Technical information

5 – PARAMETER DESCRIPTIONS
62
P29 Ground Fault Level PFN 06
LCD Display
PFN:Gnd Flt Lvl
06 Off
Range OFF, 5 – 100 % FLA (Default OFF)
Description The Ground Fault Level parameter sets a ground fault current trip or indicate level that can be used to
protect the system from a ground fault condition. The starter monitors the instantaneous sum of the
three line currents to detect the ground fault current.
The ground fault current has to remain above the ground fault level for 3 seconds before the starter
recognizes a ground fault condition. Once the starter recognizes a ground fault condition, it shuts
down the motor and declares a Fault 38 (Ground Fault).
If a programmable relay is set to ground fault (GND), the starter energizes the relay when the
condition exists.
A typical value for the ground fault current setting is 10% to 20% of the full load amps of the motor.
Alarm
Condition
Fault
Trip
% Current
Delay
(Fixed 3 seconds)
Gnd Flt Lvl
PFN 06/P29
Time
NOTE: This is often referred to as residual ground fault protection. This type of protection is meant
to provide machine ground fault protection only. It is not meant to provide human ground fault
protection.
NOTE: The MX residual ground fault protection function is meant to detect ground faults on solidly
grounded systems. Use on a high impedance or floating ground power system may impair the
usefulness of the MX residual ground fault detection feature.
NOTE: Due to uneven CT saturation effects and motor and power system variations, there may be
small values of residual ground fault currents measured by the MX during normal operation.
See Also Relay Output Configuration parameters on page 70
Auto Reset parameter on page 64
Controlled Fault Stop Enable parameter on page 64