MHC-1 Service Manual
3
SEQUENCE OF OPERATIONS
Power Supply
Electrical power is supplied to the unit by a 3
conductor service for single phase.
120VAC
Black conductor is hot.
White conductor is neutral.
Green and yellow conductor is ground.
Power is permanently supplied to the main power
switch.
Heating Circuit
Closing the main power switch supplies voltage to the
power board and control board. The control is set to
the desired temperature.
The control then intermittently supplies 120VAC
through the power board to the heater plates.
Temperature is then controlled by the two temperature
sensors sending a reference signal back to the control
board.
