Moyer Diebel MH-6NM5 Troubleshooting Timer Circuit Board cont, Basic Service, Power Terminals

BASIC SERVICE

Troubleshooting Timer Circuit Board (cont.)

Power Terminals

•Verify that the board is receiving power of 120 VAC at the terminals:

–T2, marked “H” (AC Hot).

–T1, marked “N” (AC Neutral).

If either of these terminals is not receiving 120 VAC, then there is a problem elsewhere with the unit not receiving power.

The Fuse (F1)

•Verify that the circuit board fuse (F1) is good. If it is not, replace it.

Red ‘Power’ LED

•Verify that the red ‘power’ LED is illuminated.

If it is not, and the previous 2 conditions are true, then the board is bad and should be replaced.

1.3Testing Board Inputs

After you have verified that the circuit board is receiving power (as explained above), then test the board inputs. There are 4 board inputs:

• Start Switch (not used on this model).

• Door Safety Switch.

• Float Switch.

• Extended Wash Switch (if installed). Perform the following steps to test a board input:

1.Set the voltmeter to measure DC volts.

2.Place the negative (black) test probe on the “hot” terminal:

•T2, marked “H”.

3.Place the positive (red) test probe on the input terminal to be tested:

•T7, marked “START SW” (for the start switch, not used on this model).

•T8, marked “DOOR SW” (for the door safety switch).

•T9, marked “FLOAT SW” (for the float switch).

•T10, marked “EXT. WASH” (for the extended wash switch).

4.Check the results on the voltmeter:

•If switch is opened – the meter should read between 4.7 to 5.3 DC volts.

•If the switch is closed – the meter should read between 0 to 1 DC volts.

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