Diag 2 Flash 5

Field Voltage Too Low

Beckhoff · EL2904 TwinSAFE Fail-Safe Output Terminal

What does Diag 2 Flash 5 mean?

The voltage supplied to the power contacts of the terminal is below the permissible operating range (24V -15%/+20%). This can be caused by the voltage not being switched on, being switched on after the terminal supply, being generally too low, or by a short-circuit at an output causing a voltage drop. This affects the overall operation of the terminal's outputs and can lead to unreliable behavior or shutdown of safety functions.

Complete Troubleshooting Guide

  1. 1

    Switch on the voltage at the power contacts and reset the error display through a PowerOn Reset of the terminal.

  2. 2

    Ensure the voltage at the power contacts is switched on before or simultaneously with the terminal supply, then reset the error display via PowerOn Reset.

  3. 3

    Increase the voltage at the power contacts to within the specified range and reset the error display through PowerOn Reset.

  4. 4

    Eliminate any short-circuits at the outputs and check supply lines for excessive voltage drops, designing the power supply accordingly.

  5. 5

    Take suitable EMC measures if electromagnetic interference is suspected to be contributing to voltage instability. If the issue persists, replace the terminal.