4 verifying current and energy, Erifying, Urrent – GE Industrial Solutions EPM1500 Single Point Submetering System User Manual

Page 30: Nergy

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3–6

EPM 1500 SUB-METER – INSTRUCTION MANUAL

CHAPTER 3: USING THE METER

3.3.4

Verifying Current and Energy

Z

Press and hold the Display Scroll button until the following menu
heading is displayed:

Z

Release the Display Scroll button. Scroll down by pressing and
releasing the Display Scroll button until the following submenu is
displayed:

The A(mperage) reading in the display above will always be a positive number, even if the
CT was incorrectly installed. Check the reading to see if it indicates the approximate
current you expected. Remember that this applies to Phase 1 only. If all the numbers on the
multiplier screen were 1.00 and the current transformers are 100:0.1, your multiplier is 1
and the readings are the actual values. If the CTs are 200:0.1, multiply the current reading
by 2.

The W(att) reading will also count forward as your view the LCD. A negative power reading
is indicative of an incorrectly installed CT, or one that is cross-phased with the wrong
voltage (phase) leg. The R(eactive) reading can be negative, depending on the nature of the
load. Negative values indicate a capacitive load while positive values indicate an inductive
load.

Z

Scroll down by pressing and releasing the Display Scroll Button
until the following submenu is displayed:

Under normal conditions the phase angle (x.x°) should be close to 0° and the power factor
should be a number close to 1 (one). Resistive loads will have a power factor close to 1,
while inductive loads will typically reflect a power factor between 0.80 to 0.95, or even
lower.

If the phase angle on the lower left is a number close to 180°, it indicates the CT was
installed backwards, or 180° out-of-phase. If the number is close to 120°, at least two CTs
have been cross-phased, and a similar number will appear in the phase angle data in
Phase 2.

Z

To view screens for Phases 2 and 3, repeat the same steps as
above.

Phase Diagnostic

Registers

Phase 1

7.468 A

818.7 W

100.5 R

Ph 1

935.4 VA

6.8°

.875 PF

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