Overvoltage or Undervoltage Detected

What does 8496 mean?

The Safety PLC has detected an abnormal power supply condition, specifically either an overvoltage or undervoltage. This issue can stem from an unstable power source, incorrect wiring, or a fault within the PLC's internal power conditioning circuitry. Prolonged exposure to incorrect voltage can damage the PLC or cause erratic behavior, compromising safety.

Additional Steps

Steps 1–2 are listed in Priority Fix.

1. 3

   Measure the input power supply voltage at the PLC terminals to confirm it is within specified limits and stable.

2. 4

   Inspect power supply wiring and connections for looseness, damage, or corrosion.

3. 5

   If the error persists after power supply verification, replace the Safety PLC.