SERVICE MANUAL R5888C
QUADRAMHO Chapter 6
Page 4 of 12
4.4 Trip test function check
During this test the trip contacts will close so care is needed if the contacts are
connected to a system.
Select option 88 and using the information in Figure 3 select the appropriate
switch to the right and check the trip contacts close when the reset pushbutton is
pressed. Return SW1-5 to the left.
After this test, the contacts can be prevented from closing by removing the link
across 1Z-10. This will extinguish the relay available LED.
4.5 On angle reach checks
4.5.1 Zone 1 reach tests
i) The relay should now be connected to equipment able to supply three phase to
neutral volts and current in the correct phase relationship for a particular type of
fault on the selected relay characteristic angle. The facility for altering the loop
impedance (phase and ground fault compensation or phase and phase)
presented to the relay is essential. This may be a continuous adjustment or steps
of around 1% in the voltage or current.
The voltage supply to any test set working off 3 phase supplies should be
checked for correct phase rotation.
The test blocks should be connected as shown in Figure 4. Select option 00.
ii) Ground faults
Commence with connections for an A-G fault. To establish confidence in
operation a close-up fault with adequate source impedance to limit the current
should be applied. The LED marked A should light followed by Z2 and Z3 if the
fault is left on.
The current should then be reversed to check that operation does not occur,
except for Z3 if set with some reverse reach.
The appropriate loop impedance should now be presented to the relay.
K14 (K1 + K2 + K4 + K5 + K6) (K11 + K12 + K13)
ohms
I
n
or the nearest available above.
Make small step adjustments to the impedance, only presenting it for less than
Zone 2 time to the relay and determine the highest impedance which gives
instantaneous illumination of the A LED (if a low Zone 2 time is set it may help
to increase it temporarily).
The measured impedance should be within 10% of the calculated value
assuming the angle of the impedance presented is within 5° of Ø
Ph
and Ø
N
on
module 7 of the relay. (This applies for all later impedance checks).
Repeat the tests for B–G and C–G including the directional checks.
Note: The indications are automatically reset when a new trip output is
obtained, but it may be easier to understand what happens by using
the manual reset on module 4.
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