GE AKR-30 Series Maintenance Manual page 161

SECTIO N 1 4-MicroVersaTrip® Plus and M icroVersaTrip® PM Trip Units
1 4.9 TROUBLE-SHOOTI NG G U I D E
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The following g u i d e is provided for trouble-shooting and
isolating common problems.
possi ble condition . Contact the Customer Sup port at
800-843-37 42 if the problem is not resolved by these
procedures.
Symptom
1 . The trip unit display
is blank.
2. The trip unit display
flashes.
3. The trip unit display
flashes ERR.
4. The trip indication
target will not clear.
5. Unit does not com­
municate with the
Monitor, POWER
LEADER Distribution
Software, or FPU.
6. Current readings are
incorrect.
7. Voltage readings are
incorrect.
8. kW legend is flashing.
9. Overload target is
flashing by itself.
It does not cover every
Possible Cause
Line current is below 20%
of S (MicroVersaTrip Plus).
External 24 Vdc is absent
(MicroVersTrip® PM).
Can occur on Plus style trip
units when load current
fluctuates near 20% of S.
The built-in self test has
detected an error.
Trip unit is not in status
mode.
Commnet wires are shorted
or improperly connected.
FPU version is lower than 2.0
Trip unit address incorrect.
Rating plug value was
defined incorrectly.
Potential transformer (PT)
primary voltage was defined
incorrectly.
PT connection was defined
incorrectly.
Total power metering.
Test Kit-initiated trip indication.
Corrective Action
At least 20% of the current sensor rating, S, must
be flowing through the breaker to activate the
display. If not, power the trip unit with the Test
Kit or external battery pack.
Check that the control power supply is present
and operational.
Power the trip unit with the Test Kit or external
battery pack.
Replace the trip unit.
Press FUNCTION until STATUS is displayed. Press
SELECT and VALUE together to clear the target.
Locate and repair the short or the incorrect con­
nection.
U pdate FPU to version 2.0 or higher.
Check that address assigned to trip unit agrees
with address at host.
Read the X value from the rating plug name
plate and enter this with the rating plug current
set point procedure . Do not enter the sensor
rating, S.
Read the PT ordinary rating from the PT name
plate and enter this value with the PT primary
voltage procedure .
With the PT connection procedure , enter VL-N for
a wye-connected PT primary or VL -L for a
delta-connected PT.
Indicates that the total power is metered in kVA.
Clear target as indicated above (Symptom 4).
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