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

●Four stage composite voltage blocking overcurrent protection (sections I, II, and III can have direction, section IV does not have direction)

●Matrix tripping method can be used to protect the export

●Start the main transformer air cooling; Overload lockout; on-load tap changing

●Flexible setting of overload signaling

●fault recording

●10 channels of remote signaling input acquisition, remote signaling displacement, and accident remote signaling

●6-channel analog telemetry; 4-channel pulse input

●Statistics of accident disconnection frequency and event SOE, etc

KR-3430AWiring schematic diagram of low backup protection measurement and control device for three coil transformer

Note:

1. The voltage is taken from the local voltage

2. This diagram is applicable to the backup protection of the low and medium voltage side of the three coil transformer