No Taps - GE IAV51A Instructions Manual

The Type IAV 5 1 A i s an overvo l tage re l ay wi th s i ngl e-c i rcu i t c l os i ng contacts wh i ch cl ose when the
vol tage i ncreases to pi ckup val ue as set on the tap bl ock .
determi ned by the setti ng of the time d i a l a t the top of the shaft .
rel ay are shown i n Fi g . 12 .
The IAV52A re l ay i s simi l ar i n every respect to the IAV51 A rel ay except that i t has add i ti onal contacts
for c l os i ng a second c i rcui t .
The IAV53A re l ay i s an u nder-and overvol tage rel ay wi th doub l e - th row contacts .
cl ose as the vol tage i ncreases to some predetermi ned val ue .
decreases to some l ower val u e .
characteri s ti cs are shown i n Fig . 13 .
The Type I AV53B rel ay di ffers from the Type I AV53A rel ay i n that i t does not have seal - i n el ements .
Time-vol tage characteri s ti cs are shown i n F i g . 13 .
The Type IAV53C rel ay i s s i m i l ar to the Type IAV53A rel ay except that there are no taps on the coi l .
The rel ay i s adj us ted to cl os e i ts ri g h t contacts i n 1 0 seconds when the vol tage i s reduced from 58 percent
rated vol tage to zero vol tag e ; wi th th i s cal i bra tion th e rel ay cl oses i ts l e ft contacts in a pproxi mate l y
1 0 seconds when the vol tage i s i ncreased from 5 8 percent of rated vol tage to rated vol tage .
are used connec ted l i ne- to-ground so that under normal cond i ti ons the rel ay recei ves 58 percen t of rated
ph ase-to-phase vol tage and both rel ay contacts are open .
grounded , the rel ay vol tage goes to zero and the r i g h t-hand contacts c l ose i n 1 0 second s .
other two phases are grounded , the rel ay vol tage i ncreases to rated vol tage and th e l eft-hand contacts
cl ose i n approximate l y 1 0 seconds .
The IAV53D rel ay i s s i mi l a r to the Type I AV53B rel ay except th at i t has a sh orter time cu rve .
vol tage characteri stics are shown i n Fi g . 1 4 .
The Type I AV53K i s simi l ar t o t he Type I AV53A , IAV53L t o IAV53B , I AV53M to I AV53C a n d I AV53N toiAV53D.
Al l four rel ays a re in t he doubl e -end case wi th contacts connected between the upper and l ower bl ocks and
operat i ng coi l s connected to both bl ocks .
the connecti ng pl ugs are removed and subs equently rei n se rted wi th the rel ay i n the reset po s i t i on , i . e . ,
c i rcu i t open i n g contacts cl osed .
i n pl ace before the contact c i rcu i t s a re compl eted .
* c i rcu i t s , and Fi g . 1 1 for external connecti on s .
These rel ays are of the i nducti on d i s k construc ti on .
coi l on a l ami nated U-magnet .
ci rcui t when i t touch es the s ta ti onary contact or contacts .
to g i ve the proper contact c l os i ng vol tag e , and i ts motion i s retarded by perma nent magnets acti ng on th e
d i s k to g i ve th e correct time del ay .
There i s a seal - i n uni t mounted to the l e ft of the sh aft as shown i n Fi g . 15 .
i n seri es and i ts contacts i n paral l el wi th the ma i n contacts s uch that when the ma i n contacts cl ose , the
* I nd i cates rev i s i on
TABLE I I I
RELAY VOLTAGE
TYPES RAT I NG
25 - CYCLE BURDE N S ( Can ' t . )
IAV53A 1 1 5
&
IAV53B
1 1 5
IAV53C
••Mi n i mum pi ckup vol ts .
CHARACTERIST I CS
The time-vol tage character i s ti cs are shown i n F i g . 12 .
Between th ese two vol tage val ues both contacts are open .
The purpose of thi s i s to avo i d fa l se tri ppi n g of the brea ker i f
I n sert i on of e i ther pl ug causes the rel ay to pi c k u p ; bot h pl u gs must be
The d i s k shaft carri es the movi ng contact , wh i ch compl etes the tri p or al arm
GEH - 1 81 4
(
Can ' t . )
POWER
TAP ** VOLT-
AMPS FACTOR
S ETT I NG
0 . 32
1 40 ., 7
1 . 3 0 . 30
1 20
2 . 9 0 . 30
1 0 5
9 3 4 . 2 0 . 30
82 5 . 3 0 . 32
70 7 . 5 0 . 34
0 . 34
64 9 . 5
55 1 2 . 9 0 . 39

NO TAPS

4 . 2 0 . 38
The ti me del ay i n cl os i ng the conta c ts i s
The time-vol tage character i s ti cs o f th i s
The r i gh t-hand contacts c l ose when the vol tage
I f the phase to wh i ch th e re l ay i s connected i s
See i nternal connect ions Fi g . 6-8 for co i l and contact
CONSTRUCT! ON
The d i s k i s ac tua ted by a poten ti a l operati ng
The di sk shaft i s res trai ned by a spi ra l spri ng
6
WATTS
0 . 5
0 . 7
0 . 9
1 . 3
1 . 7
2 . 6
3 . 3
5 . 0
1 . 6
The l eft-hand contacts
T i me-vol tage
These rel ays
I f e i ther of th e
Time ­
T h i s uni t has i ts coi l