Mechan I Cal I Nspect I On; El Ectri Cal Tests - GE IAV51A Instructions Manual

CAUT I ON
EVERY C I RCU IT I N THE DRAWOUT CASE HAS AN AUX I L I ARY BRUSH .
C I RCU ITS ANU OTH ER C I RCUITS W I TH SHORT I NG BARS THAT THE AUX I L IARY BRUSH BE B ENT H I GH ENOUGH TO E NGAGE THE
CONNECT I NG PLUG OR TEST PLUG B EFORE TH E MAI N B RUSHES DO .
B E I NG OPENE D .
�!ECHAN I CAL INSPECT I ON
1 . On rel ays wh i ch have time d i a l s , the d i a l s wi l l be set a t zero before the rel ay l ea ves the fac tory .
I t i s necessary to change th i s setti ng i n order to open the rel ay contacts .
2 . On a l l rel ays wi th l ocked time di al s , make sure the two time-d i a l l ock i ng screws are ti gh t .
l ock i ng screws are to prevent the di a l from mov i ng when the rel ay i s s ubjected to h i gh operati ng torq u e .
The mov i ng contact shou l d be fas tened secure l y i n i ts support and shou l d engage th e s tationa ry contact
3 .
about i n the mi ddl e or at l ea s t 1 / 1 6 i nc h i ns i de th e peri phery of the s tati onary contact .
4 .
The s top arm l eaf s pri ng shoul d defl ect about l /64 i nch and the s top arm shou l d cl ear the mo l ded bl ock
by at l east . 02 0 i nc h .
5 . Any fore i g n materi al mus t b e cl eaned out o f s tator a i r gaps .
the drag mag�et or U-magne t shou l d be a t l east 0 . 0 1 0 i nch for any pos i ti on of the di sk .
6 . E nd pl ay of the di sk shou l d be from 0 . 00 5 i nch to 0 . 0 1 0 i nch .
al l ow the d i s k to s tri ke the U -magnet or the d rag magnet.
screws are t i g h t .
7 . There shoul d b e n o noti ceab l e fri cti on i n the ro tati ng s truc ture .
8 .
Rotate the time d i a l to the zero pos i ti o n .
There shou l d be approxima tel y 1 /3 2 i nch wi pe on the s ta ti onary contact .
c l os e , adj u s t the d i s k pos i ti o n by back i ng off the two cl amp i ng screws on the s top arm and rota ti ng
th e s top arm rel ati ve to the cu tout i n the di s k .
c l ampi ng screws .
For fi ne adjus tme n t of contact c l os i ng , run the s tati onary contact b rush i n or out by means of i ts
adj usti ng screw ; after th i s adj us tmen t , check that the screw i s he l d fi rml y i n i ts support .
9 . On doubl e- throw rel ays , the support pos t of the upper spri ng s h oul d cl ear the i ns u l ati ng pl ate by at
l east 1 /64 i nch .

EL ECTRI CAL TESTS

A. DRAWOUT RE LAYS GENERAL
S i nce al l drawout rel ays i n serv i ce operate i n the i r cases , i t i s recommended that they be tes ted i n
thei r cas es or a n equ i va l ent s teel . cas e .
accura te l y dupl i cated duri ng tes ti n g .
a 1 2 XLA1 3A tes t pl ug .
bars i n the cas e . O f course , the 1 2XLA1 2A te s t pl ug may al so b e us ed .
greater tes ti ng fl exi b i l i ty , i t al so requi res CT s horti ng j umpers a nd the exerc i se of g reater c a re s i nce
connec ti ons are made to both the �el ay and th e external c i rcui try .
B . POWER REQU I REMENTS GENERAL
Al l al terna ti ng-current operated devi ces are affec ted by frequency .
can be anal yzed as a fundamental frequency pl us harmoni cs of the fundamental frequency , i t fol l ows th at
al terna ti ng-c urrent devi ces ( re l ays ) wi l l be affec ted by the appl i e d waveform .
Therefore , i n order to properly tes t al terna ti ng-cu rrent rel ays i t i s essenti al to use a s i ne wave
of current and/or vol tage .
expres sed as a fi ni te number for any parti cul ar rel ay , h owever , any rel ay us i ng tuned c i rcu i ts , R-L or
RC networks , or satura ti ng el ec tromagnets ( s uch as time-overcurrent rel ays ) woul d be essenti a l l y affected
by non - s i nusoi dal wave forms .
S i mi l ar l y , rel ays requ i ri ng d-e control power shoul d be tested us i ng d - e power and not ful l wave
rec ti fi ed powe r . Unl ess the rec ti fi ed s upply i s we l l fi l tered , many rel ays wi l l not operate properl y due to
the d i ps i n the recti fied power .
rul e the d - e source shoul d not conta i n more th an 5 percent ri pp l e .
I n th i s way any magneti c effects o f the encl osure wi l l b e
A rel ay may be tes ted wi thout remo v i ng i t from the panel b y u s i ng
Th i s pl ug makes connecti ons onl y wi th the re l ay a nd �oes not di s turb any shorti ng
The puri ty of the s i ne wave ( i . e . i ts freedom from harmon i c s ) �annot be
Zener d i odes , for exampl e , . can turn off duri ng these d i ps .
G EH-1814
IT I S ESPECIALLY I MPORTANT ON CURRENT
TH I S W I L L PREVENT CT SECONDARY C I RCU ITS FROM
Cl earance between the d i s k and e i ther
End pl ay shou l d not be so g reat as to
Check that top and bottom p i vot and beari ng
Check by means o f a neon l amp th a t the contacts j u s t cl ose .
Th i s prov i des a coarse adjustmen t .
8
I f the contact does not
Reti g h ten the
Al though th i s tes t pl ug a l l ows
S i nce non-s i nusoi da l waveforms
As a genera l
These