GE PQMII Instruction Manual page 145

CHAPTER 6: MONITORING
Note
PQMII POWER QUALITY METER – INSTRUCTION MANUAL
• Van, Vbn, Vcn: Displays phase voltages corresponding to the A, B, and C voltage
inputs. This voltage will be measured correctly only if the
, and
SECONDARY VOLTAGE WIRING
voltage does not match the actual voltage, check the setpoints and wiring. This
message appears only if the
• Iavg/Vavg: Displays the average of the three phase currents/voltages. This value is
not visible if the
VT WIRING
is set to "4 Wire Wye / 3 VTs", "4 Wire Wye Direct", "4 Wire Wye / 2 VTs", or "3
VT WIRING
Wire Direct" and L-L is displayed when
• Vab, Vbc, Vca: Displays line voltages corresponding to the A, B, and C voltage inputs.
The measured voltage is correct only if the
setpoints match the installed VTs. If the displayed voltage does not match the
WIRING
actual voltage, check the setpoints and wiring.
• AVERAGE LINE VOLTAGE: Displays the average of the three line voltages. This value is
not visible if the
VT WIRING
• VOLTAGE UNBALANCE: Displays the percentage voltage unbalance. Voltage
unbalance is calculated as shown below. If the
input, voltage unbalance is calculated using phase quantities. If the
configured as a delta input, voltage unbalance is calculated using line voltages.
Voltage Unbalance
where: = average phase voltage = (
V
avg
Wire Direct" connections;
= average line voltage = (
connection
= voltage in a phase (or line) with maximum deviation from
V
m
Even though it is possible to achieve unbalance greater than 100% with the above
formula, the PQMII will limit unbalance readings to 100%.
If the average voltage is below 10% of
Wire Delta / 2 VTs", "4 Wire Wye / 3 VTs", and "4 Wire Wye / 2 VTs" connections, or
below 10% of
VT RATIO
Wire Direct" connections, the unbalance reading is forced to 0%. This is implemented
to avoid nuisance alarms when the system is lightly loaded. If the simulation voltages
are being used, the unbalance is never forced to 0%.
• Van, Vbn, Vcn MIN/MAX: Displays the minimum/maximum phase voltage magnitudes
and the time and date of their occurrence. This information is stored in non-volatile
memory and is retained during loss of control power. The
CLEAR MIN/MAX VOLTAGE VALUES
• Vab, Vbc, Vca MIN/MAX: Displays the minimum/maximum line voltage magnitudes
and the time and date of their occurrence. This information is stored in non-volatile
memory and is retained during loss of control power. The
CLEAR MIN/MAX VOLTAGE VALUES
• V U/B MIN/MAX: Displays minimum/maximum voltage unbalance and the time and
date of its measurement. This information is stored in non-volatile memory and is
retained during loss of control power. This value is cleared with the
CLEAR DATA CLEAR MIN/MAX VOLTAGE VALUES
setpoints match the installed VTs. If the displayed
is configured for a wye input.
VT WIRING
setpoint is set to "Single Phase Direct". L-N is displayed when
VT WIRING
VT RATIO
setpoint is set to "Single Phase Direct".
VOLTAGE WIRING
V – V
m avg
-------------------------- - ×
=
V
avg
V
V + V
ab bc
×
VT RATIO
×
NOMINAL DIRECT INPUT VOLTAGE
setpoint clears these values.
setpoint clears these values.
setpoint.
,
VT RATIO VT NOMINAL
is set to "3 Wire Delta / 2 VTs".
, , and
VT NOMINAL SECONDARY
is configured for a wye
VT WIRING
100%
+ + ) / 3 for "Wye" and "3
V V
an bn cn
+ V ) / 3 for "3 Wire Delta / 2 VTs"
ca
VT NOMINAL SECONDARY VOLTAGE
for "4 Wire Wye/Direct" and "3
S1 PQMII SETUP
S1 PQMII SETUP
S1 PQMII SETUP
VOLTAGE
is
(EQ 0.2)
.
V
avg
for "3
CLEAR DATA
CLEAR DATA
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