On-Load & De-Energised Tap-Changers (OLTC/DETC)
Standards: IEC 60214
Ratio regulation under load or off-circuit, vacuum/oil diverter options, motor drives and replacement gears.
Vacuum OLTC
Low-maintenance on-load tap-changers with vacuum interrupters for power transformers.
Oil Diverter OLTC
Conventional high-capacity on-load tap-changers.
Off-Circuit Tap Changers (DETC)
De-energised ratio selectors for distribution and industrial transformers.
Motor Drive Units (MDU)
Electronic/mechanical drive units for remote tap control.
OLTC Oil Filter Units
Keeps diverter oil clean, extends maintenance intervals.
Frequently asked
An on-load tap-changer (OLTC) changes the tap position under load without interrupting supply; a de-energised tap-changer (DETC) only changes ratio off-circuit.
It steps the transformer turns ratio up or down to hold the secondary voltage within limits as the load and system voltage vary.
Contact and diverter wear — often detected by acetylene in the oil, which is why OLTC oil tests and condition monitoring are routine.
Post an RFQ to reach relevant manufacturers and suppliers.
Request an RFQ Supply this? Claim your company →Directory entries are compiled from public sources and, where applicable, confirmed by the company. Verification confirms stated credentials — it is not a guarantee of quality or performance.