ECA Meter Polarity Issue - Apportionment Calculation Error

This article covers an issue where the Electricity Consumption Apportionment (ECA) calculation does not recognise the electricity meter data because the meter input polarity is reversed.

Typical symptom: When running an Apportionment Calculation, the software reports that the electricity meter was not used during part or all of the selected period and that the calculation will be performed without electricity-meter data.

Error Message

The following warning may be displayed:

Electricity meter is not used during part or all of the specified period.
Calculation will be performed by a method not using data from the electricity meter.
Reference image: Insert the supplied Apportionment Calculation error screenshot here after uploading the image to Freshdesk.

Cause

The electricity-meter pulse wiring polarity may be reversed between the UTY-XWZXZF connection cable and the electricity meter.

The UTY-XWZXZF cable is connected to CN135 on the outdoor unit controller PCB. If the two meter-input conductors are connected with incorrect polarity, the outdoor unit may not correctly receive the meter pulses required for ECA calculation.

Corrective Action

  1. Confirm the electricity meter is connected to the outdoor unit using the UTY-XWZXZF external input cable.
  2. Locate the UTY-XWZXZF connection at CN135 on the outdoor unit controller PCB.
  3. Confirm the two conductors from CN135 to the electricity meter.
  4. Reverse the polarity of the two electricity-meter input wires.
  5. Restore the system and confirm that electricity-meter pulses are being received.
  6. Re-run the ECA / Apportionment Calculation and confirm the warning no longer appears.
Electrical safety: Isolate the equipment before altering wiring at the outdoor unit PCB. Confirm the correct terminals and wiring arrangement before restoring power.

CN135 Connection

The supplied reference photograph shows the two-wire UTY-XWZXZF meter cable connected at the outdoor unit controller PCB. If the ECA software does not detect meter usage, swap the two meter conductors to correct the input polarity.

Reference image: Insert the supplied CN135 / outdoor PCB photograph here after uploading the image to Freshdesk.

Electricity Meter Wiring

Confirm the wiring at the electricity meter as well as at the outdoor unit. The meter pulse-output conductors must maintain the correct polarity through to CN135.

Reference image: Insert the supplied electricity-meter panel photograph here after uploading the image to Freshdesk.

Verification

  • Confirm the electricity meter is powered and operating.
  • Confirm the meter pulse output is wired to the correct outdoor-unit input.
  • Confirm the UTY-XWZXZF cable is connected to CN135.
  • If the meter is not detected, reverse the two meter-input conductors.
  • Confirm meter data is being recorded before running a new apportionment period.
  • Re-run the Apportionment Calculation and confirm electricity-meter data is now included.