Phase Monitor - Trane SYMBIO 700 Troubleshooting Manual

Phase Monitor

Phase monitors are installed on all 5 to 25 ton products with three-phase power.
The main purpose of the phase monitor is to ensure that the scroll compressors are rotating in the
proper direction.
A green LED on the phase monitor indicates proper phasing.
If the input leads are crossed, the phase monitor will sense this and will immediately shut the unit down.
The monitor will illuminate a red LED indicating a phase reversal condition.
If the control wires are crossed on the Y and Y-out terminals on the phase monitor, this will also cause
the red LED to illuminate and will not allow the unit to run.
If a red LED is displayed, swap two leads on the incoming power to the unit. If the red LED is still
illuminated, check for proper control wiring connections to the phase monitor.
If all wiring is correct, the phase monitor is defective and needs to be replaced.
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