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Coreco LoP

Carel RTN400 controller — LOW voltage alarm

Source: Coreco_rtn400_instruction_sheet_9is24288-1_rel0413_en_termostatos.pdf

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What does Coreco LoP mean?

On the Coreco controller (Carel RTN400), LoP is lOW voltage alarm: voltage value read by the analog input is lower than the SPL value; display label LoP, alarm icon permanently on; regulation locked depending on SoU value.

Symptoms

  • Display shows LoP
  • Alarm icon permanently on
  • Regulation may lock depending on the SoU setting

Common causes

  • Supply/analog-input voltage outside the SPH/SPL limits
  • Unstable mains supply
  • Wiring or sensor issue on the analog input

Diagnostic steps

  1. 01

    Check the supply voltage

    LoP means the measured voltage is outside the configured SPH/SPL limits. Verify the actual supply against the limits.

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