P
AGE
6
OF
26
DGF100
reference
manual, rev 1, Feb 22, 2022
Ground
Fault
Systems
B.V.
device. The DGF100 resets automatically 3 seconds after the ground fault current is interrupted by
the tripping action of the circuit breaker. The output contact to the shunt trip coil opens. This
prevents damage to the internal mechanism of the circuit breaker in the event that the operator tries
to reset the circuit breaker. When the Control Voltage to the DGF100 is interrupted by action of the
shunt trip, the DGF100 resets with a short delay.
4.
Pulsed Non-failsafe Operation
The output relay does not change state when Control Voltage is applied or removed.
With Control Voltage on (green RUN LED alternating flashing one second on and off), when the
measured value reaches or exceeds the settings for current and time, the relay goes to the tripped
state for 0.5 seconds, then resets. The red TRIP LED will light.
Should the measured current remain or go above the set G/F trip level, this 0,5 second pulse is
repeated every 3 seconds. The red TRIP LED remains on until a RESET is activated. This allows the
user to verify which DGF100 tripped its associated breaker. If a RESET is not activated the red TRIP
LED remains on showing the cause of trip. However, the functionality of the trip circuit is not
compromised. That is, in case of a trip condition the relay will correctly issue a pulse, even if the red
TRIP LED is on.
If the Control Voltage is removed by the trip action of the output relay (i.e. it operates the shunt trip
of the breaker that is providing the Control Voltage) the red TRIP LED is turned off.
If the ground fault has not been cleared when Control Voltage is restored, regardless of the Trip
Delay time, after 500 milliseconds the relay goes to the tripped state for 0,5 seconds, then resets.
The red TRIP LED will turn on.
If the ground fault has been cleared when Control Voltage is restored, the unit will remain in reset
state and the green LED will flash.
If the DGF100 is to be used for alarm only purposes (rather than to interrupt ongoing processes), and the
alarm has to have an auto-resetting nature, then one has to use one of the Pulsed modes. The pulses will
be repeated as long as current is above the set G/F level.
2.2
LED Indicators
There are two LEDs on the front of the DGF100:
A green LED showing sufficient Control Voltage by slowly flashing (1 s on / 1 s off).
A red LED, if steady on, indicating a trip.
2.3
Reset/Test pushbutton
Either the built-in or an external, normally open, momentary pushbutton, connected to terminals R1 and
T2/R2, is used to reset the internal relay and/or the red LED (depending on the Operating Mode, see
). The external reset button must be a momentary normally open voltage-free contact; no
external power supply is required. See
A reset will only be granted if the cause of the trip is cleared. Otherwise the relay will remain activated
without glitches.
Double-clicking the built-in or external reset button invokes a test which switches an AC test-voltage onto
the built-in processor’s CS input. The voltage is scaled to simulate a residual current of 1,5 - 3 times the
G/F trip level. The unit will trip on G/F after the set delay (plus 0,4 s). The red LED turns on solidly. The
button needs to be pressed again to reset the device.
It is
NOT
necessary to press the RESET button after the ground fault has been cleared when the DGF100
is set in the Pulsed Auto Reset mode. In this mode the relay will reset in 3 seconds.
