Gardner Denver ELECTRA-SAVER II Service Manual page 19

Safety Valve (Figures 2-1 & 3-1) - A pressure relief valve is
installed in the final discharge manifold and set at the
factory to approximately 120% of the specified operating
pressure for protection against overpressure. Periodic
checks should be made to insure its proper operation
Never operate the unit without a proper safety valve setting
Low Demand Mode Pressure Switch (Figure 1-4) - The
low demand mode switch when turned ON will cause the
low demand mode pressure switch to reenergize the low
demand mode solenoid valve when discharge pressure
reaches the set point This switch should be set approx-
imately 5 PSI above full load pressure with a 8-12 PSI
differential
Low Demand Mode Unloader Solenoid (Figure 1-4) - The
low demand mode solenoid valve when energized supplies
an air signal to close the blowdown valve. When de
energized it supplies an air signal to close compressor inlet
valve and exhausts air to open the blowdown valve
Pressure Regulator (Figure 1 -4) - The pressure regulator
must be set 25-30 PSIG to prevent inlet valve "slam".
Reservoir Pressure Switch (Figure 1 -4) - A pressure switch
is connected to the discharge manifold and wired to the
motor control circuit to prevent attempted starting of the
unit when there is more than 5 PSIG pressure in the oil
reservoir. This protects the unit from starting against load
when the oil reservoir has not had enough time to blow
down Blowdown time is usually about 45 seconds
, WARNING
Do not set the switch higher than 5 PSIG or render the
switch inoperative severe damage to the motor can
occur if started with pressure in the oil reservoir
Low Oil Pressure Shutdown (Figure 1 -4) - Units are
provided with a pressure switch piped to the compressor oil
sump and wired into the motor control circuit to protect the
unit against operation at too low an oil pressure and against
complete lubrication failure due to an oil line restriction or
sudden loss of oil pressure. The pressure switch is set 10-
15 PSIG and will stop the unit if the oil pressure falls below
this pressure any time during operation, and will prevent
the unit being started if the oil pressure does not rise to 10-
15 PSIG within 10 seconds of starting.
The pressure switch is set at 10-15 PSIG a the factory. If
resetting is necessary
HIGH DISCHARGE TEMPERATURE SWITCH CONDITION CHART
"A indicates Temperature Condition at Compressor Discharge.
"B' indicates Temperature Condition at Oil Separator.
"C indicates Probe Condition.
o
POWER
"A" o
"c o
0 \
"B
o
CONDITION
POWER ON "A "B'
"c"
POWER OFF
OFF
OFF OFF
OFF
NORMAL TEMPERATURE
RED RED RED OFF
COMPRESSOR HIGH TEMPERATURE
RED OFF
RED
OFF
SEPARATOR HIGH TEMPERATURE
RED
RED
OFF OFF
COMPRESSOR PROBE OPEN
RED OFF
RED
GREEN
SEPARATOR PROBE OPEN
RED
RED
OFF GREEN
COMPRESSOR PROBE SHORTED
RED OFF RED RED
SEPARATOR PROBE SHORTED
RED
RED
OFF
RED
COMPRESSOR PROBE SHORTED/
separator PROBE OPEN
RED
OFF OFF ORANGE
COMPRESSOR PROBE OPEN/
SEPARATOR PROBE SHORTED
RED
OFF OFF ORANGE
FIGURE 2-4
13-9-630 Section 4 Page 3