If the manual test shows normal conductivity, check if the actuator block is worn or displaced, which may prevent the switch roller from being pressed down. Adjust the position of the stopper or replace worn parts.
Check wiring: There should be a 24V voltage between the COM and NO terminals when measuring the voltage range of the multimeter (when the switch is not pressed down). If the voltage is 0, check for broken upstream fuses, power modules, or cables.
Check the PLC input module channel: short-circuit the input point to 0V or 24V (depending on the type), and confirm if the module is functioning properly. If normal, replace the limit switch.
7.2 Fault phenomenon: intermittent false triggering, occasional no signal
Reason: Loose wiring and vibration caused the wire to instantly disconnect. Reconnect the terminals and apply thread locking adhesive.
Reason: The internal contact spring of the switch is fatigued, and the action point drifts. Replace the switch with a new one.
Reason: There is interference from high-power frequency converters or electromagnets nearby. Although mechanical contacts are not directly affected by EMI, long-term induction may cause subsequent electronic devices to malfunction. Suggest using shielded cables and grounding the shielding layer at one end.
7.3 Fault phenomenon: The switch remains conductive (normally closed)
Mechanical jamming: The actuator is stuck by foreign objects or cannot rebound at the overtravel position. Remove obstacles and check if the spring is corroded.
Contact welding: overcurrent occurs (load current exceeds 0.4 A or no arc extinguishing circuit is added). Replace the switch and add an intermediate relay in the circuit.
Comparison Table for Production Shutdown and Replacement Selection
When the GIV50-11 prototype number cannot be found on the market, the following parameter matching logic can be used to select a substitute:
Recommended model series for replacing original switch parameters (example)
24V DC, 0.4A, NO voltage and current ≥ 0.4A, NO contact, mechanical action Omron D4N-1120 (roller plunger type)
Cylindrical thread M20 × 1.5 installation thread consistent with Schneider XCMD2110L1
Metal casing, IP65 protection level not lower than the original switch Turck BNS 819-D
Maximum temperature 50 ℃ Operating temperature -25~70 ℃ Baruff BNS 819-BL
Precautions for renovation:
The installation hole spacing may vary for different brands, and it is necessary to process adapter plates or enlarge holes.
The actuator type (roller, plunger, rod type) needs to match the original machine action mode. GIV50-11 does not specify the actuator type, but from the picture it appears to be a short cylinder, possibly a plunger or roller lever type. Please confirm before replacing.
If the original circuit requires normally closed (NC) logic, a 24V DC intermediate relay can be installed after GIV50-11 to convert the NO contact to NC.
Safety compliance and final recommendations
GIV50-11 limit switch should be used in accordance with IEC 60947-5-1 standard. In safety related applications (such as emergency stop limit), a positive opening structure must be used to ensure that even if the contact is welded, it can be forcibly disconnected under mechanical action. After checking the manual, it was not clear whether the switch has a forced disconnection function. Therefore, it is not recommended to use it as a safety limit (such as the upper limit of a crane) and can only be used for general position detection.
To extend the service life, please avoid directly driving large inductive loads in the control circuit. For a contact capacity of 0.4 A, it is recommended to drive the PLC input module (usually 5-20 mA) or micro relay (coil current<30 mA).
