M Echan Ical I Nspection; E Lectr Ical Tests; Drawout Relays, Genera L - GE IAV51A Instructions Manual

Remove the relay from its case and check that there are no bro ken or cracked molded pa rts
o r other s i g n s o f p hysical d amage, and that a l l screws a re tight. Check that the s h o rti n g
bars a re i n t h e proper locatio n (s) a n d that they a re properly formed (see Fig u re 9 ) .

M ECHAN ICAL I NSPECTION

1 . On re lays that h ave time d i a ls, the d ials wi l l be set at zero (0) before the relay leaves
the facto ry. It is necessa ry to change this setting in order to open the relay contacts.
2. On a l l rel ays with locked time d i a ls, make sure the two ti me-d i a l lock i n g screws a re
tig ht. Th ese lock i n g screws are to prevent the d ia l from movi n g when the relay is
su bjected to h i g h o perati ng torq ue.
3 . The movi ng contact sh o u ld be faste ned secu rely i n its support and should engage the
stati o n a ry contact about in the midd le, o r at least 1 /1 6 i n ch i nside, the peri p h e ry of
the stationary contact.
4. The stop-arm leaf spri ng shou ld deflect about 1 /64 i n ch and the sto p a rm s h o u l d clear
the molded block by at least .020 i nch .
Any fore i g n material must be cleared out of a l l a i r g a ps. Cleara n ce between the d is k
5.
and e ither t h e d rag magnet or U-mag net shou l d b e a t l east 0 . 0 1 0 i n ch f o r a n y
position o f the d isk.
End play of the d isk should be from 0.005 i nch to 0.0 1 0 i n ch . End play sh o u l d not be
6.
so g reat as to a l l ow the d isk to stri ke the U-mag net or the d rag mag net. Check that
top and bottom pivot and bea ring screws a re tig ht.
7 . There should be no noticeable friction i n the rotati ng structu re.
Rotate the time d ia l to the zero position (0) . Check by mea n s of a neon lamp th at the
8.
contacts j ust close . There should be approximately 1 /32 i n ch wi pe on the stat i o n a ry
contact. If the contact does not cl ose, adj ust the d isk position by back i n g off the two
cl a m p i n g screws on the stop arm and rotati ng the stop arm rel ative to the cutout i n
the d isk. This provides a coa rse adj ustment. Retighten the cl a m p i n g screws.
For fi ne adj ustment of contact closing, run the stationary contact brush i n or out by
means of its adj usti n g screw; after th is adj ustment, check that the screw is h e ld firmly
in its s u p port.
9 . O n dou ble-th row rel ays, the su pport post o f t h e u p p e r spri n g s h o u ld c l e a r t h e
i ns u l ating pl ate b y a t least 1 /64 i nch .
E LE CTRICAL TESTS
A.

Drawout Relays, Genera l

S i n ce a l l d rawout relays i n service ope rate i n the i r cases, i t is recom mended that they
be tested i n the i r cases or a n eq u ivalent steel case . I n th is way any mag n etic effects of
the enclosu re w i l l be accu rately d u pl i cated d u ri n g testi n g . A relay may be tested
without remov i n g it from the panel by usi ng a 1 2XLA 1 3A test p l u g . T h i s p l u g m a kes
con n ections o n l y with the relay, and does not d istu rb a n y shorting bars i n the case . Of
cou rse, the 1 2XLA 1 2A test plug may a lso be used . Alth o u g h th is test p l u g a l lows
g reater testing flex i b i l ity, it also req u i res CT shorting j u m pers and the exe rcise of
g reater ca re, si nce con nections are made to both the rel ay a n d the exte r n a l ci rcu itry .
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