KR-3400AIntroduction to Series Main Transformer Protection and Measurement Devices

The KR-3000A series main transformer protection and measurement device is a complete set of protection devices suitable for transformers with three or more turns and voltage levels of 110KV and above. The complete set of protection consists of differential protection, backup protection, and non electricity protection. For a 110KV transformer, generally KR-3420A (differential protection)+KR-3410A (high-voltage side backup protection measurement and control)+KR-3430A (low-voltage side backup protection measurement and control)+KR3440A (non electricity protection+operation circuit) can be used to form all the protection and measurement functions of the transformer. Add a set of backup protection and measurement device on the medium voltage side to the main transformer with a medium voltage system, with the same model as KR-3430A.

Main functions

●Time limited overcurrent protection with three-stage composite voltage lockout (I and II segments can be directional)

●Matrix tripping method can be used to protect the export

●Start the main transformer air cooling; Overload lockout with on load voltage regulation

●Road remote signal input acquisition, remote signal displacement, accident remote signal

●4-channel pulse input

●Grounding zero sequence overcurrent protection (Section III)

●Non grounded zero sequence protection (zero sequence current blocking overvoltage, gap zero sequence)

●Flexible tuning; Overload signaling

●6 analog telemetry signals

●fault recording

KR-3410AWiring schematic diagram of high backup protection measurement and control device for three coil transformer

Note:

1. The high backup voltage is designed to be taken from the low voltage side PT, and if there are special needs, it should be gathered from the high voltage side PT