Power Soak 37179 PS-275 Service Manual - Manual (Page 42)

36
8.3 Sensor Pad
8.3a Disassembly - To access the contents of the Sensor Pad, unbolt the mounting
bracket that holds the sensor pad and remove the sensor pad from the back side of the
wash tank. Lift the retainer plate out of the rubber pad and then remove the electrical
components.
8.3b Inspection
– Examine the wires for damage to the insulation. Test each of the
components for proper function. Unplug the spade connectors from the tabs on the
thermo-disc and use an Ohm meter to measure the resistance across the tabs of the
thermo-disc. If this measurement shows more than one ohm of resistance it will keep
the UPM from operating correctly. Individually check each tab connection for continuity
to the mounting flange. Continuity to the flange would indicate a defective thermo-disc
that will need to be replaced. Check the operation of the Thermistor as described in
section 7.5.
8.3c Assembly – Place the components back into the rubber pad and secure them in
place with the retainer plate. It is very important to use heat sink compound on the side
of the thermo-disc and thermistor that will be placed against the surface of the tank to
ensure good heat transfer. Slide the pad assembly back into the mounting bracket and
bolt the bracket to the side of the wash tank.
8.4 Chemical Dispenser (Optional)
A chemical dispenser can be purchased from Power Soak. The dispenser
that is purchased from Power Soak will be mounted under the drain board
on the “clean side” of the sink assembly and contain two or three pumps,
depending on the application. The wiring harness has connections to
supply power and operating signals to the chemical dispenser pumps.
Malfunctions in the chemical dispenser can lower the operating voltage of
the PS-275 to levels that are unacceptable and will cause problems with
the operation of the PS-275 control system. See the chemical dispenser
literature for more information on the operation and service of the
dispenser.
The sensor pad is located on
the back side of the wash tank Sensor pad removed from wash tank.
Thermo-disc
Heat sink
compound
is used on
these faces
Retainer plate
Thermistor