Wiring of Relay Protection Tester

Wiring a relay protection tester involves connecting the voltage and current output terminals to the corresponding relay inputs, ensuring proper color coding, grounding, and phase alignment.

Preparation and Safety

Before wiring, ensure the tester is connected to a 220V AC power supply and is reliably grounded to prevent electric shock ( ). Disconnect the power supply of the relay protection device before starting, and wear appropriate insulated gloves and safety gear ( ).

Terminal Connections

Identify terminals: Most relay protection testers have yellow, green, red, and black voltage output terminals on the front panel, and DC output, power, and grounding jacks on the back ( ). Color-coded wiring: Match the coil color of the relay to the corresponding tester terminal. For example, connect the black coil to the black current output terminal, and the other end to the relay ( ).

Grounding: Connect the tester's grounding jack to the relay system's ground to ensure safety and accurate measurements ( ).

Phase and Compensation Current Wiring

For single-phase tests, connect the tester current output directly to the relay phase; no phase adjustment is needed ( ). For three-phase transformers, wiring depends on the transformer type: Y/Y (Y0) transformers: Connect tester IA to the high-voltage phase A, IB to the low-voltage phase a, and short-circuit the neutral lines to the tester IN ( ). Y/?-11 transformers: Use IA, IB, and IC for the high- and low-voltage phases, with IC serving as the compensation current.

Ensure the currents on the low-voltage side are in reverse phase relative to the high-voltage side ( ). Always verify the phase angles: for example, when testing phase A, set IA to 0°, IB to 180°, and IC to 0° ( ).

Verification

After wiring, use a multimeter to check continuity and confirm that all connections are correct ( ). Ensure that voltage circuits are not short-circuited and that the current circuit load matches the tester's technical specifications ( ).

Final Steps

Once wiring is verified: Set the test parameters (current amplitude, phase, step size) according to the relay and transformer specifications ( ). Select manual or automatic test mode and start the test. Monitor the relay response and record the action time or other test results ( ).

Following these steps ensures safe and accurate operation of the relay protection tester while preventing damage to the relay or tester.