Oil Test Sets — CIE/7000 Series

Transformer oil dielectric strength testing (breakdown voltage or BDV testing) is a mandatory quality check performed on transformer oil before filling a new transformer, after filtering or processing used oil, and as part of routine transformer maintenance. The dielectric strength of the oil (measured in kV) indicates its ability to withstand electrical stress without breaking down — a critical parameter for transformer reliability and life.

CIE manufactures the 7000 series of transformer oil BDV testers in three voltage ratings: CIE/7050 (50 kV), CIE/7100 (100 kV), and CIE/7120 (120 kV). Each instrument is supplied with a standard test vessel conforming to IS 6792 / IEC 60156, with centre-point grounded electrodes. Manual and motorised (automatic) variants are available — the motorised variants perform the full test cycle automatically and are preferred in laboratories processing large volumes of oil samples.

Transformer oil test sets are used by power utilities (PGCIL, WBSETCL, state transcos and discoms), transformer manufacturers, oil processing companies, testing laboratories, and large industrial consumers with HV transformers. CIE supplies oil BDV testers across India — Kolkata, Howrah, Bhubaneswar, Bangalore, Chennai, Hyderabad, Mumbai, Delhi, Pune, Ahmedabad, Raipur, Ranchi, and all locations where power and distribution transformers are installed and maintained.