GE Monogram ZBD6400 Series Technical Service Manual page 30

6000 & 7000 Series DISHWASHERS
4.11.2 Overfill Mode - Drain Pump Not Operating
Symptom: Overfill mode indicated by Heated Dry or Smart
Dry LED rapidly flashing, all outputs terminated and the Drain
Pump NOT operating.
The electronic Power Control Board continuously monitors
the complete drain and Drain Pump circuit from the DRAIN
tab terminal to the N terminal on the Mains Terminal Block. In
effect the "watch dog circuit", ensures if an open circuit is
present as a 120 V AC neutral, the Heated Dry or Smart Dry
LED will rapidly flash to indicate an overfill. All outputs from
the electronic Power Control Board will be terminated.
The complete 120 V AC neutral circuit with the Drain Pump
field windings of DC resistance 35 ohms, must provide
continuity from the electronic Power Control Board tab termi-
nal DRAIN to the neutral N terminal of the Mains Terminal
Block.
Refer to the following "Neutral" watch dog wiring circuit for
drain mode.
Circuit Diagram: Neutral "Watch Dog" circuit for drain mode
Important. Check all wiring connections before reconnecting to supply.
The following malfunctions can cause the 'Heated D ry' or
'Smart Dry' LED to rapidly flash and terminate all outputs
of the electronic Power Control Board.
• DRAIN tab terminal not attached to the electronic Power
Control Board.
• Active cable not attached to Drain Pump tab terminal.
• Terminals at plug TB2-3 not connected.
• Open circuit of drain pump field windings - resistance 35ý
± 10% must be present.
• Neutral cable not attached to drain pump tab terminal.
• Neutral cable not connected to terminal of mains terminal
block.
• Any faulty quick connect terminals in the neutral circuit.
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