High Speed Busbar Transfer (HBT) like ATS

HBT

1. Highspeed Busbar Transfer (HBT) Main Feeder/Source Standby feeder/source Load BUS CB 1 CB 2 V Feeder Source I Feeder Source I Standby Feeder Recommended Transfer BUS

2. Blocking signal 86 Trip Signal Signal main & standby feeder 51/51N Signal main & standby feeder CB Undefined Position Block from Device Other Feeder Not Healthy Bus /other feeder Voltage <0.7Un 87 bus active Manual Blocking signal Trigger Signal Ready Signal from HBT Delta Freq < 1Hz Delta Degree <20deg CB Position Close / OPEN Condition 27 signal confirm by VT CB OPEN Manual Transfer Signal Permissive Signal

3. Requirement for this HBT System CB must have highspeed closing time VT sensing on BUS VT Sensing on Main & standby feeder CT sensing on Feeder