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Electrical Operation (Gas Dryers Models With Electronic Moisture Sensor)
Note:
Always refer to the wiring diagram or schematic with the product.
Sample wiring diagram for models with electronic moisture sensor
Auto Dry Regular Cycle
When the dryer is connected to electrical power, line 1
is connected to terminal B of the timer and one side of
the drum light. When the timer is set to the Auto Dry
cycle, contacts B to C and B to A are closed. This
provides power at the start of the cycle to four circuits:
the drive motor circuit, timer motor circuit, electronic
moisture sensor circuit and the heating circuit.
Drive Motor Circuit:
When contacts B to C are closed line 1 is applied to
terminal M4 of the drive motor. Terminal M4 is con-
nected in the motor to one side of the thermal over-
load. (The thermal overload protects the motor from
being damaged by overheating.) The other side of the
thermal overload is connected to both the run winding
and the start winding of the drive motor. When the
motor is not turning, the other end of the start winding
is connected internally to terminal M5 of the motor,
through the NC contact of the motor centrifugal switch.
The other end of the run winding is also connected inter-
nally to terminal M5.
When the motor is not turning, the start winding and the
run winding are connected in parallel. Terminal M5 of
the motor is connected to the start switch, which is con-
nected to neutral through the door switch. When the
start switch is activated and the dryer door closed, line 1
to neutral voltage is applied across both the start and
run windings of the drive motor. With power applied to
both the start and run windings, the motor starts to turn.
When the speed of the motor reaches about 80% of its
normal run speed, the contacts of the centrifugal switch
change from NC to NO, opening the circuit to the start
winding and connecting the run winding to motor ter-
minal M6. Terminal M6 is connected to neutral through
the door switch. The start winding is now out of the
circuit and the run winding circuit is bypassing the start
switch so the switch can be released without interrupt-
ing power to the run winding.
The drive motor performs two tasks in the dryer. A
pulley attached to one end of the motor shaft uses a
belt to drive the dryer drum. The blower wheel, at-
tached to the other end of the motor shaft, pulls the air
through the clothes and forces it out the exhaust vent.
