2)Auxiliary Contact Block

The Auxiliary Contact Block is mounted on the side of the overload. Its function is to sense an overload trip, thereby triggering a safety fault which will disable the drying cycle. An “Overload Fault” message will appear on the light emitting diode (L.E.D.) display on the Phase 7 microprocessor controller (computer).

a)Auxiliary Contact Block Replacement

(1)Discontinue electrical power to the dryer.

(2)Remove the Thermal Magnetic Starter (TMS) from the din rail by pulling the tab on the bottom of the contact block and lifting upward.

(3)Remove the two (2) wires going to the auxiliary contact block and label for correct reinstallation.

(4)There are two (2) types of auxiliary contact blocks...one with a screw and the other with a clip...

To remove the style with the screw from the thermal magnetic starter simply remove the screw.

To remove the style with a clip simply push in the clip and remove.

(5)To install new auxiliary contact block, reverse above procedure (Step #4 thru Step #1).

3)Varistor (Metal Oxide Varistor [MOV])

The Varistor is used to suppress any inductive electrical spikes produced by the energizing and collapsing of the coil voltage.

a)Varistor Replacement

(1)Discontinue electrical power to the dryer.

(2)Loosen the screws marked A1 and A2 on the contactor.

(3)Remove the varistor.

(4)Verify that no additional wires were inadvertently removed.

(5)Reverse procedure to install new varistor.

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American Dryer Corp AD-310 Phase 7 service manual