System - GE 845 Instruction Manual

CHAPTER 4: SETPOINTS

System

845 TRANSFORMER PROTECTION SYSTEM – INSTRUCTION MANUAL
To measure and function properly, the following information must be entered on the
845 relay:
• Current Sensing: information related to phase and ground CT primary ratings
• Voltage Sensing: information related to Phase and Aux. VT connections, secondary
voltage, and VT ratios
• Power Sensing: information related to voltage and current banks polarity residing on
the same card
• Power System: information related to system frequency, tracking frequency, phase
rotationTransformer: information related to transformer losses, temperature rise over
ambient, winding resistance, type of transformer, capacity, winding voltage, phase
shifting, grounding, etc.
• Breakers: information related to detecting the status of breakers by assigning contact
inputs
• FlexCurves: information related to inverse time curves with user-programmable points
SYSTEM
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