Specifications

140 Part Number STH12 9/10
MOVs Field Testing
Metal Oxide Varistors installed on the water and
carbonated water buttons on, McDonalds style
dispensing towers, are designed to completely absorb
electrical spikes keeping them out of the
microprocessor circuit eliminating complaints of:
• Not holding calibration
• Valves flowing by themselves
• Two valves coming on at the same time, etc.
Multiplex has designed a field test procedure that will
expose a faulty MOV. This procedure will also work on
the older style capacitors.
The field test procedure:
Depress separately both the water and soda water
button rapidly 5 - 6 times. While doing this, watch all
other valves. If you notice any dripping or any other
valve trying to energize, the MOVs need to be
replaced.
NOTE: Factory installed MOVs have heat shrink tubes
on each terminal leg. Always check to make sure that
heat shrink has not slipped down and is insulating the
MOV leg inside the terminal connector.
COM
NO
NC
MOV
Insulative
Tubing
BLK
GRN/WHT
RED