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Chapter 2 Operating the EM720
Power Transformer/Line Loss Compensation
22
EM720 Power Quality and Revenue Meter
NOTES
1. When transformer correction is enabled, it is applied to all
instrumentation, billing and power quality calculations
and waveforms.
2. Transformer correction does not affect test LED pulse
outputs.
3. Transformer correction is not operational in test mode
regardless of the option’s status.
Power Transformer/Line Loss Compensation
Loss compensation allows accounting for losses in power
transformers and/or power line in the event the billing and
metering points are located at different sides of the power
transformer or at different sides of the power line.
The calculated compensation values for kW and kvar losses
are added to the measured power quantities and energies.
The compensation values will be either positive, or negative
depending on whether losses are calculated at the supply side
or at the load side of the power transformer. They will be
positive if the meter is located at the load side while the
billing point is on the supply side, and negative in the
opposite direction.
The instantaneous kW and kvar losses for iron and copper
can be read and inspected via communications.
See
Transformer/Line Loss Compensation Setup
on how to program the loss constants and enable
compensation in your meter. See
on how to enable and disable compensation in the
meter via the front display.
NOTES
1. When loss compensation is enabled, it is applied to all
billing data - one-second power values, power demands
and energy quantities. Loss compensation does not affect
instrumentation data – real-time power and fundamental
power values.
2. Loss compensation does not affect test LED pulse
outputs.
3. Loss compensation is not operational in meter test mode
regardless of the option’s status.
Operating Digital Inputs
The EM720 can monitor a total of 8 digital inputs including
four fast internal digital inputs and up to 2 replaceable two-
channel 2DI/2DO modules. See the EM720 Installation
Manual for digital input ratings and connection diagrams.
The 2DI/2DO module is provided with four indication LEDs
that show the status of the digital inputs and relay outputs: