Electro Industries/GaugeTech
Doc # E107706 V1.257-1
Chapter 7Transformer Loss Compensation
7.1:
Introduction
QThe Edison Electric Institute’s Handbook for Electricity Metering, Ninth Edition defines Loss
Compensation as:
A means for correcting the reading of a meter when the metering point and point of service are
physically separated, resulting in measurable losses including I2R losses in conductors and
transformers and iron-core losses. These losses may be added to or subtracted from the meter
registration.
QLoss compensation may be used in any instance where the physical location of the meter does not
match the electrical location where change of ownership occurs. Most often this appears when
meters are connected on the low voltage side of power transformers when the actual ownership
change occurs on the high side of the transformer. This condition is shown pictorially in Figure 7.1.
QIt is generally less expensive to install metering equipment on the low voltage side of a transformer
and in some conditions other limitations may also impose the requirement of low-side metering even
though the actual ownership change occurs on the high-voltage side.
QThe need for loss compensated metering may also exist when the ownership changes several miles
along a transmission line where it is simply impractical to install metering equipment. Ownership
may change at the midway point of a transmission line where there are no substation facilities. In
this case, power metering must again be compensated. This condition is shown in Figure 7.2.
M
Figure 7.1: Low Voltage Metering Installation Requiring Loss Compensation
Ownership Change
Figure 7.2: Joint Ownership Line Metering Requiring Loss Compensation
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Point of Ownership
Change