Protection Relay Testing Services in Pakistan.
TransfoLine provides precision Protection Relay Testing & Commissioning for industrial substations, captive power plants, and grid stations across Pakistan. Using industry-standard OMICRON CMC 256 and Megger 3-phase secondary injection test sets, our protection engineers calibrate, verify, and validate numerical, static, and electromechanical protective relays to guarantee fail-safe fault clearance and zero nuisance tripping.
What is Protection Relay Testing?
Protection relay testing is the precision testing of electrical protective relays by injecting simulated fault currents and system voltages to confirm that the relay correctly detects electrical faults (overcurrent, short-circuit, earth fault, reverse power, or differential unbalance) and signals the circuit breaker to trip within exact millisecond tolerances.
Secondary Injection Testing
Using 3-phase OMICRON CMC test sets, we inject calibrated currents and phase-shifted voltages directly into relay inputs to verify pickup thresholds, dropout ratios, reset times, and inverse definite minimum time (IDMT) operating curves.
Scheme & Trip Circuit Validation
We test the end-to-end trip scheme—from relay output contact actuation, through auxiliary tripping relays (Master Trip 86), up to the circuit breaker trip coil to ensure 100% reliable physical breaker opening.
ANSI Protection Functions We Test & Calibrate
Supported Numerical Relay Platforms
| Manufacturer | Supported Series | Key Applications | Testing Instrument |
|---|---|---|---|
| Schneider Electric | MiCOM P12x, P14x, P64x, Sepam 20/40/80 | Feeder, Transformer Differential, Motor | OMICRON CMC 256 |
| Siemens | SIPROTEC 4 & 5 (7SJ, 7UT, 7SA series) | Grid Substation Protection & Differential | OMICRON CMC 256 |
| ABB / Hitachi | Relion 615, 630, 670 series (REF, RET, REM) | Feeder, Transformer & Motor Management | OMICRON CMC 256 |
| SEL (Schweitzer) | SEL-751, SEL-787, SEL-300 series | Feeder Protection, Arc Flash Detection | OMICRON CMC 256 |
Frequently Asked Questions.
Expert answers regarding relay coordination and injection testing.
FREQUENCY How often should protection relays be tested?
Numerical relays should undergo secondary injection testing every 2 to 3 years. Electromechanical and static relays should be calibrated annually because spring tensions and internal electronic components drift over time.
COORDINATION Can TransfoLine help with relay coordination settings?
Yes. Our protection engineers perform full discrimination and relay coordination studies using ETAP/DigSILENT to calculate optimal pickup and time multiplier settings (TMS) before on-site injection testing.
Book Protection Relay Testing.
Our protection engineers deploy across Pakistan with calibrated OMICRON test sets.
Need secondary injection testing, nuisance trip investigation, or substation commissioning? Contact us directly.