Two-Hand Discrepancy Error - Between Pairs
Beckhoff · TwinSAFE Logic FB
Was bedeutet FB TWOHAND Bit 2 ?
A discrepancy has been detected between the actuation times of input pair 1 and input pair 2 for the FB TWOHAND. This means the operator is not actuating both hands simultaneously within the allowed time window, or there's an issue with the timing of the two-hand control device itself. This fault ensures true simultaneous actuation for safety and stops the machine.
Häufige Ursachen
- Operator actuation technique: one hand consistently actuates significantly before the other hand.
- Mechanical binding or slow response of one two-hand button assembly compared to the other.
- Excessive discrepancy time configured between input pairs (e.g., P_BetweenPairDiscTime) is too short for the application or operator.
- Voltage drop or intermittent connection affecting the response time of one entire input pair.
- Slight variation in switch bounce characteristics between the two separate input pair buttons.
Reparaturschritte & Checkliste
Klicken Sie auf Schritte, um Ihren Fortschritt zu verfolgen.
- 1
1. Observe the operator's hand placement and simultaneous actuation technique, providing retraining if necessary to ensure both buttons are pressed concurrently.
- 2
2. Measure the actuation and release times of each two-hand button assembly using a timing device or oscilloscope connected to the input terminals (e.g., X5.1 and X5.3).
- 3
3. Access the safety controller's programming interface and adjust the 'BetweenPairDiscTime' parameter (e.g., increase from 200ms to 350ms) to accommodate operator variance.
- 4
4. Verify the integrity of the 24VDC supply voltage to both two-hand button assemblies, checking for drops below 22VDC during actuation.
- 5
5. Check and clean the electrical contacts within both two-hand button assemblies for any foreign material that could impede consistent response.