A mis-set relay turns a local fault into a plant-wide blackout. We verify every stage of your protection chain.
Numerical & electromechanical relay testing
Secondary injection test kits
CT / PT ratio & polarity verification
Protection coordination study
Trip-circuit & interlock verification
Fault-record analysisAt Tajalli Tech, we provide comprehensive secondary injection and relay testing, designed to confirm that each protection relay operates correctly and that the wider protection scheme is properly coordinated. Our engineers inject calibrated secondary current and voltage into every relay, whether numerical or electromechanical, to verify the pickup, drop-off and time-current characteristics, and confirm CT and PT ratio and polarity so that each relay receives an accurate signal. We also undertake discrimination and coordination studies to ensure the device nearest a fault operates first, work carried out in accordance with IEC 60255 and IS 13234 and applied on projects including relay coordination for a 10 MW plant at Hardoi.
On completion, you receive a detailed per-relay report documenting the injection results, including measured pickup, operating time at test multiples of setting and drop-off, together with verified CT and PT ratio and polarity, proven trip circuits and a discrimination check confirming that the nearest device clears first. The report is prepared in accordance with applicable IS/IEC standards and includes a marked-up set of coordination curves for your records.
Yes. We test modern numerical relays and older electromechanical relays alike, injecting into each device to read its actual operating characteristic. Our engineers undertake this work across Lucknow, throughout Uttar Pradesh and pan-India.
Yes. We plot the complete protection chain, grade the time and current settings so that a local fault trips the nearest device first, and confirm the result by injection rather than relying on calculation alone.
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