Bin Switch Fails Open; Bin Switch Fails Closed; Continuity Test - Manitowoc S300 Technician's Handbook

SYMPTOMS

Bin Switch Fails Open

• The ice machine will not start with the toggle
switch in the ice position, but runs normally with
the toggle switch in the clean position.

Bin Switch Fails Closed

• Safety limit 2 is recorded in the control board
memory and the harvest cycle continues after the
ice opens and closes the water curtain/ice
dampers (harvest cycle is 3.5 minutes for single
evaporators and 7 minutes for Quad evaporator
models).
DIAGNOSTIC AIDS:
• Always use the water curtain/ice dampers magnet
to cycle the switch (a larger or smaller magnet will
affect switch operation).
• Readings are affected by your test lead connection
and VOM battery strength. Verify you have solid
connections and a correctly functioning VOM
before testing bin switch.
• Open the curtain/ice dampers for 3 seconds, then
close the curtain/ice dampers for 3 seconds. This
will allow your VOM display to settle.
• With the bin switch closed your meter reading
should be 0 (0 to 10 is acceptable). With the
curtain/ice dampers open the reading must be
infinity (OL).

CONTINUITY TEST

1. Disconnect the bin switch wires to isolate the bin
switch from the control board.
2. Connect an ohmmeter to the disconnected bin
switch wires.
3. Cycle the bin switch open and closed 25 times by
opening and closing the water curtain/ice
dampers. Watch for consistent readings each time
the bin switch is cycled open and closed (bin
switch failure could be erratic).
138 Part Number 80-1479-3 7/10