulations
Flushing the vacuum pump
WARNING
Degraded oil can choke pipes and coolers.
Risk of damage to the vacuum pump due to insufficient lubrication.
Risk of explosion due to overheating.
If there is a suspicion that deposits have gathered inside the va-
cuum pump the vacuum pump shall be flushed.
●Make sure that all the used oil is drained
●= Make sure that the used oil filter (d,100) is still in place
●Create respectively 5 litres of flushing agent for the versions R 5
0160 - 0202 D and 6,5 litres of flushing agent for the versions R 5
0250 - 0302 D from 50 percent oil and 50 percent paraffin or die-
sel fuel/fuel oil
●Make sure that the oil drain plug (j,95) is reinsert correctly
●Remove the oil fill plug (k,88)
●Fill in the flushing agent
●Firmly reinsert the oil fill plug (k,88) with its sealing seat (89)
●Close the suction line
●Run the vacuum pump for at least half an hour
●Drain the flushing agent and dispose of it in compliance with appli-
cable regulations
NOTE: Due to the use of paraffin and even more in case of using Die-
sel fuel/fuel oil, unpleasant odour can occur after recommissioning. If
this is a problem, Diesel fuel/fuel oil should be avoided and the va-
cuum pump be run at idle in a suitable place until the unpleasant odour
vanishes.
Cleaning of the level switch
●Make sure that all the entire used oil is drained
●Unscrew the fixing screws (142) of exhaust cover plate, take off
the washers (143) and remove the exhaust cover plate (140)
●Check the seal (141) and replace if necessary
●Unscrew the fixing screws (196) and remove the float (194)
●Check the o-ring (197) and replace if necessary
●Check float for cleanliness and good operation. Bast clean with
compressed air if necessary
●For reassembly, please refit float to its support (195) whilst taking
care to fit it the correct way round
Replacing the Oil Filter
●Make sure that the entire used oil is drained
●Remove the oil filter (d,100)
●Apply a drop of fresh oil on the seal ring of the new oil filter
(d,100)
●Mount the new oil filter (d,100) and tighten it by hand
Filling in Fresh Oil
●Keep oil acc. to the table “Oil” ready
NOTE: The amount given in these operating instructions is a guide.
The oil sight glass (i,83) indicates the actual amount to be filled in.
●Make sure that the oil outlet plug (j,95) is firmly inserted
CAUTION
Filling oil through the suction connection/gas inlet (a,260) will result
in breakage of the vanes (n,22) and destruction of the vacuum
pump.
Oil may be filled through the oil fill port only (k,88).
●Remove the oil fill plug (k,88)
●Fill in oil
●Make sure that the level is between the MIN and the MAX-mar-
kings of the oil sight glass (i,83)
●Make sure that the seal ring (89) is inserted into the oil inlet plug
(k,88) and undamaged, replace if necessary
●Firmly reinsert the oil inlet plug (k,88) together with the seal ring
(89)
Exhaust Filter
Check during operation
Busch recommends the use of a filter pressure gauge (available as ac-
cessory, see “Accessories”). Without filter pressure gauge the filter re-
Maintenance
Page 11

sistance shall be assessed on the basis of the drive motor current
drawn.
●Make sure that the vacuum pump is running
Version with filter pressure gauge:
◆Check that the indication of the filter pressure gauge is in the
usual range (< 0,6 bar)
Version without filter pressure gauge:
◆Check that the drive motor current drawn is in the usual range
(see nameplate)
●Check that the discharge air is free from oil
NOTE: The discharge air will also contain oil if the vacuum pump is
operated without interruption for too long a period (see “Operation
Notes”).
Assessment
If
the indication of the filter pressure gauge is in the red field, (> 0,6 bar)
or
the drive motor (400) draws too much current and/or the pump flow
rate has dropped,
then the exhaust filters (l,120) are clogged and must be replaced.
NOTE: Exhaust filters cannot be cleaned successfully. Clogged exhaust
filters must be replaced with new ones.
If
the filter pressure gauge indicates a lower pressure than usual,
or
the drive motor draws less current than usual,
the exhaust filters (l,120) can be clogged and must be replaced.
If the discharge air contains oil,
the exhaust filters (l, 120) can be clogged or broken through and, if ap-
plicable, must be replaced.
Change of the exhaust filters
WARNING
In case the vacuum pump conveyed gas that was contaminated
with foreign materials which are dangerous to health, harmful ma-
terial can reside in filters.
Danger to health during inspection, cleaning or replacement of fil-
ters.
Danger to the environment.
Personal protective equipment must be worn during the handling
of contaminated filters.
Contaminated filters are special waste and must be disposed of se-
parately in compliance with applicable regulations.
Removing the exhaust filters
●Make sure that the vacuum pump is shut down and locked against
inadvertent start up
●Prior to disconnecting pipes/lines make sure that the connected pi-
pes/lines are vented to atmospheric pressure
●Remove the discharge line, if necessary
●Remove the discharge cover (142) from the oil separator
●Remove the seal for the separator cover (141), if necessary
●Release the spring elements (125) by unscrewing the screws (126)
and remove them
●Remove the exhaust filters (l,120) and the o-rings (121)
In the case of a R 5 0160 D or R 5 0202 D version:
◆The exhaust filters are two
In the case of a R 5 0250 D or R 5 0302 D version:
◆The exhaust filters are three
Inserting the Exhaust Filters
CAUTION
The non-OEM spares market offers exhaust filters that are geome-
trically compatible with Busch-vacuum pumps, but do not feature
the high retention capacity of genuine Busch-exhaust filters and de-
teriorate the service life and the efficiency of the vacuum pump due
to their increased back pressure.
Increased risk of damage to health.
Adverse effect on efficiency and service life.
In order to keep the emission on the lowest possible level and to
preserve efficiency and service life only genuine Busch-exhaust
filters shall be used.
●Insert the new exhaust filters with the new o-rings into the oil se-
parator (75). Be sure to fit the exhaust filters as indicated by the ar-
row at exhaust filters
●Mount spring elements (125) and apply a tension to the spring ele-
ments by means of the screw of tension (126)
●Check the cover seal (141) and replace it if necessary
●Mount the discharge cover
NOTE: During operation the exhaust filters get saturated with oil. It is
therefore normal that the oil level will drop slightly after replacement of
the exhaust filters.
Gas ballast
Check the gas ballast inlet regularly. If the gas ballast doesn’t work cor-
rectly, disassemble it, clean it and blow it with compressed air.
Inlet flange
Check the inlet flange regularly. The maintenance interval of the inlet
flange depends on the application.
To clean the mesh screen (h,261) at the inlet:
–Remove the upper parts of the inlet flange
–Remove the flange
–Remove the mesh screen (h,261) and clean it with compressed air
–Check the different seals and replace them if necessary
–Mount the mesh screen and the inlet flange
Fan cover
Check the fan cover regularly. A bad maintenance of the fan cover will
affect the vacuum pump cooling and may lead to overheating of the
vacuum pump.
Motor cover
Check the motor cover regularly. A bad maintenance of the motor co-
ver will affect the vacuum pump cooling and may lead to overheating
of the vacuum pump.
Maintenance
Page 12

Overhaul
CAUTION
In order to achieve best efficiency and a long life the vacuum pump
was assembled and adjusted with precisely defined tolerances.
This adjustment will be lost during dismantling of the vacuum
pump.
It is therefore strictly recommended that any dismantling of the va-
cuum pump that is beyond of what is described in this manual shall
be done by the Busch service.
CAUTION
Improper work on the vacuum pump put the operating safety at
risk.
Risk of explosion!
Approval for operation will be void!
Any dismantling of the vacuum pump that is beyond of what is des-
cribed in this manual must be done by specially trained Busch ser-
vice personnel only.
WARNING
In case the vacuum pump conveyed gas that was contaminated
with foreign materials which are dangerous to health, harmful ma-
terial can reside in oil and condensates.
Danger to health during dismantling of the vacuum pump.
Danger to the environment.
Prior to shipping the vacuum pump shall be decontaminated as
good as possible and the contamination status shall be stated in a
“Declaration of Contamination” (form downloadable from
www.busch-vacuum.com).
Busch service will only accept vacuum pumps that come with a com-
pletely filled in and legally binding signed “Declaration of Contamina-
tion” (form downloadable from www.busch-vacuum.com).
Removal from Service
Temporary Removal from Service
●Prior to disconnecting pipes/lines make sure that all pipes/lines are
vented to atmospheric pressure
Recommissioning
CAUTION
Vanes (n,22) can stick after a long period of standstill.
Risk of vane breakage if the vacuum pump is started with the drive
motor.
After longer periods of standstill the vacuum pump shall be turned
by hand.
After longer periods of standstill:
◆Make sure that the vacuum pump is shut down and locked
against inadvertent start up
◆Remove the cover around the fan of the drive motor
◆Slowly rotate the fan wheel by hand several revolutions in the
intended direction of rotation (see stuck on or cast arrow
◆Mount the cover around the fan wheel of the drive motor
If deposits could have gathered in the vacuum pump:
◆Flush the vacuum pump (see “Maintenance”)
●Observe the chapter “Installation and Commissioning”
Dismantling and Disposal
WARNING
In case the vacuum pump conveyed gas that was contaminated
with harmful foreign material the operating fluid and the exhaust
filter(s) will be contaminated with harmful material.
Harmful material can reside in pores, gaps and internal spaces of
the vacuum pump.
Danger to health during dismantling of the vacuum pump.
Danger to the environment.
During dismantling of the vacuum pump personal protective equip-
ment must be worn.
The vacuum pump must be decontaminated prior to disposal.
Prior to shipping the vacuum pump shall be decontaminated as
good as possible and the contamination status shall be stated in a
“Declaration of Contamination” (form downloadable from
www.busch-vacuum.com).
Operating fluid and exhaust filters must be disposed of separately
in compliance with applicable regulations.
CAUTION
Used oil, used exhaust filters and used oil filters are special waste
and must be disposed of in compliance with applicable regulations.
●Remove the exhaust filter (l,120) (see “Maintenance, Exhaust Fil-
ter”)
●Drain the oil
●Remove the oil filter (d,100)
●Make sure that materials and components to be treated as special
waste have been separated from the vacuum pump
●Make sure that the vacuum pump is not contaminated with harm-
ful foreign material
According to the best knowledge at the time of printing of this manual
the materials used for the manufacture of the vacuum pump involve no
risk.
●Dispose of the used oil in compliance with applicable regulations
●Dispose of special waste in compliance with applicable regulations
●Dispose of the vacuum pump as scrap metal
Overhaul
Page 13

Troubleshooting
WARNING
Risk of electrical shock, risk of damage to equipment.
Electrical installation work must only be executed by qualified personnel that knows and observes the following regulations:
- IEC 364 or CENELEC HD 384 or DIN VDE 0100, respectively,
- IEC-Report 664 or DIN VDE 0110,
- BGV A2 (VBG 4) or equivalent national accident prevention regulation.
CAUTION
During operation the surface of the vacuum pump may reach temperatures of more than 70°C.
Risk of burns!!
Let the vacuum pump cool down prior to a required contact or wear heat protection gloves.
Problem Possible Cause Remedy
The vacuum pump does not reach the usual
pressure
The vacuum system or suction line is not
leak-tight
Check the hose or pipe connections for pos-
sible leak
The drive motor draws a too high current
(compare with initial value after commissio-
ning))
Contaminated oil (the most common cause) Drain the oil
(see “Maintenance”)
Evacuation of the system takes too long No or not enough oil in the reservoir Top up oil
(see “Maintenance”)
The exhaust filters (l) are partly clogged Replace the exhaust filters (l)
(see “Maintenance”)
The oil filter is partly clogged
(the oil flows through the bypass only, the oil
does not get filtered any more)
Replace the oil filter (d)
(see “Maintenance”)
In case a mesh screen (h) is installed on the
suction connection (a):
The mesh screen (h) on the suction connec-
tion (a) is partly clogged
Clean the mesh screen (h)
If cleaning is required too frequently install a
filter upstream
In case an inlet filter is installed on the suction
connection (a):
The filter on the suction connection (a) is
partly clogged
Clean or replace the inlet filter, respectively
Partial clogging in the suction, discharge or
pressure line
Remove the clogging
Long suction, discharge or pressure line with
too small diameter
Use larger diameter
The valve disk (251) of the inlet non-return
valve is stuck in closed or partially open posi-
tion
Disassemble the inlet, clean the mesh screen
(h) and the valve (251-254) as required and
reassemble
The oil tubing is defective or leaking
The oil return line is broken
Tighten the connections
Replace the connections and/or the tubing
(replace with identically dimensioned parts
only)
A shaft seal is leaking Replace the shaft seal ring (Busch service)
The exhaust valve (g) is not properly seated or
stuck in partially open position
Disassemble and reassemble the exhaust
valve(s) (g) (Busch service)
A vane(n) is blocked in the rotor or otherwise
damaged
Free the vanes (n) or replace with new ones
(Busch service)
Troubleshooting
Page 14

The radial clearance between the rotor (o) and
the cylinder is no longer adequate
Readjust the vacuum pump (Busch service)
Internal parts worn or damaged Repair the vacuum pump (Busch service)
The oil return line starts in an area vented to atmospheric pressure. Particularly on small model
pumps, a fairly large amount of air is sucked through the oil return line, which may prevent the
ultimate pressure from reaching 20 bar abs.
In order to exclude this possible cause:
squirt oil through the gas discharge/pressure connection (b) into the oil return line. While oil is
being sucked in, the ultimate pressure is not affected by the air normally sucked through the oil
return line.
The gas conveyed by the vacuum pump
smells displeasing
Process components evaporating under va-
cuum
Readily volatile and thus gaseous components
of the oil, e.g. additives, particularly right after
an oil change.
NOTE: This is no indication of a malfunction
of the oil separator. The oil separator is able
to retain droplets of oil, however no gaseous
components of it
Check the process, if applicable
Use a different type of oil, if applicable
The vacuum pump does not start The drive motor is not supplied with the cor-
rect voltage or is overloaded
Supply the drive motor with the correct vol-
tage
The drive motor starter overload protection is
too small or trip level is too low
Compare the trip level of the drive motor star-
ter overload protection with the data on the
nameplate
Correct if necessary
In case of high ambient temperature:
Set the trip level of the drive motor starter
overload protection 5 percent above the no-
minal drive motor current
One of the fuses has blown Check the fuses
The connection cable is too small or too long
causing a voltage drop at the vacuum pump
Use sufficiently dimensioned cable
The vacuum pump or the drive motor is bloc-
ked
Make sure the drive motor is disconnected
from the power supply
Remove the fan cover
Try to turn the fan by hand
If the unit vacuum pump/drive motor is still
frozen:
Remove the drive motor and check the drive
motor and the vacuum pump separately
If the vacuum pump is blocked:
Repair the vacuum pump (Busch service)
The drive motor is defective Replace the drive motor (Busch service)
The vacuum pump is blocked Solid foreign matter has entered the vacuum
pump
Repair the vacuum pump (Busch service)
Make sure the suction line is equipped with a
mesh screen
If necessary additionally provide a filter
Corrosion in the vacuum pump from remai-
ning condensate
Repair the vacuum pump (Busch service)
Check the process
Observe the chapter “Installation and Com-
missioning, Operating Notes, Conveying Con-
densable Vapours”
The vacuum pump was run in the wrong di-
rection
Repair the vacuum pump (Busch service)
When connecting the vacuum pump make
sure the vacuum pump will run in the correct
direction (see “Installation”)
Troubleshooting
Page 15

After shutting down the vacuum pump the
vacuum system exerted underpressure onto
the pump chamber which sucked back exces-
sive oil from the oil separator into the pump
chamber
When the vacuum pump was restarted too
much oil was enclosed between the vanes (n)
Oil could not be compressed and thus broke a
vane (n)
Repair the vacuum pump (Busch service)
Make sure the vacuum system will not exert
underpressure onto the shut-down vacuum
pump, if necessary provide an additional
shut-off valve or non-return valve
Condensate ran into the pump chamber
When the vacuum pump was restarted too
much condensate was enclosed between the
vanes (n)
Condensate could not be compressed and
thus broke a vane (n)
Repair the vacuum pump (Busch service)
Make sure no condensate will enter the va-
cuum pump, if necessary provide a drip leg
and a drain cock
Drain condensate regularly
The drive motor is running, but the vacuum
pump stands still
The coupling between the drive motor and
the vacuum pumpis defective
Replace the coupling
The vacuum pump starts, but labours or runs
noisily or rattles
The drive motor draws a too high current
(compare with initial value after commissio-
ning)
Connection(s) in the drive motor terminal box
are defective
Not all drive motor coils are properly connec-
ted
The drive motor operates on two phases only
Check the proper connection of the wires
against the connection diagram
Tighten or replace loose connections
The vacuum pump runs in the wrong direc-
tion
Verification and rectification see “Installation
and Commissioning”, correct if necessary
Standstill over several weeks or months Let the vacuum pump run warm with inlet
closed
Oil viscosity is too high for the ambient tem-
perature
Use synthetic oil, if necessary use oil of the
next lower viscosity class (CAUTION: opera-
tion with too low viscosity can cause chatter
marks inside the cylinder)
Warm up the oil with a heating prior to star-
ting up the vacuum pump or, make sure that
the vacuum pump runs in intervals in order
not to let it get too cold.
Improper oil quantity, unsuitable oil type Use the proper quantity of one of the recom-
mended oils
(see “Oil”,
Oil change see “Maintenance”)
No oil change over extended period of time Perform oil change incl. Flushing (see “Main-
tenance”)
The exhaust filters (l) are clogged and appear
black from burnt oil
Flush the vacuum pump
Replace the oil filter (d)
Replace the exhaust filter (l)
Fill in new oil
(see “Maintenance”)
In case the oil life is too short: use oil with
better heat resistance (see “Oil”) or retrofit
cooling
Foreign objects in the vacuum pump
Broken vanes (n)
Stuck bearings
Repair the vacuum pump (Busch service)
The vacuum pump runs very noisily Defective bearings Repair the vacuum pump (Busch service)
Worn coupling elemen Replace the coupling element
Stucked vanes (n) Repair the vacuum pump (Busch service)
Use only approved oils (see “Oil”) and
change more frequently
Troubleshooting
Page 16

The vacuum pump runs very hot
(the oil sump temperature shall not exceed
100 °C)
Insufficient air ventilation Make sure that the cooling of the vacuum
pump is not impeded by dust/dirt
Clean the fan cowlings, fan wheels, ventila-
tion screens and cooling fins
Install the vacuum pump in a narrow space
only if sufficient ventilation is ensured
On a vacuum pump with oil-cooler:
Clean the intermediate spaces of the finned
tube
Ambient temperature too high Observe the permitted ambient temperatures
Temperature of the inlet gas too high Observe the permitted temperatures for the
inlet gas
The exhaust filter(l) is partially clogged Replace the exhaust filters (l)
The oil filter is partially clogged
(the oil flows through the bypass only, the oil
does not get filtered any more)
Replace the oil filter (d)
(see “Maintenance”)
Not enough oil in the reservoir Top up oil
Oil burnt from overheating Flush the vacuum pump
Replace the oil filter (d)
Replace the exhaust filters (l)
Fill in new oil
(see “Maintenance”)
In case the oil life is too short: use oil with
better heat resistance (see “Oil”) or retrofit
cooling
Mains frequency or voltage outside tolerance
range
Provide a more stable power supply
In case a mesh screen (h) is installed on the
suction connection (a):
The mesh screen (h) on the suction connec-
tion (a) is partially clogged
Clean the mesh screen (h)
If cleaning is required too frequently install a
filter upstream
In case an inlet air filter is installed on the suc-
tion connection (a):
The filter on the suction connection (a) is
partially clogged
Clean or replace the filter
Partial clogging in the suction or discharge
line
Remove the clogging
Long suction, discharge or pressure line with-
too small diameter
Use larger diameter
The vacuum pump fumes at the exhaust side
or expels oil droplets through the outlet
The oil level drops
The exhaust filters (l) are not properly seated Check the proper position of the exhaust fil-
ters
(see “Maintenance”)
The O-rings from the exhaust filters are mis-
sing or damaged
Add or replace the O-rings
(see “Maintenance”)
The exhaust filters (1) show cracks Replace the exhaust filters (l)
(see “Maintenance”)
The exhaust filters (1) are clogged with fo-
reign matter
NOTE: The saturation of the exhaust filters-
with oil is no fault and does not impair the
function of the exhaust filters! Oil dropping
down from the exhaust filters is returned to
the oil circulation.
Replace the exhaust filters (l)
(see “Maintenance”)
Troubleshooting
Page 17

The oil return valve is clogged Clean the oil return valve
(see “Maintenance, Oil change/Oil Filter, Oil
Return Valve cleaning”)
The oil return line is clogged or broken Repair the oil tubing (Busch service)
Replace a broken oil return line with an identi-
cally dimensioned line
Fill in new oil
The oil is black Oil change intervals are too long
The oil was overheated
Flush the vacuum pump
Replace the oil filter(d)
Replace the exhaust filters (l)
Fill in new oil
(see “Maintenance”)
In case the oil life is too short: use oil with
better heat resistance (see “Oil”) or retrofit
cooling
The oil is watery and coloured white The vacuum pump aspirated water or signifi-
cant amounts of humidity
Flush the vacuum pump
Replace the oil filter(d)
Replace the exhaust filters (l)
Flush the vacuum pump
(see “Maintenance”)
Modify the operational mode
(see “Installation and Commissioning, Opera-
ting Notes, Conveying Condensable
Vapours”)
The oil is resinous and/or sticky Improper oil type, perhaps in confusion Flush the vacuum pump
Replace the oil filter(d)
Replace the exhaust filters (l)
Fill in new oil
(see “Maintenance”)
Make sure the proper oil is used for the appli-
cation
The oil foams Mixing of incompatible oils Flush the vacuum pump
Replace the oil filter(d)
Replace the exhaust filters (l)
Fill in new oil
(see “Maintenance”)
Make sure the proper oil is used for the appli-
cation
Troubleshooting
Page 18

Exploded view
Exploded view
Page 19

Spare parts
NOTE: When ordering spare parts or accessories acc. to the table be-
low please always quote the type and the serial no. of the vacuum
pump. This will allow Busch service to check if the vacuum pump is
compatible with a modified or improved part.
This parts list applies to a typical configuration of the standard vacuum
pump. Depending on the specific order deviating parts data may apply.
Pos. Part Qt R 5 0160 D
R 5 0202 D
18 Sleeve 20472 000 008
22 Vanes 30722 516 573
30 Needle bearing 20473 507 139
35 Shaft seal 40487 000 012
49 O-ring 2 0486 000 587
50 O-ring 2 0486 000 543
60 Taper pin 4 0437 502 718
61 Parallel pin 40437 534 364
84 Seal 10480 000 231
88 Plug 1 0710 000 002
89 Seal 10482 000 021
89 O-ring 1 0486 000 513
95 Drain plug 1 0710 000 010
96 O-ring 1 0486 000 505
100 Oil filter 10531 000 001
106 Oil separator seal 10481 503 784
120 Exhaust filter 20532 000 508
121 O-ring 2 0486 000 512
141 Seal 10481 503 786
159 Discharge valve 20916 529 297
162 Seal 10481 503 785
185 Oil separator seal 10481 516 780
197 O-ring 1 0486 516 620
206 Oil separator seal 10481 502 719
242 O-ring 2 0486 000 587
253 O-ring 1 0486 000 526
255 O-ring 2 0486 000 531
261 Mesh screen 10534 000 041
Pos. Part Qt R 5 0250 D
R 5 0302 D
18 Sleeve 20472 000 008
22 Vanes 30722 516 729
30 Needle bearing 20473 507 139
35 Shaft seal 40487 000 012
49 O-ring 2 0486 000 587
50 O-ring 2 0486 000 543
60 Taper pin 4 0437 502 718
61 Parallel pin 40437 534 364
84 Seal 10480 000 231
88 Plug 1 0710 000 002
89 Seal 10482 000 021
89 O-ring 1 0486 000 513
95 Drain plug 1 0710 000 010
96 O-ring 1 0486 000 505
100 Oil filter 10531 000 001
106 Oil separator seal 10481 502 719
120 Exhaust filter 20532 000 508
121 O-ring 2 0486 000 512
141 Seal 10481 502 721
159 Discharge valve 20916 529 297
162 Seal 10481 502 720
185 Oil separator seal 10481 516 781
197 O-ring 1 0486 516 620
206 Oil separator seal 10481 502 719
242 O-ring 2 0486 000 587
253 O-ring 1 0486 000 526
255 O-ring 2 0486 000 531
261 Mesh screen 10534 000 041
Spare parts
Page 20