Utitlity Test Solutions

Live Hv Ct Tester: Model 590f

For customers who cannot be disconnected or offline when performing metering CT tests, the 590F1 or F3 HV (High Voltage) accessory can be added as a retrofit kit to our popular 590G and 590GV2 CT testers.

The first part of the kit is the clamp on CT unit which is mounted on the end of a hot stick. This unit has a battery powered electronic compensation circuit for the clamp on CT ("clip on") which greatly improves accuracy over a wide operating range, typically 5A to 1450A.

The 590G-V2 has all the features and advantages of the previous models with additional testing features, better accuracy and smaller size and weight.A microprocessor is also used to control the clip on compensation, manage the internal range changing and provide communications via a fibre optic and RS-485 interface.

The fibre optic cable runs between the 590F1 and a small interface unit at the base of the hotstick. From there the signal is transmitted through a 100M drum of RS485 cable to the 590C/G or G-V2 CT tester.

The combination of hot stick and cable has been tested to 100kV, line to ground. The actual breakdown voltage of the hotstick and fibre optic cable is much greater than 100kV, but for operator safety we suggest not using this test set above 100kV. However, with a longer hotstick and suitable precautions the 590F1 or F3 unit can be used at higher voltages.

The CT primary current measured by the clipon is sent via the cable to the 590G or G-V2 CT Tester which can be up to 100M away. Extra drums can be daisy chained up to 400M in total. The 590C/G or G-V2 unit measures the CT secondary current, 5A, 1A or lower, and then calculates the CT ratio and phase error to an accuracy of 0.1%.

For testing live LV Low Voltage or low current CTs, we have a variety of electronically compensated clamp on CT's, "Clip ons". Let us know what you require and we can adapt the 590F to suit.

We have two regular low to medium voltage clip ons. One is for cables carrying up to 1,000A and the other is a large jaw clip on for busbars up to 2,500A.