E-Stop Discrepancy Error - Input Group 4
Beckhoff · TwinSAFE Logic FB
¿Qué significa FB ESTOP Bit 3 ?
A discrepancy has been detected between the two channels of input group 4 for the FB ESTOP. This indicates that the redundant E-Stop input signals are not in agreement, suggesting a potential failure of one channel, a wiring issue, or an incorrect switching sequence. This will prevent the E-Stop function from operating safely and halt the machine.
Causas comunes
- A wiring fault (e.g., open circuit or short to ground) on one channel of the E-Stop input for Group 4.
- Mechanical binding or debris preventing one side of the E-Stop button's redundant contacts from operating freely.
- High resistance in one of the cable conductors supplying the E-Stop input, causing a voltage difference across channels.
- Input filtering parameters (e.g., P_INPUT_FILTER_G4) set too aggressively, ignoring legitimate input changes.
- Faulty E-Stop switch, where one redundant contact is intermittently failing to make proper connection.
Pasos de reparación & Lista de verificación
Haga clic en los pasos para seguir su progreso.
- 1
De-energize and check the resistance of both redundant E-Stop input lines from the device to the controller (e.g., from E-Stop button to terminals X4.1 and X4.2).
- 2
Verify the physical operation of the E-Stop button for Input Group 4, ensuring both contacts actuate smoothly and simultaneously.
- 3
Measure the voltage level on both E-Stop input channels at the safety controller during both active and inactive states.
- 4
Inspect all connections for Input Group 4, ensuring terminal screws are tightened to specified torque and no corrosion is present.
- 5
Temporarily increase the discrepancy time parameter (e.g., P_DISC_TIME_G4) in the safety controller to rule out rapid asynchronous switching as the cause.