Section Vii - Service Adjustments; Pressure Switch - Quincy Compressor QSD 65040-AB Instruction Manual

Section VII - Service Adjustments

• Pressure Switch

WARNING
!
Never adjust the pressure higher than the factory
setting. Death, serious injury and compressor or
property damage could result.
Pressure Switch (Back-up Operating Mode)
The PS1 pressure switch will determine at what pressure
the compressor will load and unload. The range
adjustment is made by turning the adjustment to increase
the cut-in /cut-out pressure and to lower the cut-in/cut-out
pressure on PS1. Never exceed the maximum factory
pressure rating.
NOTE
See Section VIII - Power$ync II
electronic control operation of this unit.
CAUTION
!
Before returning compressor to service in Back-
up Mode, check for possible component failure.
Certain mechanical failures can be mistaken as a
microprocessor failure. Continued operation
with faulty components may void warranty.
30
Adjusting Pressure Switch
The following procedure should be used for maximum
safety when preparing for maintenance or service:
1) Disconnect and lockout the main power switch and
2) Close shut-off valve (block valve) between the
3) Open the manual shut-off valve and wait for the
4) Shut off water and depressurize system if water-
5) Remove supply tube going to pressure switch.
6) Connect regulated source of air with calibrated
7) Set pressure supply at trip point of pressure switch.
8) Adjust switch to trip at trip point.
9) PS2, PS3, and PS4 are not adjustable. Verify
™ Operation for
PS1 Desired unload pressure (adjustable)
PS2 Interstage 23 PSI (fixed)
PS3 Stage 2 discharge 23 PSI (fixed)
PS4 Fluid 15 PSI (fixed)
Quincy Compressor
hang a sign at the switch of the unit being serviced.
compressor and plant air system to prevent any back
flow of air into the compressor. Never depend upon
a check valve to isolate the system.
pressure in the compressor to be completely relieved
before starting service. Do not close the manual vent
valve at any time while servicing.
cooled.
gauge.
settings are correct per steps 1 through 7.
®
- QSD™