Phase to Phase votages in Metering
Phase to Phase votages in Metering
(OP)
Do customers generally what to see phase- phase voltages (VAB,VBC,VCA) or Phase -Neutral voltages (VAN,VBN,VCN) in the Feeder Protection Relay Metering despite of delta or wye connected PT inputs ?






RE: Phase to Phase votages in Metering
RE: Phase to Phase votages in Metering
Rafiq Bulsara
http://www.srengineersct.com
RE: Phase to Phase votages in Metering
Sorry about wrongly wording the previous post.
We do over/under protection on both PP, PN like 27P,59P, 27PP, 59PP . I would like to know what is the significance of 27P, 59P or metering P-N voltages?
RE: Phase to Phase votages in Metering
RE: Phase to Phase votages in Metering
RE: Phase to Phase votages in Metering
The ability to observe this P-N voltage unbalance may provide the customer a way to spot an impending problem before it reaches the over/under voltage protection trip points.
RE: Phase to Phase votages in Metering
RE: Phase to Phase votages in Metering
For protection and problem analysis phase to neutral voltages are often helpful.
In the old, old, ungrounded delta systems, voltmeters were sometimes used instead of lamps, or along with lamps for ground detection.
Bottom line, if the customer wants to check the incoming voltage, display phase to phase.
For protection and metering wye connected PTs and line to neutral voltages are often used.
Many display devices are capable of displaying more than one parameter. If you are using such a device, consider wye connected PTs and displaying line to neutral as well as line to line voltages.
Bill
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