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Section 1.

INSTALLATION

1.1

General

Protective relays, although generally of robust construction, require careful
treatment prior to installation.  By observing a few simple rules the possibility of
premature failure is eliminated and a high degree of performance can be expected.

The relays are either despatched individually or as part of a panel/rack mounted
assembly in cartons specifically designed to protect them from damage.

Relays should be examined immediately the are received to ensure that no
damage has been sustained in transit.  If damage due to rough handling is evident,
a claim should be made to the transport company concerned immediately, and
GEC ALSTHOM T&D Protection & Control promptly notified.  Relays which are
supplied unmounted and not intended for immediate installation should be returned
to their protective polythene bags.

1.2

Unpacking

Care must be taken when unpacking and installing the relays so that none of the
parts are damaged or their setting altered, and must be handled by skilled persons at
all times.

Relays should be examined for any wedges, clamps, or rubber bands necessary to
secure moving parts to prevent damage during transit and these should be removed
after installation and before commissioning.

Relays which have been removed form their cases should not be left in situations
where they are exposed to dust or damp.  This is particularly applies to installations
which are being carried out at the same time as construction work.

1.3

Storage

If relays are not installed immediately upon receipt they should be stored in a place
free from dust and moisture in their original cartons and where de-humidifier bags
have been included in the packing they should be retained.  The action of the de-
humidifier crystals will be impaired if the bag has been exposed to ambient
conditions and may be restored by gently heating the bag for about an hour, prior to
placing it in the carton.

Dust which collects on a carton may, on subsequent unpacking, find its way in to the
relay; in damp conditions the carton and packing may become impregnated with
moisture and the de-humidifying agent will lose its efficiency.

The storage temperature range is –25

°

C to +70

°

C

1.4

Site

The installation should be clean, dry and reasonably free from dust and excessive
vibration.  The site should preferably be well illuminated to facilitate inspection.

An outline diagram is normally supplied showing panel cut-outs and hole centres.
For individually mounted relays these dimensions will also be found in Publication
R6035.

Publication R7012 is a parts catalogue and assembly instructions.  This document
will be useful when individual relays are to be assembled as a composite rack or
panel mounted assembly.

Summary of Contents for MCAG 19

Page 1: ...Types MCAG 19 39 Protective Relays Service Manual R8035F ...

Page 2: ......

Page 3: ...g 5 2 7 Main current transformers 5 2 8 Equipment required 5 2 9 Electrical tests 5 2 10 Output Contacts 6 3 MAINTENANCE 6 4 MECHANICAL SETTINGS 6 4 1 General 6 4 2 Contact setting 7 4 3 Mechanical flag setting 7 5 PROBLEM ANALYSIS 7 5 1 Failure to operate 7 5 2 Operating at the incorrect values 8 5 3 Output contacts 8 5 3 1 Output contacts not operating mechanically 8 6 SPARES 8 7 COMMISSIONING T...

Page 4: ...ave been removed form their cases should not be left in situations where they are exposed to dust or damp This is particularly applies to installations which are being carried out at the same time as construction work 1 3 Storage If relays are not installed immediately upon receipt they should be stored in a place free from dust and moisture in their original cartons and where de humidifier bags h...

Page 5: ...diagram number appears inside the case 2 4 Commissioning preliminaries To gain access to the relay first loosen the captive cover screw and carefully remove the cover from the case The module can then be removed from the case by grasping the handles at the top and bottom of the front plate and pulling forwards Care must be taken to ensure that mechanical settings of the element are not disturbed C...

Page 6: ...y circuit of a live ct since the high voltage produced may be lethal to personnel and could damage insulation 2 8 Equipment required A current source capable of supplying sinusoidal current at the appropriate test current levels An ammeter with the appropriate current range 2 9 Electrical tests Set the plug bridge to its lowest value Set xIs potentiometer to 1 Slowly raise the current until the re...

Page 7: ... be checked as per Section 4 and if any adjustment is made then Section 2 should be repeated Section 4 MECHANICAL SETTINGS 4 1 General Armature gap measurements should be made with the top of the feeler gauge level with the centre line of the core Contact pressures are measured with gramme gauge at the contact tips In general contact gaps and follow through are defined by quoting an armature gap a...

Page 8: ...ch is located between the contact blades near to the contact blocks Contact settings for Normal duty make and break short hand reset contacts 4 3 Mechanical flag setting With the armature closed onto a 0 015 feeler gauge the flag should be free to fall but should not fall using a 0 020 feeler gauge Adjustment is made to the catch spring on the flag Section 5 PROBLEM ANALYSIS 5 1 Failure to operate...

Page 9: ...lock and relay contacts Contacts contaminated these should be cleaned with a burnishing tool supplied in relay tool kits On on account should knifes files or abrasive materials be used Check mechanical settings as per Section 4 5 3 1 Output contacts not operating mechanically Push rods not correctly located Check electrical connections Flag spring may be distorted holding the armature open Section...

Page 10: ...________________ Diagram __________________________ Setting ____________________________ 1 Pick up check Phase Setting Operate current A B C Delete if not applicable 1 1 Check reset drop off is 80 of Is __________ 2 Check flag indicator __________ 3 Check contact operation __________ 4 Remarks ___________________________________ ____________________________________ Commissioning Engineer Customer ...

Page 11: ...Page 10 ...

Page 12: ... Battery Power supply AC current _____________ Main CT Test set Frequency _____________ 2 Which type of test was being used ________________________________________ 3 Were all the external components fitted where required Yes No Delete as appropriate 4 List the relay settings being used ______________________________________________________________________ _________________________________________...

Page 13: ...________________________________ ______________________________________________________________________ 9 Was there any visual damage ______________________________________________________________________ ______________________________________________________________________ ______________________________________________________________________ 10 Any other remarks which may be useful ____________...

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Page 16: ...AREVA T D s Automation Information Systems Business www areva td com T D Worldwide Contact Centre online 24 hours a day 44 0 1785 25 00 70 http www areva td com contactcentre Publication R8035F ...

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