Anest Iwata EPM Series User manual

This manual contains IMPORTANT
WARNINGS, CAUTIONS and other
instructions. Read and understand the
instructions manual carefully before use
and retains it for reference
MODEL
SERIAL NO.
DISTRIBUTOR
PURCHASE DATE
OPERATION COMMENCED
EPM Series Air Compressor
Installation, Instruction and
Maintenance Manual

Preface
——
Editor
This manual describes the safety precautions, structure and functions of all systems and
components , as well as the operation and maintenance methods for the Anest Iwata Motherson
series screw air compressors designed by Anest Iwata Motherson Company.
The operators shall read this manual carefully. Only after thorough understanding the structure and
functions of all systems and components as well as the safety precautions, can they start operating
and maintaining the unit. In addition to the descriptions in the manual, if the user fails to follow the
operation and maintenance procedures in the manual for the operation and maintenance, or
dismantles and modifies the machine by itself, or uses the parts not specified by Anest Iwata
Motherson Company, the user shall loss the right for claims.
There is no catalogue for the illustrations of parts and components given in the manual. If you want
to order the parts from our company, please consult the part manual for related units. It is noted that
Anest Iwata Motherson Company is continuously researching and improving its products and the
contents of part manual may vary from the actual products after a certain period. Before you order
the parts, please confirm it with the service (parts) department of our company in advance.
This manual gives a general description of the motor, electrical system and maintenance. However,
if you have any questions before operating and maintaining the unit, please contact the local dealer
or the service department of Anest Iwata Motherson Company
October,
2018

Safety Warning Signs
In this manual, the operations and items related to safety are identified for their risks, and they are
classified based on the severity of machine damages and the level of injuries caused due to the
operations. They are represented and described in boldface with the following signs respectively.
“Caution” is meant to the unsafe factors which may cause general damage to the machines or
injuries.
“Warning” is meant to the unsafe factors which may cause property loss or the injuries.
“Danger” is meant to the unsafe factors which will cause the severe accidents or injuries.
“Danger” is meant to the unsafe factor which has the voltage exceeding the safety level to cause
severe injuries. All electrical operations shall be performed by the qualified electricians.
“Caution” is meant to the unsafe factor which has the hot surface to cause the property loss or the
injuries.
“Caution” is meant to the important installation, operation and maintenance information.

Safety Tips
Please read the following information carefully before operating and
using the compressors
Warning
The risks are present in the compressed air and compressed air system!
If you fail to follow the operating procedures and safety precautions in the operation manual,
there
maybe accidents and injuries to yourself or other persons!
Before operating and maintaining the compressors, you must read carefully and understand
the
operating manual!
The detailed instructions are given to the safety precautions which shall be followed for
operating the machines and the places with risks in the Chapter ”Safety Rules”. Before
delivering the machines, the clear warning appliques have been attached to the places with risks
and the places requiring careful operations.
1. Before any operations and maintenance on the unit, you must read and understand the
operation
manual.
2. It is never allowed to operate the unit above the rated air discharge capacity pressure of the
unit.
Otherwise, the overload will occur to the motor and it will be damaged.
3. Before the unit is delivered, individual protection controls shall be set in a good condition. It is
never
allowed to modify or remove the control components of the unit. Otherwise, severe equipment
damages and injuries will be caused.
4. When the unit is operating, it is never allowed to remove or loose any pipeline elements,
joints and
connectors and to move the safety valve. The unit is full of the pressurized thermal working
medium,
which can cause the severe injuries.
5. Prior to any maintenance on the unit, It must confirm that:
 The unit is stopped;
 The internal pressure in the unit has been discharged;
 The power supply is shut off.
6. Only the safe solution is used to clean the unit's compressors and auxiliary equipment.
7. Once any parts are failed, they must be replaced immediately. Otherwise, the unexpected
loss may be caused.

Content
Chapter1 Safety Rules.....................................................................................
Chapter 2 Introduction to System Functions ...................................................
Chapter 3 Installation and Acceptance..............................................................
Chapter 4 Operating Procedures........................................................................
Chapter 5 Parameter Setting and Adjustment of Working Conditions .........
Chapter 6 Maintenance and Service..................................................................
Chapter 7 Troubleshooting

Chapter 1 Safety Rules
1. General rules
The following listed safety measures and safety precautions are only a part of the items which have to be
followed for operating the compressors and compressed air system, but are not complete.
Don’t change the internal structure and control mode of the unit, unless written permission from Screw Company
is given. The daily service and maintenance shall be performed well. The unit shall be carefully inspected daily to
check if conditions such as leakage, loose, damaged, and poorly adjusted parts, or missing parts and
components are present. If the problem is discovered, it shall be handled in time.
2. Common precautions
1) Before repairing the machine, all power supplies and any possible Long distance control devices shall be shut-
off, locked and identified.
2) If the unit is stopped, don’t assume that it is safe. As the unit has the automatic starting and stopping devices,
the starting is possible at any time.
3) The compressor is designed to compress the general air. Other gases or steams are not allowed to approach
to the inlet of the compressor or to flow through the compressor.
4) The safety relief valves with proper size shall be installed in the system and shall be located before the suction
valve, heat exchange, restriction orifice or any potential blockage points. If no safety relief valve is installed, the
damages of compressor or compressor parts or the explosion may be caused.
5) Don’t change the pressure setting of safety relief valve, or limit its function, or replace it with the plug. Other
wise the over-pressure will be caused to the compressor parts or system, consequently resulting in the injuries
and propert loss.
6) Don’t use the plastic pipe, rubber pipe or the brazed connecting pieces in the compressed air system. If the
matching between the compressor pipes and system pipes can’t be ensured, the harmful noises will be caused.
7) Don’t use the combustible or toxic solvent to clean the air filter or any components.
8) When the compressor is operating, don’t remove any protection cover or outside board. It is prohibited to
repair any parts in the unit when the machine is operating.
9) When the compressor is operating, it is noted to observe the meters and record, ensuring the normal operation
of compressor.
. Prior to any operations, the operation manual shall be carefully read and its contents shall be comprehensively
understood. If you fail to follow the operation and maintenance procedures and safety rules in the operation
manual, accidents and injuries are possible.
It is never allowed to start the unit in an unsafe condition; if the problems occur to the unit, don’t attempt to start
the unit. The power supply shall be shut off and the significant sign shall be given to prevent the person not
knowing the condition from wrongly operating.
Warning
If you fail to follow the following safety measures, the injuries, property loss or compressor damages will
be caused.
Only the trained and authorized persons are allowed to operate the compressor
The compressed air is hazardous. Only when the compressed air is totally discharged in the whole
compressor system, the maintenance and service can be performed on the unit.

9
10) Follow the stipulations in the maintenance and repair procedures and periodically inspect all safety
devices, ensuring that they are in a good condition.
11) It is never allowed to have the high-temperature protection switch (probe) with the short circuit, blockage
or being removed.
12) It is prohibited to play with the compressed air, to avoid the risks occur.
13) Follow the maintenance and repair procedures and apply the proper lubricating oil.
14) When the unit is operating, don’t open the cover, to avoid the leakage of noise or the scald caused by the
hot surface of the unit.
15) Before installing the outside box, it shall ensure that no one is inside the unit.
3. Pressure releasing
1) Open the safety valve at least once every week and inspect whether the blockage or other damage is
present. It is not allowed to pull the handle of the safety valve when the unit is pressurized.
2) Confirm that the installed pneumatic equipment, air hose, pipe fittings, valves, filters and other accessories
are in a good condition and the operating pressure during operation is not above the rated pressure.
3) Before opening the oil filling capo foil-gas separator tank, the machine shall be stopped and it shall ensure
that no pressure is present in the tank.
4) When removing any pipe fittings, valves, and oil drain plugs as well as the parts and components such as
oil filters and oil-gas separator, it shall ensure that no pressure is present inside the system.
5) Don’t operate against any air vents, regardless of the outlets of air supply pipes or the air vents of
compressors or pneumatic equipment.
6) Only the compressed air with the pressure below 30psi (2.1bars) can be applied for dust removal. During
the actual operation, the protection equipment such as dust protection cover shall be equipped. It is allowed
to use the compressed air with the pressure above 3 bars for maintaining the element of air filter; but it shall
ensure that the compressed air won’t directly flow to the persons. The associated persons shall perform the
necessary protections.
4.Operating components
1) The hands, arms and other body parts as well as the clothes shall not touch the operating components,
such as coupling, fans and etc.
2) After the protection covers at the fan, the coupling or other components are removed, don’t operate the
compressor.
3) During the operation, especially in a place near the high-temperature surface or operating components, the
close clothes shall be worn and the long hair shall be tied up.
4) The door on the unit shall be closed unless it is for maintenance.
5) It shall be ensured that no one is inside the unit for starting it.
6) The lubricating oil shall be filled only after the machine is stopped.
7) It is possible to require adjusting the capacity regulating valve or pressure switch some time when the unit
is operating. During the adjustment, don’t touch other operating components and charged bodies. Other
adjustments shall be made only after the machine is stopped.
8) The oil and water stains on the hands, feet, unit parts and the ground surface surrounding the unit shall be
cleaned to prevent from slipping.
5. High-temperature surface, sharp corner and sharp edge
1) Don’t touch the hot oil, lubricating fluid and high-temperature surface as well as the sharp edge sand
corners.
2) Any part of body shall not face the air vents of compress or sand cooling fans.
3) When the operation or maintenance is performed inside the unit or surrounding the unit, the protection
equipment such as gloves, helms shall be worn.
4) The first aid box shall be equipped. The medical treatment shall be made immediately after the persons are
injuries.
Don’t neglect the tiny cut and scald which may cause the infection.
6.Toxic and irritant substances

1) If the compressed air produced by the compress or is directly applied for respiration or food processing,
then the severe injuries or death will be caused. The compressed air applied for the above purposes shall
meet the stipulations in the OSHA 29 CFR1910.134 or FDA 21XDE178.3570 standard.
2) Avoid the skin contact and swallowing the lubricating oil(fluid). If the skin contact is made in advertently,
then it shall be cleaned out with the soap water. If swallowing inadvertently, it shall turn to doctor immediately.
7.Hoisting
Priortothehoisting,itshallcarefullyinspectindividualconnectorstocheckifthecracksoccurattheweldsofbase,
if the cracks, deformation or corrosion occur to the parts and components, and if the fasteners are loose.
. It shall ensure that the selected hoisting equipment, hangers and riggings have a good performance and are
able to withstand the weight of the unit. If the weight of the unit is not clear, it can weigh the unit or consult the
local agent before hoisting.
. The hoisting hook shall have the safety detent which can securely catch the lugor hoisting chain.
. The unit shall be pulled with the rope to prevent the hoisted unit from turning or swinging.
. Don’t hoist the unit when the strong wind is present. After the compressor unit is hoisted, no one can stand
under it.
. After it is hoisted, the hoisting operator can’t leave the site.
. The unit can be hoisted to a sufficient height in stead of an excessive height.
. When the unit is lowered, the supporting faces hall have the proper hardness and strength.
. Before transportation, the base shall be fixed with the iron nails or bolts.

Chapter 2 Introduction to System Functions
Air Inlet
System
Airend
Separation
System
Oil Pump
Control System
Exhaust Port
1.Introduction
The AIM75-150EPM2 screw compressor unit, designed and manufactured by the Anest Iwata Motherson
Company, is a positive displacement type, single-stage and oil-injected double-screw compressor. The motor
is connected to the male rotor of compressor airend via the belt or elastic coupling to drive the compressor
rotating. The compressor airend is originally imported with excellent processing, and therefore the unit has
good dynamics, economical efficiency and reliability. The unit has the proper layout, complete functions,
simple operation and maintenance, and good appearance. The unit consists of the compressor airend, air
inlet system, air discharge system of compressor, cooling and lubricating system, air flow adjustment and
control system of compressor, instrument control panel, electrical and automatic protection system and etc. In
addition to the excellent acoustic absorbing material, the unit has the full-closed silent type design which can
reduce the noises of the unit to the minimum extent. All instruments, indicators and control devices are
centralized on the control panel for convenient operation; all components are installed on a high-strength steel
frame for a long-term stable and reliable operation. An illustration of a model is quoted in the manual for the
description of the system. For the structure of other models, please refer to the quoted illustrations in the
manual, as the structures and functions of individual systems are similar or alike. To maintain the best
operating status of your purchased or applied screw compressor unit, please read the details in Maintenance
andService Procedures in the operation manual. If you have the difficult problems which are not mentioned in
the operation manual, please contact the local agent of Anest Iwata Motherson Company or the After-Sales
Service Department of Anest Iwata Motherson Company.
Lubricant System
Canopy
Drive System

The connecting elbow of the air inlet system adopts the high-quality molded rubber pipe fittings, which have the
properties of relatively good cold resistance, heat resistance and aging resistance. To ensure reliable sealing, all
the joints in the air inlet system of the unit shall have the stainless steel T-type bolt clamp for connection.
Fig. 2-1 Introduction to the 75/150EPM2 compressor system
2. Compressor airend and compression cycle The compressor airend is a very important component in the
Anest Iwata Motherson compressor unit. The carefully designed single-stage oil-injected cooling and
lubricating screw compressor can provide the stable compressed air without air flow ripple. Compared with
other brand compressor airends, the unique property of the end selected by the Screw is the extremely high
mechanical reliability and durability, and the working component achieves requirements of the “inspection-
free” process. In addition, no frequent maintenance and internal inspection are required during operation. In
the outside box of compressor airend, there is a pair of parallel rotors (male rotor and female rotor) with spiral
slots, which are finely processed. The air inlet and outlet are provided in the diagonal positions of the outside
box at both ends of the rotors. The threaded slot of female rotor engages with the threaded teeth of male
rotor, and it is driven by the male rotor. During operation, the air flows into the outside box via the air inlet at
the power input end. When the rotor turns through the edge of suction hole in the outside box, part of
suctioned air is trapped into the enclosed volume which is formed by the female and male rotors and the
outside box. The closed volume of threaded slot changes with the engaging movement of the female and
male rotors, and consequently the continuous operation cycle for suction, closing, compression and discharge
will be realized. The compressed air will be discharged via the air vent and then enter into the oil-gas
separator.
3.Air inlet system
See Fig. 2-2, the function of air inlet system in the compressor unit is to provide clean air to the compressor. It
includes an air filter, a suction valve and connecting pipeline. At the outlet of the air filter, a vacuum pressure
switch or vacuum indicator is installed.
The air filter adopted in the unit is the dry heavy duty filter, which can be used in the extremely severe
operating environment to handle the very dirty air, ensuring the normal operation of the compressor. In
addition to the main filter core, there is a cyclone separating blade ring outside the main filter core in the
outside box. It can pre-filter the relative coarse dust particles. The operators shall frequently remove the dust
particles accumulating in the dust bag at the rear cover of air filter. When the vacuum pressure switch in the
air filter acts or the vacuum indicator turns to red, it indicates that the flow resistance in the air filter is too high
and the main filter core shall be maintained or replaced in time. In addition, some models have a safety filter
core, which has the function for temporary protection in a short-term in the case that the main filter core is
damaged. The safety filter core usually requires no maintenance and shall be replaced only while the main
filter core is replaced.
Caution: The aperture of safety filter core is larger than that of main filter core. It only has the function of temporary
protection in a short term (4-6 hours) after the main filter core is failed. Therefore, once it is found that the main
filter core is failed, it shall be replaced immediately. Otherwise, it may cause accidents such as the worn of the
compressor rotors, damaged bearings and etc.

Warnin
g
Never use the iron wire to tie the rubber pipe fittings or use the rubber pipe fittings with
cracks.
① ②③ ⑤
Air Filter
Assembly
Hoop ④ AirInletGuidePipe Fig.
2-2 Air inlet system
Suction
Valve
4. Air discharge system of compressor
The air discharge system of compressor unit mostly consists of air discharge pipe, oil-gas separator, minimum
pressure valve, safety valve, after-cooler and etc. See Fig. 2-3.
When the compressor is operating, the air inside the closed room of threaded slot is continuously compressed
and the heat generated in the air during the compression is absorbed at the same time by the lubricating oil which
is continuously injected into the closed volume of threaded slot. When the closed volume of threaded slot is
reduced to a certain value (designed value), the closed volume of threaded slot is connected to the specially
designed air vent, and the mixture of oil and air is discharged out of the air vent. As the pair of rotors in the screw
compressor have several threaded slots and the rotating speed of rotors are very high, the air discharge of the
unit is continuous. The mixture of oil and air discharged from the compressor airend enters into the oil-gas
separator. Most oil is separated from the air by the catching, collision and direction change in the separator. The
formed oil drops accumulate to the relative large particles which will fall into the lower part of the tank by the
gravity. Only some very fine oil mist is left. When the air flows through the filter core of oil-gas separator, the oil
mist will congeal to the fine oil drops on the fibers of filter core by the collision, dispersion and catching. The oil
drops congealing on the outer fibers of filter core will fall to the oil level in the lower part of the cylinder by the
gravity, while the oil drops congealing on the inner fibers will finally be collected in the bottom of filter core. A
secondary oil return pipe is led from the bottom of filter core and connected to the suction chamber of
compressor. The oil accumulating in the bottom of filter core will flow back to the suction chamber of compressor
under the action of pressure differential. The throttle orifice is installed in the oil return pipe. The throttle orifice is
confirmed by test and will ensure both the stable oil return and the minimum air loss.
Therefore, the modification is not allowed unless it is permitted by Anest Iwata Motherson Company.
A minimum pressure valve is installed in the downstream of the outlet of oil-gas separator tank and its function is
to ensure that a minimum tank pressure will be established in the tank when the compressor is normally
operating, ensuring the normal operation of the lubricating oil circuit. When the unit is stopped or unloaded, the
minimum pressure valve acts as a check valve to prevent the return flow of compressed air. The unsealing
pressure of minimum pressure valve is 4.0±0.34bars (60±5psi), which has been pre-set before leaving factory.
The compressed air after oil-gas separating only contains several PPM (usually below 3PPM) lubricating oil. After
the separated compressed air flows through the minimum pressure valve, it will enter into the after-cooler for
cooling down and then can be used by the users.

The after-cooler is applied to reduce the discharge temperature of compressed air and consequently make most
of water in the compressed air condense and separate, reducing the water content in the compressed air and
avoiding the problem caused by water content in the downstream air.
Due to the different cooling method, the after-cooler is classified into two types: air cooling and water cooling. The
air cooling after-cooler is connected to the oil cooler to be integral. The fan drives the cooling air to flow through
the surface of cooler for cooling.
The water cooling type after-cooler and oil cooler usually are connected in series. The cooling water flows through
the after-cooler at first and then enters into the oil cooler.
A safety valve is installed on the cylinder of oil-gas separator tank. When the pressure inside the tank exceeds
the setting pressure of safety valve, the safety valve will automatically open. The unsealing pressure safety valve
is set before the delivery. Please do not change it by yourself. A temperature sensor is additionally installed in the
air discharge pipe. When the discharge temperature of compressor exceeds 110 ℃ (230°F), the unit will
automatically stop.
The screw-plug of oil filling port in the oil-gas separator is specially designed and can release the possibly
remained pressure in the tank when it is removed. The oil sight glass installed on the cylinder is applied to inspect
the level of lubricating oil in the tank. When the machine is not operating, the normal oil level shall be located
between the center of oil sight glass and its top position.
5. Cooling and lubricating system of compressor
The lubricating oil in the system has the following three main functions:
A) It acts as the coolant. The injected lubricating oil can absorb a large amount of the heat generated during the
compression, and consequently control the temperature rise of compressed air.
B) It fills the leakage clearances between the rotor and outside box and between rotors, reducing the internal
leakage of compressed air and increasing the efficiency of compressor.
C) The lubricating oil film is formed between rotors. It allows the male rotor to directly drive the female rotor and
can absorb some mechanical noises at the same time.
D) It’s used to cool down the liquid cooling PM motor.
See the flow chart in 2-4. Generally, the cooling and lubricating system of compressor consists of oil-gas
separator, oil cooler, oil filter and oil pipes, etc. The cooling fan is controlled by inverter, the inverter will
automatically control the fan motor speed according to the setting temp. in the PLC in order to maintain the
constant temp.
Warning
When the compressor is operating or pressurized, do not remove the nuts, oil filling cap and other parts. Before
maintenance, the machine should be stopped and all internal pressure should be released.
It is not allowed to replace or use the safety valve with other models.

Fig2.3 Compressor Cooling and Lubricant System
The oil filter consists of a filter base and replaceable spin-on filter core (depending on the size of the model, there
may be two or three filter cores) with a built-in by-pass valve which will ensure the unblocked oil circuit and
normal operation of the compressor in case that the filter core is dirty or the viscosity of the oil is too high.
The oil cooler is an important part of the cooling and lubricating system. Due to different cooling methods, it can
be classified into two types: air cooling and water cooling. A brief description is given below.
Air cooling type oil cooler: the cooler has an aluminum plate-fin type structure. The cooling fan forces the air to
flow through the fins of the cooler and cool down the lubricating oil in the pipes of the cooler. To maintain the
normal

operation of compressor, the radiating fins of cooler shall be kept clean and the maximum operating ambient
temperature of compressor shall not exceed 43℃. During the daily maintenance, the surface of cooler shall be
periodically cleaned. If necessary, the high-temperature pressurized water not above 3.5 bars can be applied to
wash it.
Water cooling type oil cooler: the water cooling type oil cooler has the shell and tube type structure. The
lubricating
oil flowing in the shell transfers most heat via the pipe wall to the cooling water flowing through the pipes. Similar
to the air cooling model, the lubricating oil flows through the thermostatic valve first and then enters into the cooler
for cooling down, ensuring that the unit operates in the normal temperature between 80~95℃ (176~200°F).
6. Air flow adjustment and control system of compressor
This series EPM2 compressor is equipped with standard automatic control system.
For compressor below 100HP, as long as you press “Start” button, it will start to load, according to the line
pressure,
it will adjust frequency automatically to produce the compressed air which match up with the air consumption.
When the system pressure reach unloading pressure(normally, it’s VF pressure+0.6BAR ） ， It will force the
suction
valve to close, the compressed air inside oil/air tank will be released out completely, the compressor will stop
automatically.
The compressor will enter into standby mode 。 When the system pressure reduce loading pressure （ Normally,
it’s VF
pressure -0.7BAR) ， the compressor will start automatically 。
For >100HP compressor, there have two option: manual control and automatic control. Customer could select
loading or unloading under manual control mode. When automatic control is selected , the compressor will
continue work
and produce the required air relying on the differential pressure regulator . When the pressure reach unloading
pressure(normally, it’s VF pressure + 0.6BAR) ， the controller will send message to make the suction valve
close, and
release all the compressed air inside oil/air tank, the compressor keep running, but don’t produce compressed
air 。 The
timer is triggered, the compressor will enter into countdown of unloading ， after the end of the time cycle, the
compressor
will stop automatically and enter in to “Standby”Mode. When the line pressure decrease to loading
pressure(normally, it’s
VF pressure+0.7BAR) ， The controller will send “Start up”Message, the compressor will start up automatically.
Please refer to Fig. 2-4 for system flow.
For ≤100HP EPM2 compressor, the compressor have three working mode ： A.Start up Mode, B.Stop Mode, C.
Standby Mode.
For >100HP EPM2 compressor, The compressor have four working mode: A. Start up mode, B. Loading Mode,
C.
Unloading mode, D. Stop & Standby Mode.
The compressor parameters have been set well in the factory, there’s no need to set parameters for client, unless
the
working condition has changed, and it will need authorized people to re-set the parameters.
The compressor take use of controlling the degree of opening of the intake valve to control the amount of intake
air
of the compressor in order to achieve the purpose of adjusting the volume. There are four working status: A. Start
up
condition; B. Loading condition; C. VSD control condition; D. Standby condition. The following nominal pressure
8bar
(116psi) models were introduced as an example of its working principle.
Warning

Do not think if the compressor is not operating, then the maintenance operation on it will be safe, as the compressor may be
in the “Standby” status and can start at any time. Please strictly follow all related stipulations in “Maintenance and Service
Procedures”.
6.1 Working conditions of starting
For >100HP compressor: Press the start button, the motor VSD start up, the compressor suction valve opens a
small
amount of air at the moment the action of vacuum. At this point, solenoid valve 1,3 port held in communication,
while
vent valve is opened so that the oil/air tank is vented state, instant boot small amount of air sucked through the
solenoid
valve into force it to close the intake valve, the intake valve plate holes (or the valve plate and the valve body
between a
small gap) allow a small amount of air into the compressor, making it essential to maintain the pressure within the
1.5-3.5bar (22-51psi) range. The compressor start up with light load. Solenoid valve and vent valve is closed, the
intake
valve fully open, compressor loading operation, the system pressure rapidly rise to 4.0bar (60psi).
For ≤ 100HP compressor: press the start button, the motor VSD start up, the compressor intake valve opens in
an instant
vacuum effect, the machine enter into a loading state
6.2 Loading State
When the system pressure exceeds 4.0bar (60psi), minimum pressure valve opens, the compressor start to
discharge
compressed air out. The suction valve is fully open, the compressor work at loading state. Subsequently, the
system
pressure will soon reach the rated pressure, the unit enters normal operating conditions. Unless the customer air
consumption is changed, the compressor will run continuously in this state.
6.3 Working at adjustment state
When air consumption is less than the rated displacement, the system pressure will rise. When the pressure
exceeds the
rated pressure of 0.01 to 0.02Bar, The inverter will reduce frequency to reduce the motor speed. If the time of the
compressed air demand increases, the pressure within the oil/air tank will drop. When the pressure drops below
the rated
pressure set value, the inverter frequency increases, so the compressor run at full capacity again.
6.4 Unloading & Stop State
For > 100HP compressor: When the customer air consumption continues to decrease to 20% less than the
nominal
displacement compressor, line pressure will exceed PLC setting 8.6bar (125psi), this time, the compressor will
turn into
unloading state, relying on a small amount of the intake valve bypass pipe intake air pressure is maintained within
the unit
1.5 ~ 3.5bar (22-51psi) range to ensure that the internal oil lubrication system oil circulation. Within this pressure
range,
minimum pressure valve is closed, the compressor will run at a unloading state.
For ≤100HP compressor: When the line pressure exceeds the PLCS setting 8.6bar (125psi), The PLC will send
stop
message, the compressor will stop running, enters into standby state.
For > 100HP compressor: If air consumption increases, the line pressure drop. When the pressure is lower than
7.3bar (106psi), the PLC will send loading message, the solenoid valve will be activated and the vent valve will be
closed,
the compressed air inside oi/air tank will stop releasing, the suction valve will open, so the compressor will enter
into
loading state automatically .
For ≤100HP compressor: When the line pressure is lower than 7.3BAR(106PSI), the PLC will send start message
to
start up compressor again.

7. Electrical system and automatic protection
See Fig. 2-6. Electrical system is the system which realize compressor start, stop, parameter display and
automatic
protection. The system includes the motor, industrial control panel, instrument, contactor, transformers, cables
and
terminals, inverter and various protection switch etc.
“Caution”: The related documents are attached when the unit leaves factory. To avoid mis-operation,
please refer to the
electrical schematic diagrams attached to the machine for the maintenance and service of electrical system.
Standard liquid motor is totally enclosed, protection grade is IP54/IP65, maximum ambient temperature is 43 ℃
(110 ℉). This standard does not apply to saline, corrosive, dirty and wet and explosive situations.
Fig. 2-4 System Flow
Automatic protection is an important part of the compressor. Its role is to ensure that the compressor is not
under normal circumstances, then it can not start or will stop automatically, and thus play a security role for
the airend and the motor. The features include: Compressor discharge temperature shutdown protection, high
pressure shutdown protection, motor overload protection, motor short current protection, lack phase
protection etc. When the compressor operate normally, in addition to the safety valve, other automatic
protection devices can make the


compressor stop, when these unexpected situation happen,the compressor will stop automatically, and send
fault message.
Warning
:
Warnin
g
High voltage will cause severe injury and death. Please cut down the power supply before maintaining the electrical
apparatus or opening the electrical control box.
Do not remove, bridge, or damage the high-temperature safety switch. If the safety function is not provided, severe injuries,
death and property loss may be caused. If the machine is shut off due to the over-high temperature, please contact the
qualified service persons immediately.

Chapter 3 Installation and Acceptance
Fig. 3-1
2.Installing and locating
The series of compressor units are applicable to the indoor environment. Place the compressor in a clean
environment with good lighting and ventilation, and the foundation shall be solid and flat. The whole base shall
tightly fit the horizontal level of foundation. If necessary, the hard rubber cushion can be shimmed. However, it is
noted that no wood wedge is used. For the safety and simple maintenance as well as the daily inspection, the
sufficient space shall be provided around the machine (At least 1.2m space shall be left around and above the
compressor). The operating ambient temperature of compressor can’t exceed 43 ℃ (110 ℉). Otherwise, the
compressor will be shut
1.Installation, acceptance and storage:
In the process from the delivery of machine to the installation in position on site, the correct shutdown
maintenance and service contribute to the completion and normal operation of equipment. Therefore, the machine
shall be inspected immediately for the damages caused during transportation when it is received. If the damages
are found, the carrier can be required to sign on the shipping document and give the damage report. If the
damages are not found in time and then the hidden damages are found afterwards, please inform the carrier
within 15 days after receiving the goods and require the carrier to give the damage report. The detailed report is
very critical for handling the damages (claim). Check the nameplate of compressor to ensure that it has the model
number and specifications you ordered and check whether optional parts are included. In addition, inspect the oil-
gas separator and safety valve to confirm whether the design or pressure setting is correct. The protection and
maintenance solutions shall be prepared for the unit which will not be installed temporarily or operated for a long
term, ensuring the normal operation of the unit, especially the airend of main machine.
The handling and installation of unit shall strictly follow the precautions related to handling after the packaging
box is opened. Two holes for fork lifter are set under the base of unit. When it is lifted, the supporting block shall
be placed to prevent the fork lifter from crushing the door plate of unit (shown as the figure). If the lifting rope is
used, the cross bar has to be applied, which can counteract the lateral pressure against the box caused by the
lifting rope.
Note: It is not acceptable to place some protection materials between the lifting rope and the outside box of unit. It
will crush the door plates at both sides in the top of unit.

: “Caution”
Removing or modifying the outside box will cause the high noises and consequently be harmful to human health.
The screw compressor has a stable operation and basically no vibration. It can be naturally placed without anchor
connection. However, if it is necessary for the user, the compressor can be fixed with bolts to prevent the pipes
from breaking or prevent the electrical connection from being damaged due to the displacement of machine
caused by the collision. In this point, it is noted that the bolts shall not be tightened excessively to prevent the oil
cooler, pipes and air tank from cracking and being damaged due to the distortion and deformation of machine
base caused by the excessively tightened bolts.
down due to over-heat. The spatial dimensions and shape of compressor room shall be carefully considered, to
prevent the hot air discharge capacity by cooling fan from circulating in the machine room and consequently
causing the rising of operating ambient temperature. In principle, all stationary type screw compressors from
Screw are provided for indoor installation and application. The modified ones can also be installed in the outdoor
places. The machine cover shall be water-proof and not sealing, preventing from rainwater, snow and freezing.
If the working condition for operation is relatively poor and there are much dust, then the specially configured
heavy duty air filter shall be added to maintain the service life of air compressor system and parts.
Please refer to relevant regulation for Design of Compressed Air Station.
3. Storage and maintenance of the unit
The screw compressor unit is specially designed, especially for the airend of main machine, which is precisely
machined and formed. The operating procedure and requirements from the manufacturer shall be strictly followed
for the maintenance and service. Otherwise, the property losses and injury accidents may be caused. If the unit
will be stored for a long time or will be out of service for a long period, then it shall ensure at first that it is placed in
a clean and dry
Do not place the compressor in the environment where it may suction the high-temperature waste gas discharged
by other compressors or thermal load equipment. Do not block the cooling air discharge capacity of the air
cooling compressor, and it shall be guided to the outdoor, avoiding the excessive ambient temperature in the
compressor room. If the ventilation in compressor room is poor, the high-temperature shut-down of machine may
be caused. Moreover, don’t place the compressor in the basement or the places with poor ventilation. If the
possibility of oil pollution caused by the water is considered, the operating temperature of compressor shall be
controlled and the lubricating oil of compressor shall be monitored.
The normal operation of compressor requires sufficient cleaning air.
The compressor can’t operate in the environment with the temperature below 0℃ (32℉) or above the maximum
operating temperature limit.
Do not install or expose the compressor to the places with toxic, volatile or corrosive gases. It is also not allowed to store
the substances with similar properties around it. Otherwise the severe injuries and property losses will be caused.
“Warning”
“Caution”
“Warning”

4.1.1 Points for attention in piping of air pipeline
1 ） For piping of main pipeline, a 1 to 2 inclination degree is required to facilitate the discharge of
condensation water in the pipeline.
2 ） The pressure drop of the pipeline shall not exceed 5 percent of the setting pressure of the air compressor
so it’s recommendable to select pipes with a larger diameter than the design diameter during piping.
3 ） The branch pipeline must be connected to the top of the main pipeline to prevent the condensation water in
the pipeline from flowing down to the machine or flowing back to the air compressor.
4 ） A combination of three devices including water filter, pressure regulator and oil feeder shall be installed on
the tools that require lubrication to maintain their service life.
5 ） Don’t reduce the size of the main pipeline randomly. If the reduction or enlargement of the pipe is required,
a reducing pipe must be adopted or the mixed flow may occur at the connection which will lead to a bigger
pressure loss and also exert a great influence on the service life of the pipeline.
6 ） If such clean and buffer facilities as gas holder and dryer are available, the ideal piping shall be air
compressor +gas holder + dryer. In this way, the gas holder may eliminate part of the condensation water and
also have a function of decreasing the exhaust temperature. The air with low temperature and less moisture will
definitely ease the load of the dryer.
environment. The accumulated water in the bottom of the parts and components such as oil-gas tank, cooler
(especially the water cooler), steam-water separator, pipeline water filter shall be drained out. Individual major
parts and components of unit and joints shall be inspected periodically and clean them to ensure no leakage and
rust signs. It shall start and operate for at least 60 minutes every month to ensure the safe lubrication in the
airend of main machine. Secondly, the careful inspection is required before it is started. If necessary, the
lubricating oil shall be replaced in the unit. In addition, 2-hour operation test shall be performed at full load on the
unit and the data shall be recorded. The qualified specialized service engineer shall be present for instruction.
4. Pipe connection
No lead/tin solder is allowed in the connection of pipes or connecting pieces. The lead/tin solder materials have
the characteristics of low strength and can’t resist the high temperature. Their melting point is only 182℃ (360℉).
Therefore, please don’t mistake them for braze welding such as the silver solder and copper solder. In addition,
please note that no plastics, PVC, ABS pipes or rubber hoses are allowed in the piping system for compressed
air. It has to be noted that no rusty pipes will be installed on the compressor. The pipes shall be connected to the
proper position without bending and distortion. To avoid the effect of heat expansion of the pipes on the system,
some flexible expansion joints or hoses can be installed in the system, if necessary. The pipes shall be
independently supported and fixed to reduce the vibration and prevent the expansion and deformation. In any
cases, the size of pipes shall be no less than the connection size of discharge pipes in the compressor.
For the compressor, the cleaning air is critical. The air filter is indispensable. The air supply which can supply the
cleaning air shall be selected. If the outdoor air supply is used, then it shall ensure that all pipes are short and
straight. The pipes shall be properly laid out and the vibration shall be avoided. The diameter of pipes shall be no
less than the dimensions of suction valve. For the excessively long pipes, the diameter of pipes shall be
increased. In addition, the pipes shall prevent from leakage and shall be absolutely clean after they are installed.
4.1.Points for attention in piping, base and cooling system