SERVICE MANUAL R5888C
QUADRAMHO Chapter 5
Page 15 of 24
will operate. Any combination of SW1–5 can be selected to give the trip contacts
required for single or three phase tripping as required later.
Check that removing the link on the 1Z 10 test block terminals stops any contact
operation and the relay available LED ceases to be illuminated.
Note: All output tests are shown on Figure 7
Section 5. SCHEME TESTS
The appropriate tests should be made for the selected scheme option.
5.1 Zone 1 extension scheme (08 or 09)
In test 4.5 the non extended reaches were checked. Check that the opto isolator
input for reset Zone 1 extension (terminals A1–2) is not now energised. All the
Zone 1 ground and phase fault reaches will be increased by the setting on K15.
The nominal loop impedances required to check the reaches will be those given in
4.5.2 and 4.5.3, multiplied by K15. (Typically 20% of the second line section
would be covered by the extended reach).
The new reaches are found as in Section 4.5 for each fault condition.
When this scheme is being used with a relay specified for use with miniature
circuit breakers (MCB) instead of VT fuses, the reset Zone 1 extension opto is
shared with the carrier receive opto (according to the thumbwheel selection
number chosen) so instead of relay case terminals A1/A2, use A9/A10.
5.2 Permissive underreach scheme (02 or 03)
Note: that if the channel in service opto isolator is not energised 3 phase trips
will be given in scheme 02. Connect a double pole switch so that one
pole of it can be used to energise the signal receive opto isolator input
(Terminals A9–10) and the other pole to start a timer.
5.2.1 Aided trip check
Energise the opto isolator input and check that application of a Zone 2 fault gives
an instantaneous aided trip. Make sure a Zone 2 time delayed trip is obtained
when the signal receive is removed.
5.2.2 Signal receive delay on drop-off
This delay is fixed at 100ms and a signal is available from the monitor point box
(Terminals 2–9) for checking it. The signal is active low falling from 24 volts, timers
will treat it as a contact provided terminal 2 is connected to the common terminal
of the timer.
Start the timer when de-energising the opto isolator input and stop it from the
monitor point box signal when it changes to 24V. (The timer should be set to
normally closed for start and stop). The measured time should be 90–110ms.
5.2.3 Signal send checks
Check that applying a Zone 1 fault causes the signal send contacts (B1–B2 and
B3–B4) to close.
There is also a test option which can be used to give signal send which is useful for
checking the signalling channel on the system. Select test option 62 and if SW8 is
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