Page 451 - IRSEM_Main Book

(i) Detailed specifications & instructions for inspection and testing of different
types of equipment as applicable to them should be available.

(j) All other equipment such as lever frames, LC gates, cable sheaths, signal
screens, location huts, etc. in AC. electrified areas shall also be properly
earthed as stipulated in Chapter 22 of SEM.

(k) No equipment is due for overhauling.

19.8.5 Checking of the Wiring:

(a) Point to point testing: Wiring shall be checked to ensure that it has been
carried out as per approved wiring diagram. Point to point testing shall be
carried out before plugging in the relays. Wires shall be tested one by one
for continuity and insulation. While doing continuity testing, wire count test
shall also be done to verify the number of wires present on each contact.

(b) Wire Count Test: Prior to conducting continuity and insulation test, contact
occupancy test must be carried out for each relay as per the contact
analysis made. The number of contacts allotted and wires at each contact
must tally.

Recommended practice: while dealing with wiring alterations, it is recommended to

adopt a clear system for deletions, additions such as colour code. For example, Green
colour for deletions and red colour for additions. Similarly a system of checking of
such deletions/additions by a tick and second level checking by cross tick on drawing
sheets/separate wiring sheets or any other suitable protocol may be adopted duly
explaining to staff concerned, to give clarity and avoid rework.

19.8.6 Test of Individual Circuits

(a) It shall be checked that each individual circuit is actually controlled by the
proper contacts of the relays and other devices as per wiring diagram.

(b) Where feed to a particular device is controlled through two or more paths
in parallel, the check of each path must be carried out separately.

(c) Cases of intermittent or continuous extraneous feed of even small
magnitude or wrong operation of any relay observed shall be investigated
thoroughly and remedial action taken to rectify the fault.

(d) Once the indoor wiring works are completed before conducting the system
Integrity testing, simulation test must be conducted by simulating field gears
such as Track circuits, Signals & Points on a simulation panel. This will
ensure the correctness of indoor wiring before connecting to outdoor gears.

Chapter 19: Installation, Testing & Maintenance of Signalling Equipment Page 399 of 535