Gardner Denver ELECTRA-SAVER II Service manual

/I)Price $5.00
D-
Q%
GARDNER-DENVER@ 13-9-642
1st Edition
ELECTRA-SAVERII@
STATIONARY
BASE-MOUNTED
COMPRESSOR
MODELS
40 &50 HP
ECH
INDUSTRIAL MACHINERY
ICOOPER
INDUSTRIES

FOREWARD
Gardner-Denver Electra-Saver Il” compressors are the result of advanced engineering and skilled manufacturing. To
be assured of receiving maximum service from this machine the owner must exercise care in its operation and
maintenance. This book is written to give the operator and maintenance department essential information for
day-to-day operation, maintenance and adjustment. Careful adherence to these instructions will result in economical
operation and minimum downtime.
DANGER
Failure to observe aDANGER notice could result in injury to, or death of personnel.
WARNING
Failure to observe aWARNING notice could result in damage to equipment.
CAUTION
CAUTION notices set forth general reminders of good safety practice, or direct
attention to unsafe practices.
NOT E
Information furnished in aNOTE will include general information or the highlights of
aprocedure.
This book covers the following models:
HP PSIG Air Cooled Water Cooled
40 100, 125 ECHQLE ECHSLE
50 100, 125 ECHQME ECHSME
150
TABLE OF CONTENTS
GENERAL INFORMATION .............................................................................................................................SECTlON 1
INSTALLATION ...............................................................................................................................................SECTlON 2
STARTING AND OPERATING PROCEDURES ..............................................................................................SECTlON 3
CONTROLS AND instruments .................................................................................................................SECTlON 4
LUBRICATION, OIL COOLER, OIL FILTER AND SEPARATOR ....................................................................SECTlON 5
AIR FILTERS ...................................................................................................................................................SECTlON 6
COUPLING ......................................................................................................................................................SECTlON 7
MAINTENANCE SCHEDULE ..........................................................................................................................SECTlON 8
TROUBLE SHOOTING ...................................................................................................................................SECTlON 9
13-9-642 Page i

INDEX
NOTE: Numbers preceding dash are Section Numbers -- Numbers following dash are Page Numbers
Addition of Oil Between Changes ..........................5-1
Adjustments .............................................................4.5
Air Control Components .........................................4-1
Air Filter Vacuum Switch .........................................4-3
AIR FILTERS (SECTION 6) .....................................6-1
Air Flow in the Compressor System .......................1-1
Auxiliary Accessories ..............................................2-3
Auxilia~ Air Receiver ...............................................2.3
Blowdown Valve ...............................................4.l. 4-3
Blowdown Valve Piping ..........................................2-4
Check Valve .............................................................4.2
Cold Ambient Operation .........................................5-1
Cold Weather Operation, Installation for ................2-2
Compression Principle ............................................1-1
Control Piping .........................................................2.3
CONTROLS &INSTRUMENTS (SECTION 4) ........4-1
Control Schematics ..................................4-6 thru 4-8
Control System Operation ......................................4-4
COUPLING (SECTION 7) .......................................7-1
Daily Check .............................................................3.l
Discharge Pressure Transducer ..............................4.3
Discharge Temperature, Air and Oil .......................5-4
Display, Controller ....................................................4.5
Draining and Cleaning Oil System .........................5-3
Electrical Wiring .......................................................2.5
Enclosure ................................................................2.2
Emergency Stop Button ........................................ 4-1
Filling Oil Reservoir .................................................5.3
Flow Diagram -- Air/Oil Systems ..............5-2. 5-3, 5-4
Foundation ..............................................................2.2
GENERAL INFORMATION (SECTION 1) ...............1-1
Grease Recommendations ....................................2-5
Grounding ...............................................................2.5
High Discharge Temperature .................................4-1
High Temperature Operation ..................................5-1
Inlet Line .................................................................2.4
Inlet Valve ...............................................................4.l
INSTALLATION (SECTION 2) .................................2-1
Lifting Unit ...............................................................2.l
Location ...................................................................2.l
Lubricant ..................................................................5.l
Lubrication, Cooling and Sealing ...........................1-1
LUBRICATION, OIL COOLER, OIL FILTER &
SEPARATOR (SECTION 5) ..................................5-1
MAINTENANCE SCHEDULE (SECTION 8) ...........8-1
Minimum Discharge Pressure Valve ......................4-2
13-9-642
Moisture in the Oil System .....................................5-4
Moisture Separator/Trap ........................................2-3
Motor Lubrication ...................................................2.5
Motor Protection Devices .......................................4-1
Oil Change Interval .................................................5.4
Oil Cooler, Compressor -Radiator Type ...............5-5
Oil Cooler, Compressor -Water Cooled .................5-6
Oil Cooler Oil Pressure Differential .............. . ..... 5-7
Oil Cooler Temperature Differential ...................... 5-7
Oil Cooler Water Pressure Differential ..................5-7
Oil Filter, Compressor ............................................5-5
Oil Inlet Pressure .................................................... 5-7
Oil Inlet Temperature ............................................. 5-7
Oil Level Gauge ......................................................5.4
Oil Separator (G-D Eliminator) ...............................5-7
Oil Specifications ....................................................5-1
Oil System Check .................................................. 5-7
Oil System, Compressor ........................................5-1
Pressure Differential Gauging ................................5-7
Pressure Regulator .................................................4.3
Prestart-up Instructions ..........................................3-1
Programmable Controller ...................................... 4-4
Programmable Controller Operation .....................4-4
Protective Devices and Shutdown .........................4-1
Purge Air Valve .......................................................4.2
Regressing Interval .................................................2.5
Relief Valve ..............................................................4.l
Reservoir Pressure Switch .....................................4-6
Safety Precautions .................................................. 1-4
Service Check List ..................................................8-1
Shuttle Valve ...........................................................4.3
Solenoid Valves -lVCand IVO ................................4-3
Solenoid Valves -TVCand TVO ..............................4-3
Starter/Control Panel ..............................................4-4
STARTING &OPERATING PROCEDURES
(SECTION 3) .......................................................3.l
Stopping Unit ..........................................................3-2
Synthetic Lubricants ...............................................5-l
System Pressure Transducer .................................4-3
Thermal Control Valve ............................................5-5
TROUBLE SHOOTING (SECTION 9) .....................9-1
Vibration Switch .......................................................4.3
Water Flow Control Valve for Heat Exchanger ......5-6
Water Piping ............................................................2.4
Water Shutoff Valve .................................................5.7
Wiring Diagrams .....................................................4.9
Page ii

SECTION 1
GENERAL INFORMATION
v
FIGURE 1-1 -COMPRESSION CYCLE
COMPRESSOR -The Gardner-Denver@ Electra-
Saver II compressor isasingle stage, positive displace-
ment rotary machine using meshing helical rotors to
effect compression. Both rotors are supported between
high capacity roller bearings located outside the com-
pression chamber. Single width cylindrical roller bear-
ings are used at the inlet end of the rotors to carry part
of the radial loads. Tapered roller bearings at the dis-
charge end locate each rotor axially and carry all thrust
loads and the remainder of the radial loads.
COMPRESSION PRINCIPLE (Figure 1-1) - Compres-
sion is accomplished by the main and secondary rotors
synchronously meshin in aone-piece cylinder. The
main rotor has four (4 helical lobes 90 apart. The
secondary rotor has six (6) matching helical grooves 60°
apart to allow meshing with main rotor lobes.
The air inlet port is located on top of the compressor
cylinder near the drive shaft end. The discharge port is
near the bottom at the opposite end of the compressor
cylinder. Figure 1-1 is an inverted view to show inlet and
discharge ports. The compression cycle begins as
rotors unmesh at the inlet port and air is drawn into the
cavity between the main rotor lobes and secondary rotor
grooves (A). When the rotors pass the inlet port cutoff,
air istrapped inthe interlobe cavity and flows axially with
the meshing rotors (B). As meshing continues, more of
the main rotor lobe enters the secondary rotor grove,
normal volume is reduced and pressure increases.
v
Oil is injected into the cylinder to remove the heat of
compression and seal internal clearances. Volume
reduction and pressure increase continues until the
air/oil mixture trapped in the interiobe cavity by the
rotors passes the discharge port and is released to the
oil reservoir (C). Each rotor cavity follows the same
“fill-compress-discharge” cycle in rapid succession to
produce adischarge airflow that is continuous, smooth
and shock free.
AIR FLOW IN THE COMPRESSOR SYSTEM (Figure
1-5) -Air enters the air filter and passes through the inlet
unloader valve to the compressor. After compression,
the air/oil mixture passes into the oil reservoir where
most of the entrained oil is removed by velocity change
and impingement and drops back into the reservoir. The
air and remaining oil then passes through the separator
where most of the oil isremoved. The air passes through
the discharge check valve, minimum pressure valve and
aftercooler, then to the plant air lines.
LUBRICATION, COOLING AND SEALING -Oil is
forced by air pressure from the oil resetvoir through the
oil cooler, thermostatic mixing valve, and oil filter and
discharge intothe compressor main oil gallery. Aportion
of the oil is directed through internal passages to the
bearings, gears and shaft oil seal. The balance of the oil
is injected directly into the compression chamber to
remove heat of compression, seal internal clearances
and lubricate the rotors.
13-9-642 Section 1Page 1

.
STARTER
CONTROL
BOX
o
.-EMERGENCY STOP
EMERGENCY STOP
\
‘“E”D”cONTROLpANEL1\
CONTROL TRANSFORMER
\ \ \
FIGURE 2-1
DRIVE MOTOR 7
~__ —---
0
FIGURE 3-1
—MAIN MOTOR
STARTER
‘FAN MOTOR
STARTER
FIGURE 4-1
13-9-642 Sectionl Page2

MINIMUM
PRESSURE
CHECK VALVE
DISCHARGE -7
VALVE \\
““NG‘ALvE\\\ To”“’TER
OIL CO OLERm
FIGURE 5-1
INLET VALVE 1
COMPRESSOR ~
(L
.—.--.—.-—
—COUPLING GUARD
-OIL LEVEL GAUGE
4
I
I
I
J
FIGURE 6-1
13-9-642 Section 1Page 3

SAFETY PRECAUTIONS
Safety is everybody’s business and is based on your use of good common sense. All situations or circumstances
cannot always be predicted and covered by established rules. Therefore, use your past experience, watch out for
safety hazards and be cautious.
Some general safety precautions are given below:
WARNING
Failure to observe these notices could result in damage to equipment.
.Stop the unit if any repairs or adjustments on or around the compressor are
required.
●All compressed air supply hoses exceeding 1/2 inch inside diameter should
have an excess flow valve. (OSHA Regulation, Section 1518.302)
.Do not exceed the rated maximum pressure values shown on the nameplate.
.Do not operate unit if safety devices are not operating properly. Check
periodically. Never bypass safety devices.
DANGER
Failure to observe these notices could result in injury to or death of personnel.
.Keep fingers and clothing away from revolving fan, drive coupling, etc.
●Do not use the air discharge from this unit for breathing -not suitable for
human consumption.
●Do not loosen or remove the oil filler plug, drain plugs, covers, the thermo-
static mixing valve or break any connections, etc. in the compressor air or
oil system until the unit is shut down and the air pressure has been relieved.
.Electrical shock can and may be fatal.
.Compressor unit must be grounded in accordance with the National Electri-
cal Code. Aground jumper equal in size to the equipment ground conductor
must be used to connect the compressor motor base to the unit base.
.Fan motors have been and must remain grounded to the main base through
the starter mounting panel in accordance with the National Electrical Code.
.Open main disconnect switch before working on the control.
.Disconnect the compressor unit from its power source before working on the
unit -this machine is automatically controlled and may start at any time.
13-9-642 Section 1Page 4

SECTION 2
INSTALLATION
GENERAL -On receipt of the unit, check for any
damage that may have been incurred during transit.
Report any damage or missing parts as soon as pos-
sible.
CAUT ION I
Do not electric weld on the compres-
sor or base; bearings can be damaged
by passage of current.
LIFTING UNIT -Proper lifting and/or transporting
methods must be used to prevent damage. -
CAUTION
Liftcompressor unit by base onl .Do
not use other places such as
enclosure, motor, compressor oil dis-
charge manifold and piping as lifting
points.
DANGER
The eyebolts or lugs provided on the
motor are for Iifting the motor only and
should not be use to lift any additional
weight. All eyebolts must be securely
tightened. when
lifting the motor the
Iifting angle must not exceed 15
degrees. failure to observe this warn-
ing may result in damage to equipment
or personal injury.
Lifting slots are provided in the base for towmotor use.
Unit may also be moved into location by rolling on bars.
LOCATION -The compressor should be installed,
whenever possible, in aclean, well-lighted, well-venti-
lated area with ample space all around for maintenance.
Select alocation that provides acool, clean, dry source
of air. In some cases it may be necessary to install the
air filter at some distance from the compressor to obtain
proper air supply.
Both the air-cooled and water-cooled units require cool-
ing air as well as air to the compressor inlet. Proper
ventilation MUST be provided; hot air must be exhausted
from the compressor operating area. Atypical inlet-out-
let air flow arrangement is shown in Figure 1-2.
AIR-COOLED UNIT -Acombination oiI/aftercooler is
supplied as standard equipment on all air-cooled units.
The air-cooled unit with the standard enclosure requires
sufficient flow, Figure 2-2, for the compressor oil/after-
cooling system and for electric motor cooling. Air is
drawn into the unit at the motor side of the enclosure
and is exhausted at the oil cooler side. Do not block the
air flow to and from the unit. Allow three and one-half
(3-1/2) feet to the nearest obstruction on the starter end
and control box end of the unit. Allow three (3) feet to
the nearest obstruction above and on other sides of unit.
For continuous efficiency, oil cooler cores must be pe-
riodically cleaned with either vacuum or compressed air.
If wet cleaning is required, shield motor and spray on a
mild soap solution and flush with clean water.
WARNING
For aluminum oil coolers, do not use
any cleaning solution that is not com-
patible with aluminum. Use of im-
proper solution may result in damage
to cooler.
WATER-COOLED UNITS -The water-cooled unit with
the standard enclosure requires sufficient air flow, Figure
2-2, for electric motor cooling. Air is drawn into the unit
at the top ofthe enclosure and is exhausted at the motor
side. Do not block air flow to and from unit. Allow three
and one-half (3-1/2) feet to the nearest obstruction on
the starter end and control box side of the unit. Allow
three (3) feet to the nearest obstruction above and on
other sides of the unit.
FOUNDATION -The Electra-Saver II@compressor re-
LOUVERED EXHAUST FAN LOUVEREO
wINDOW WINOOW
Ik~”’ “
.: ...‘,,>....
:\I I
tSIR OUT
14
,,
...’....+ .4 . .. .. .. . . . ,
A75119
FIGURE 1-2- TYPICAL COMPRESSOR ROOM
IMinimum Air Flow* For Compressor
And Cooling (Cubic Feet/Minute) I
Air Cooled Water Cooled
All Models 6000 cfm 1700 cfm
1II1
*60”F inlet air.
FIGURE 2-2
13-9-642 Section 2Page 1

MO TORm ~COMPRESSOR r8FT PLYWOOD “FENCE- 8FT. PLYWOOD ““FENCE’”
-WFLLMAN RADIANT 2–ELEMENT
(OR EOUAL)
:;;c ‘:’?:!:sO’ b4FT.
r-./ HEATER (
RH4m WI
ELEMENT
3.200 WA, ,, .n~n
‘-\ /
P
rr
‘+_
OIL RI SERVOIR \
\
LAWAY fROM PREVAILING WINOS L~~~~~~~ ~*o,A~T 2-~L~~~~~
HEATER (OR EOUAL) ELEVATION VIEW
RH7W WITH [2) RH7502
ELEMENTS -2REOO.
6.200 WATTS EACH
FIGURE 3-2- COLD WEATHER INSTALLATION
quires no special foundation, but should be mounted on
asmooth, solid surface. Whenever possible install the
unit near level. Temporary installation may be made at
amaximum 10° angle lengthwise or 10° sidewise.
Mounting bolts are not normally required. However,
installation conditions such as piping rigidity, angle of
tilt, ordangerof shiftingfrom outside vibration or moving
vehicles may require the use of mounting bolts and
shims to provide uniform support for the base.
OIL RESERVOIR DRAIN -The oil drain is piped from
the bottom of the reservoir to the side of the frame. This
drain is approximately 4.5o inches above the floor level.
If this is not sufficient to conveniently drain the oil some
other methods of providing drain are:
1. Elevate the compressor unit on raised blocks to
obtain the desired drain height.
CAUTION
If the compressor unit base is raised
above floor level, the space between
the floor and the base bottom must be
closed with solid material all around to
prevent recirculation of hot air from the
oil cooler end and over temperature
operation.
2. Construct an oil sum or trough below the floor
P
level and pump or bai the drained oil.
3. Pump oil from the reservoir filler opening or drain
to acontainer.
ENCLOSURE -The compressor, electric motor, oil
cooler and aftercooler are mounted inside the
enclosure.
Service doors are provided for maintenance access. Be
sure to allow enough space around the unitfor the doors
to open completely.
Any ofthe enclosure doors maybe removed by opening
the door and lifting itup slightly to disengage the hinges.
The motor inspection/air filter service panel is held by
two latches and lifts away from the enclosure. The air
outlet panel is attached by screws to the enclosure and
is not readily removable.
INSTALLATION FOR COLD WEATHER OPERATION
-It is recommended that whenever possible the unit be
installed inside ashelter that will be heated to tempera-
tures above freezing (32”F, O“C). This will eliminate
many of the problems associated with operating the
unitsoutside incold climates where freezing rain, drifting
snow, freezing condensate and bitter cold temperatures
are encountered.
Refer to Engineering Data Sheet 13-9-411 for the ad-
vantages of using the heat recovered from rotary com-
pressors. This heat recovery could easily pay for an
adequate shelter for the unit.
When an outside installation must be made, the precau-
tions required will depend on how severe the environ-
ment. The following are general guidelines for outside
installations:
Cold Weather (Down To -10”F)
1. Be sure all control lines, drains and traps are heated
to avoid freezing of condensate. Heat tape with
thermostat control is generally satisfactory for this
purpose and can be obtained at various local
plumbing or hardware outlets at nominal cost.
2. Ifan air-cooled aftercooler isto be used, provisions
to bypass the aftercooler should be made. Since
cold air contains very little moisture, successful
operation can be achieved without the aftercooler.
3. Provide at least some simple shelter such as a
plywood windbreak to protect against drifting
snow.
4. Use only Gardner-Denver@ AEON ‘M 9000
lubricant.
13-9-642 Section 2Page 2

5. Monitor unit carefully during start-up and operation
to be sure it is functioning normally.
6. Specify NEMA 4enclosure for electrical devices.
Extreme Cold Weather Operation (Down To -40*F)
In addition to the above, the following should be
provided:
1. It will probably be necessary to provide shutters or
to block off part ofthe cooler in some manner since
the cooler isgreatly oversized for operation inthese
low temperatures. Since shutters are not provided
as a factory option, blocking off aortion of the
P
cooler with plywood should be satis actory.
2. Lo-Demand operation should not be used in ex-
treme environments.
3. Some means of providing heat to the oil reservoir
and cooler during shutdown should be provided.
There are various methods to accomplish this, but
since openings are not provided for sump heaters,
the use of radiant heaters is recommended. The
heaters should be sized to provide at least a-1O“F
environment for coolers motor and sump. Figure
3-2 shows how these might be located in atypical
installation and sizes required.
Remember unsheltered (outside) installations should be
avoided where possible. Installation next to aheated
building where enough heat can be used to keep the
compressor room above freezing will save many com-
plications in the operation and installation of the unit.
Refer to Engineering Data Sheet 13-9-411 for the ad-
vantages of using the heat recovered from rotary com-
pressors. This heat recovery could easily pay for an
adequate shelter for the unit.
AUXILIARY AIR RECEIVER -An auxiliary air receiver is
not required if the piping system is large and provides
sufficient storage capacity to preveni rapid cycling.
When used, an air receiver should be of adequate size,
provided with arelief valve of proper setting, apressure
gauge and ameans of draining condensate.
MOISTURE SEPARATOR/TRAP -Since unit is
equipped with abuilt-in aftercooler, acombination mois-
ture separator and trap is furnished with the unit.
CONTROL PIPING -External control piping is not
necessary since the Electra-Saver II unit is factory
wired and piped for the control system specified.
INLET LINE -Where an inlet line is used between the air
filter and the compressor, it must be thoroughly cleaned
on the inside to prevent dirt or scale from entering the
compressor. If welded construction is used, the line
must be shot blasted and cleaned to remove welding
scale. In either case, the inlet line must be coated
internally by galvanizing or painting with amoisture and
oil-proof sealing lacquer. Up to ten (1O) feet in length,
the inlet line should be the full size of the inlet opening
on the compressor. If an extra-long line is necessary,
the pipe size should be increased according to Inlet Line
Chart below.
INLET LINE LENGTHS
Length of Inlet Line Diameter of Pipe Size
Oto 10 Feet ...........................................................................................................Same as Compressor Inlet Opening
10t017 Feet ...........................................................................................................One Size Larger Than Inlet Opening
17 to 38 Feet. ........................................................................................................Two Sizes Larger Than Inlet Opening
-- OIL COOLER
Water Temperature To Heat Exchanger Maximum
Water
HP Model 60”F70”F80° F90”FFlow
40 ECHSKE 3.4 4.3 5.7 8.6 30.0
50 ECHSLE 4.1 5.1 6.8 10.2 30.0 =
Approximate Water
Pressure Drop 090”F
Water Flow (PSI)
1.0
1.5
IAFTERCOOLER I
Water Temperature To Heat Exchanger Maximum
Al1owable
HP Model 6o°F70”F80”F90”FFlow (GPM)
40 ECHSKE 0.5 0.7 0.9 1.3 26.0
50 ECHSLE 0.7 0.9 1.2 1.8 26.0
Approximate
Water Pressure
drop
flow ratesare based on 110*F maximum allowable outlet water temperature. Higher water outlet temperatures
can lead to heat exchanger malfunction by causing fouling in the last water pass.
FIGURE 4-2- HEAT EXCHANGER (OIL COOLER-AFTERCOOLER)
APPROXIMATE WATER FLOW -U.S. GALLONS/MINUTE
13-9-642 Section 2Page 3