Contact Cleaning; Se Rvici Ng An D Adj U Stm E Nts; Tar G Et A N D Seal-In U N It; Vo Lta G E Seiti N G - GE IAV51A Instructions Manual

CONTACT CLEAN I N G
F o r clea n i n g fine silver contacts, a flexi ble b u rn ish i n g tool sh o u l d b e used . Th is consists o f a
flexi b l e str i p of meta l with a n etch-ro u g hened su rface, resembl i n g i n effect a su perfi n e fi l e .
The p o l i sh i ng action is so d e l i cate that no scratches a re left, yet corroded m ate ri a l w i l l be
removed ra p i d l y and thorou g h ly . The flexi b i l ity of the too l ensu res the cl ea n i n g of the
actual poi nts of contact; someti mes an ord i na ry fi le ca n n ot reach the actua l p o i nts o f
contact beca use o f obstructi on from some oth er p a rt o f t h e re lay.
F i n e si lve r contacts should not be cleaned with knives, fi les or a b rasive paper o r cl oth .
K n i ves o r files may leave scratches that i n crease a rci n g and d eterioratio n of t h e co ntacts.
Abrasive paper or cloth may leave m i n ute p a rticles of i nsu lati ng a b rasive mate r i a l i n the
contracts, and thus p revent closi n g .
T h e b u rn i sh i ng tool d escri bed above can b e obta i n ed from facto ry.
TAR G ET AND S E A L- I N U N IT
For tri p coi ls operati ng on cu rrents ra n g i ng from 0.2 u p to 2 .0 a m peres at the m i n i m u m
control voltage, set the ta rget and sea l - i n ta p p l u g i n the 0. 2-am pere ta p .
F o r tri p coi l s operati ng on cu rrents ran g i n g fro m 2 .0 u p to 3 0 a m peres a t th e m i n i m u m
contro l voltage, p lace the targ et and sea l - i n ta p p l u g i n the 2 .0-am pere ta p .
The t a p p l u g is t h e screw hold i n g the rig ht-hand stationary contact o f t h e sea l - i n el e m e nt.
To ch a n g e t h e ta p setti n g , fi rst remove the con necti ng p l u g . T h e n , ta ke a screw from the
left-hand stati o n a ry contact and place it i n the desi red ta p . Next, remove th e screw fro m
th e oth e r, u n d es i red, ta p, and pl ace it i n the left-hand contact. Th is p roced u re is necessa ry
to p revent the rig ht-hand stati onary contact from g etti ng out of adj u stm e nt.
s h o u l d be i n
not both
h i g h er ta p va l u e, a nd AC pickup wi l l be i ncreased .
VO LTA G E S ETTI N G
T h e vo lta g e at wh ich t h e contacts operate may b e changed b y cha n g i n g t h e position o f t h e
ta p p l u g i n t h e ta p block at the top of rel ays such a s the IAV5 1 A, IAV52A, IAV53A, IAV53 B ,
I A V 5 3 D, I A V 5 3 K, IAV5 3 L,and IAV5 3 N w h i ch h a ve ta p p ed co i l s .
adjustment i s from 5 5 to 1 40 volts o n the 1 1 5 volt ratin gs, 7 0 to 1 40 vo lts o n th e 1 99 volt
rati ngs, 1 1 0 to 280 vo lts on the 208, 230 a nd 240 volt rati ngs, and 220 to 560 volts on the
460 volt rati ngs.
The p i cku p of the relay for any voltage ta p is adj usted by means of a spri n g -adj u sti n g
ri n g (see Fig u re 1 5) . The ring may be tu rned by i n serting a tool i n the n otches a ro u nd the
ed g e . By tu rn i ng the r i n g , the operating voltage of the re l a y may be b ro u g ht i nto
a g reement with the ta p setting empl oyed if, for so me reason, th is adj u stment has been
d istu rbed . The adj ustment a lso perm its any desi red setting between the va rious ta ps. The
relay is adj usted at the factory to operate from any time-d i a l positi o n s at a m i n i m u m
volta g e with i n five percent ( 5 % ) of the ta p setti ng fo r the relays with the ta p ped co i ls,
m e ntioned above . The relays reset at 90 % or more of the operati n g va l u e on a l l the
overvoltage re lays. Operati ng voltage for the overvoltage relays fo r a g iven ta p sett i n g is
the m i n i m u m voltage at w h i ch the contacts j ust m a ke.
G E H - 1 8 1 4

SE RVICI NG AN D ADJ U STM E NTS

ta ps at the sa me time, as pickup for d i rect cu rrent (DC) wi l l be the
1 2
Screws
T h e ra n g e o f t h i s