Two-Hand Discrepancy Error - Pair 1 (Safe Inputs Active)

What does FB TWOHAND Bit 8 mean?

Similar to 'FB TWOHAND Bit 0', but specifically when the 'Safe Inputs after Disc Error' option is active for input pair 1. This means a discrepancy occurred, and although the FB is attempting to maintain a safe state for the inputs, the error persists, indicating a critical issue with the input pair that requires immediate attention and prevents operation.

• Wiring short-circuit or open-circuit on channel 1 or 2 of input pair 1 (e.g., terminals X4.1, X4.2).
• Degraded or faulty contacts within the two-hand control button for input pair 1.
• Intermittent power supply to the input pair 1 buttons, causing erratic signal detection.
• Electromagnetic interference (EMI) causing transient false signals on input pair 1's wiring.
• Safety input module hardware fault affecting the reading of input pair 1 signals.

Click steps to track your progress.

1. 1

   1. Power down the safety system, then perform a continuity test on the wiring from the two-hand buttons of input pair 1 to their respective safety input terminals (e.g., X4.1, X4.2).

2. 2

   2. With power restored, actuate the buttons for input pair 1 and monitor the diagnostic LEDs for consistent switching on the safety module.

3. 3

   3. Measure the 24VDC supply voltage at the two-hand buttons for input pair 1, ensuring it remains stable at 24VDC +/-10%.

4. 4

   4. Replace the two-hand button assembly for input pair 1 if it exhibits inconsistent contact closure or release during repeated actuation.

5. 5

   5. Initiate a safety reset sequence (e.g., via a dedicated reset button or HMI command) after clearing the root cause to re-enable the FB TWOHAND function.