Pressure Switch Adjustment - Quincy Compressor Industrial Series Instruction Manual

POCKET CLIP
SLIDING
RUBBER O-RINGS
DEFLECTION
FORCE SCALE
(READ DOWN)
DEFLECTION
DISTANCE
SCALE
(READ UP)
Belt Tension Gauge
Fig. 5-2
PRESSURE
ADJUSTMENT
SCREW
Fig. 5-3 Pressure Switch
WARNING !
Industrial / Air Master Series
50161-105, March 2008
Pix 1153
ELECTRICAL
CONTACTS
Pix 1067
to increase the amount of air pressure required to open the switch
and stop the unit. Screw the spring loaded adjustment screw out
(counterclockwise) to decrease the amount of air pressure required
to open the switch and stop the unit.
Standard pressure switches supplied by Quincy Compressor are equipped
with a fixed 20 PSIG (approx.) differential. Optional switches include both
pressure and differential adjustment capabilities.
Electric power always exists inside the pressure switch whenever
the compressor package is connected to a power supply. Be careful
not to touch any electrical leads when adjusting the pressure
switch.
30
Step 2) Determine the amount of deflection (
in inches) required to measure deflection force (in
pounds) by multiplying the span length x
(i.e. 32" span length x 1
tion required to measure deflection force).
Step 3) Lay a straightedge across the top outer
surface of a drive belt from pulley to sheave.
Step 4) At the center of the span, perpendicu-
lar to the belt, apply pressure to the outer surface
of the belt with a belt tension gauge (refer to Fig.
5-2, Belt Tension Gauge). Force the belt to the
predetermined deflection (refer to Step 2 above).
Record the reading on the belt tension gauge and
compare to the chart following Fig 5-1. The de-
flection force reading should be within the mini-
mum and maximum values shown. Adjust belt(s)
accordingly. New belts should be initially tensioned
to the maximum value plus 33% (multiply by 1.33).
Step 5) Recheck the tension of the new belts
several times in the first 50 hours of operation and
adjust if necessary. Thereafter, check belt tension
on a regular basis (refer to SECTION 5, Mainte-
nance Schedule).

Pressure Switch Adjustment

Pressure switches provided by Quincy Compres-
sor are pre-set at the factory and usually do not
require adjustment. However, the following pro-
cedures can be performed by a qualified electri-
cian to adjust the pressure switch.
Step 1) Remove the pressure switch cover.
Step 2) While the compressor is running, screw
the spring loaded adjustment screw in (clockwise)
3501 Wismann Lane, Quincy Ill. - 62305-3116
1 / (.016)
64
/ [.016] = 1 / "[.50] of deflec-
64 2
Quincy Compressor