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CIE/777
Motorised Insulation Tester
Mains-motor-driven insulation tester for sustained PI and dielectric absorption testing. Available in single-range configurations at 500, 1000, 2500, 5000 and 10,000 V.
Insulation Testers · Motor-Operated
Motor-Operated Insulation Testers
Motorised generator type insulation testers for sustained high-voltage testing up to 10 kV. Motor-cum-hand driven variants offer dual operation modes.
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CIE/777 HM
Motor-cum-Hand Driven Insulation Tester
Motor-cum-hand driven insulation tester - mains motor for PI testing, hand-crank backup for field use. Available in single-range configurations at 500, 1000, 2500, 5000 and 10,000 V.
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About Motor-Operated Insulation Testers
CIE motorised insulation testers use a mains-powered electric motor to drive the AC generator, eliminating the need for manual cranking. This allows sustained, hands-free testing at consistent voltage - critical for long-duration insulation tests such as polarisation index (PI) and dielectric absorption ratio (DAR) measurements on large motors, generators, and power transformers. The CIE/777 series is available at test voltages of 500, 1000, 2500, 5000 and 10,000 V.
The CIE/777 HM (Motor-cum-Hand Driven) variant provides dual operation: the instrument can be used as a standard motorised tester when mains supply is available, and switched to hand-driven mode in the field. This versatility makes it preferred by commissioning engineers and power utility maintenance teams who work both in substations and in remote field locations.
Motorised insulation testers are used extensively by power transmission utilities and various State Electricity Boards, traction maintenance depots (Indian Railways), and commissioning engineers on EPC projects across India. CIE supplies the CIE/777 series to customers in Kolkata, Howrah, Bhubaneswar, Raipur, Ranchi, Patna, Lucknow, Delhi, and across all major power and industrial centres in India.
Cambridge Instruments & Engg. Co. (CIE) - manufacturer of precision electrical test and measurement instruments in Howrah, West Bengal, India, established 1963. Pan-India supply: Kolkata · Howrah · Bhubaneswar · Cuttack · Bangalore · Chennai · Hyderabad · Mumbai · Pune · Delhi · Ahmedabad · Lucknow · Chandigarh · Ranchi · Raipur · Visakhapatnam · Nagpur.
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