TCI HG7 - Manual (Page 40)

P O W E R M O N I T O R P A C K A G E O N L Y
POWER MONITOR OPTION HG7 I, O, & M Manual 38
FAULT
Code
Troubleshooting Procedure
F31-F33 Filter Over-current Delayed Trip
The usual causes for a F31 displayed fault are:
Short-term operation above rated line current during acceleration of the load or other
normal utilization of the drive's short-term overload capacity.
Operation above rated line current due to abnormal drive overload condition.
Excessive harmonics present on the distribution system from other sources.
Partial loss of capacitance (thus causing the filter circuit tuning point to shift to or
above the designed frequency).
Line voltages greater than 125% of the nominal rating.
Interaction with power factor capacitors on the distribution system resulting in system
resonance conditions; however, not to the level that would cause a fast trip as
indicated by the display of F2x fault.
If the problem is caused by short-term (<60 seconds) operation above rated line current
due to normal utilization of the drive's short-term overload capacity, increasing the time to
fault setup parameter (1A) may alleviate the problem.
If F31-F33 faults occur repeatedly in the apparent absence of any of the above problems,
verify the actual filter current with a current probe suited for true RMS measurements in a
harmonic rich circuit. Note: It may be necessary to inhibit the board from de-energizing
the HG7 by operating in the calibrate mode. However, be aware that if excessive currents
are indeed present, the technician must be able to rapidly remove power from the filter to
minimize damaging components or operating the filter fuses.
If the actual measured currents are within the acceptable levels for the rating of the filter,
but there are short periods (<60 seconds) that exceed the trip threshold, increasing the
time to fault setup parameter (1A) may alleviate the problem.
The factory default setting for the Filter Over-current Delayed Trip (parameter 6A) is 160%
of the filter’s nominal fundamental current rating as determined by the filter’s kVar,
frequency, and voltage ratings (parameters 3A, 4a & 8A). It may be acceptable to
increase the slow trip parameter setup 6A. However, it is recommended that you consult
the technical support department at the factory if this becomes necessary.
Troubleshooting Units Equipped with Pilot Lights
Units rated 20 kVar and less, or over 120 kVar, have Blown Fuse and Filter Enabled pilot lights to
indicate their operating status and are not equipped with the HG2 Protection Monitor as standard.
Troubleshooting information for units equipped with the HG2 Protection Monitor is provided in the
previous section under the heading Troubleshooting Units Equipped with the HG2 Protection Monitor.
Filter Enabled Pilot Light
The Filter Enabled pilot light indicates that the Filter Enable input is closed.
Blown Fuse Indicating Pilot Lights
If a Blown Fuse Indicating pilot light is illuminated, the corresponding fuse, Fu1(a), Fu2(a), or Fu3(a)
has blown. These fuses protect the three-phase HG7 filter power circuitry. Check for damaged
components or wiring in the filter power circuit. Check for discolored or burned components and
deformed or leaking capacitors. Damaged components can be caused by overheating. Check to see that
the ambient temperature is not excessive and make sure that the unit is receiving an adequate flow of
cooling air. Check the fan if the unit has one.