48049-137-05EN

Appendix D—Trip Unit Voltage Supply Architecture

The trip unit has an integral internal three-phase voltage power supply which appears as a three-phase delta configured load to the system (Integral Internal Three-phase Power Supply). This power supply is a three-phase load by itself and will inject voltage on an open phase (Open Phase on Three-phase Power Supply). The impact of a three-phase delta configured load on the voltage-based protection functions is as follows:

NOTICE
Hazard of equipment damage
Setting undervoltage protection (Vmin) below 80% or voltage unbalance (Vunbal) above 20% can cause the trip unit to not perform as expected.
Failure to follow these instructions can result in equipment damage.
QR Code is a registered trademark of DENSO WAVE INCORPORATED in Japan and other countries.

Was this helpful?