1011-530
48
Calculated Alarm
Level
Verify the Calculated Alarm Level (capacitor banks only – optional)
1. Check that no capacitor units have been isolated from the bank.
2. De-energize the capacitor bank.
Open the capacitor bank switching device. Then ground the bank, observing estab-
lished operating procedures and safety precautions.
3. Isolate the number of capacitor units calculated to set the alarm.
To isolate the number of capacitor units (all in the same series group) previously calcu-
lated to set the alarm, remove their respective fuses.
For grounded wye-connected banks where the number of series groups per phase is
odd,
you will not have to isolate as many capacitor units in a series group located
between the tap point and ground as in a series group located between the tap point
and the line.
4. Remove the temporary grounds, re-energize the bank, and record the
voltage.
If the voltage is greater than the alarm level, the control device will generate an alarm
once the “Alarm Time Delay” ends. The
ALARM INDICATOR
LED will also turn ON.
As soon as you read the voltage, open the capacitor bank switching device to avoid
shortening the life of the capacitor units. Verify that no other capacitor units have been
isolated.
NOTE: You must press the
ALARM INDICATOR
button to clear the alarm.
5. De-energize and ground the capacitor bank, then reconnect the fuses.
Observe established operating procedures and safety precautions to de-energize and
ground the capacitor bank. Reconnect the fuses you previously removed to isolate the
capacitor units.
6. Repeat Step 1 through Step 5 for each remaining phase leg of the
capacitor bank.
7. For ungrounded wye capacitor banks, compare the calculated alarm
level and the measured voltages.
Check that the calculated alarm level is lower than the lowest voltage just measured. If
the calculated level is higher than one or two of the voltage readings, then the system
voltage imbalance and/or inherent capacitor bank imbalance is creating an error volt-
age between the bank neutral and ground. This error is large enough to obscure the
neutral-to-ground voltage resulting from the isolation of successive capacitor units.
Summary of Contents for BankGuard PLUS
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