Technical Specifications​

Factory-fixed setpoint 55 mA. Supply 24 V AC/DC. Output SPDT relay, 1 A at 120 V AC and 2 A at 30 V DC. Output logic normally de-energized, changing state on ground-fault trip. Top terminal connections. Monitored circuit voltage up to 1500 V AC. Monitored frequency 50–400 Hz. Response time approximately 150 ms at 5% above setpoint. Auto-reset operation. Case flammability UL 94V-0. Operating temperature −15°C to +70°C. Relative humidity 0–95% non-condensing. Compliance UL 1053, CSA and CE.

Functional Features​

Zero-sequence window sensing for all phase and neutral conductors. Fixed 55 mA setpoint for repeatable ground-fault threshold. EMI and RFI immunity. Built-in test function. Automatic reset after fault clearance.

Application Scenarios​

Industrial automation panels. Power distribution monitoring. Medical electrical system grounding supervision. Process-control equipment ground-fault detection.

Performance Parameters​

55 mA trip setpoint. 150 ms response at 5% over setpoint. 1500 V AC monitored isolation rating. 1 A/120 V AC and 2 A/30 V DC relay rating.

Material Composition​

UL 94V-0 housing. Internal zero-sequence sensing element. Top-mounted terminal block with copper alloy contacts.

Structural Characteristics​

Window-type current sensor with all conductors passed through the sensing aperture. Integral relay output assembly. Top wiring terminals for power and alarm circuit.

Working Principle​

All phase and neutral conductors are routed through the sensor window. Under balanced conditions the vector sum of currents is zero. A ground fault creates residual current, and when this residual value exceeds the 55 mA setpoint the relay changes state and provides an alarm or control output.

Installation Requirements​

Route every current-carrying conductor of the monitored circuit through the sensor window. Use up to 14 AWG copper conductors for power and load wiring. Connect 24 V AC/DC from an isolated supply. For oversized conductors use an approved auxiliary current transformer. Mount on a clean, dry surface with access to the test button.

Usage Precautions​

Do not power the sensor from the same circuit that switches contactors or inductive loads. Verify system grounding before commissioning. Press the test button periodically to confirm relay operation. Never exceed the 1500 V AC monitored-circuit rating.