PUB 51079
D64RP14 SERIES A2 DIGITAL GROUND FAULT RELAY
Revision 1
May, 2005
Page 7
As indicated in the General Description, it is recommended that the ground fault TRIP LEVEL setting
be kept as close to the charging current as possible. This will provide maximum safety for operating
personnel and equipment protection. On resistance grounded systems, the TRIP LEVEL setting
should be set lower than 20% of the Neutral Grounding Resistor let-through current.
If the measured ground fault current exceeds the TRIP LEVEL setting, the output relay changes state
after the pre-selected TRIP DELAY time.
2.2.2
GROUND FAULT TRIP DELAY TIME – DIPSWITCHES 4, 5, & 6
The ground fault TRIP DELAY time range is 0.5 - 10.0 seconds. Table 1 provides a listing of the eight
TRIP DELAY settings, which can be made with DIPswitches 4, 5, & 6.
The TRIP DELAY time begins when the ground fault trip level setting is reached or is exceeded.
Set the ground fault TRIP DELAY time to provide the desired delay before the output relay changes
state when the ground fault TRIP LEVEL setting is reached or exceeded.
The setting should be selected to co-ordinate with other ground-fault devices connected on the same
transformer secondary: set shorter than upstream devices; set longer than downstream devices. If no
other ground-fault devices are connected, set for the shortest time.
2.2.3
OUTPUT RELAY OPERATING MODE - DIPSWITCHES 7 & 8
Referring to the Glossary of Terms, determine if FAILSAFE, NON-FAILSAFE, or PULSED AUTO
RESET operation of the output relay is required. The factory setting is NON-FAILSAFE with
DIPswitches 7 & 8 in the
D
own position.
Refer to Table 1 for DIPswitch settings for FAILSAFE and PULSED AUTO RESET operation.
2.3
OUTPUT RELAY CONTACT STATE
The output relay contact state is determined by the operating mode selected and the sensing condition
of the D64RP14 relay. This is shown in Table 2. Use this table when deciding on field connections.
Refer to the CONNECTIONS section.
2.4
INDICATION
There is one green LED on the front of the D64RP14:
Off:
No control voltage or D64RP14 defective
Slow Flashing: Okay, control voltage on
Fast Blinking:
Ground Fault Trip
Steady On:
Control voltage too low or D64RP14 defective
2.5
RESET
The D64RP14 has two terminals R1 and R2 for a remote N.O. Test/Reset button. After a trip, the
electronics remain in the tripped state until the ground fault has been cleared and the Reset button has
been pressed, or the control voltage is removed from terminals L- & N+.
It is
NOT
necessary to press the remote Test/Reset button after the ground fault has been cleared
when the D64RP14 is set in the Pulsed Trip Auto Reset mode. In this mode the relay will reset
automatically in 3 seconds.
2.6
GROUND FAULT TEST
Double clicking the external button connected to terminals R1 and R2 invokes a relay test. A simulated
current equal to 1.2 times the trip current set on the Trip Level DIPswitches replaces the measured
current. After the trip delay time set on the Trip Delay DIPswitch has elapsed, the unit should trip and
the green LED will fast blink. This procedure tests the functionality of the unit.
