American Dryer Corp. AD-200 Clothes Dryer User Manual


 
68
IMPORTANT: The L.E.D. indicator on the computer board that reads "DOOR" must be on in
order to successfully troubleshoot the following.
Theory of the Drive Circuit:
The incoming voltage L1, L2, and L3 are supplied to the power distribution block. Each line of this 3-phase
voltage is then fused with cartridge type fuses rated for the different incoming voltages. The voltage is then
supplied to the top half (L1,L2, and L3) of the reversing contactor. Providing the 24 A/C volts for the "DOOR"
input to the computer is present on pin #2 of the 15 pin computer harness the computer is going to output that 24
volts on pin #3 (forward) or pin #8 (reverse) of the pin computer connector.
Path of Voltage for the Drive Circuit:
Three phase voltage is applied to the power distribution block each line L1, L2, and L3 the voltage then
travels to the drive motor thermal magnetic overload. The voltage is then supplied to the reversing contactor
marked L1, L2, and L3. As long as the overload is not tripped 208-600 volts will always be here at the contactor.
When the computer calls for the forward motion of the basket, 24 A/C volts will output of pin #3 of the computer.
This 24 A/C volts will pass through it and J1 and J3 connectors pin #3 on both, and travel to the forward coil of
reversing contactor, the contactor will be marked A1. The other side of the coil A2 will be directly grounded.
When the 24 A/C volts reaches the coil, the contactor closes and the incoming voltage that is supplied to the top
of the contactor L1, L2, and L3 meets the T1, T2, and T3 of the contactor which then travels down to the soft
start via the drive motor. The reversing action is projected the same way as the forward with the exception of the
24 A/C volts will output from the computer through pin #8, and the connectors in the path of voltage are still J1
and J3 but now pin #8 on both.