D Escri Ption - GE IAV51A Instructions Manual

Type IAV re lays a re sing le-phase, voltage-operated, i n d u ction-d isk rel ays with adj usta b l e

time d e l ay. The IAV5 1 A and IAV52A a re overvoltage rel ays. The IAV53A, B , C, D, K, L, M,

and N a re over- and u ndervoltage relays.

These I AV relays a re used for protection agai nst a lternating-cu rrent (AC) overvoltage, fo r

perm i ssive control and tri p p i n g of automatic equi pme nt, a nd for g ro u n d d etection on

eq u i pment and feeders.

F i g u re 1 0 shows the ty p i ca l co n n ecti o ns fo r t h e a p p l i cati o n of a n IAV5 1 A relay fo r

protection a g a i nst overvoltage i n a th ree-p hase system . The IAV52A ca n be u sed fo r

a p p l i cati ons req u i ri n g two tri p-output circuits. The operati ng-ti me cha racte ristics fo r these

rel ays a re shown in Fig u re 1 2 .

F ig u re 1 1 shows the co n n ecti on d i a g ram for IAV53 over- and u ndervoltage rel ays. The

IAV53A has sepa rate normal ly-open and norma l ly-closed contacts with sea l-i n u n its on

each contact.

A typ i ca l appl ication for perm i ssive co ntro l and tri p p i n g of a u to m atic

eq u i pment wou ld uti l ize the normal ly-open contact to enable the mach i n e breaker-closi n g

circu it w h e n normal mach i n e voltage is p resent, a n d t h e n o r m a l l y-cl osed contact to

operate the mach i ne brea ker-tri p circu it for u ndervo ltage con d itions. The operati n g -time

cha racteristic fo r the IAV53A, IAV53B, IAV5 3 K and IAV 5 3 L rel ays a re shown in F i g u re 1 3 .

The IAV53 D and IAV53N ti me characteristics are shown i n Fig u re 1 4.

The IAV53C is desig ned for g round-fa u lt protection, and would no rma l l y be a ppl ied with a

phase-to-n e utra l con n ection, g iving 58% of rated voltage. The re lay is adj usted to h ave a

1 0-second operati n g time for either a g round on the con n ected ph ase (0 volt operates the

UV contact), or a g ro u n d on another phase (rated volts operates the OV co i l ) .

These instructions do not purport to cover all details o r variations i n equipment nor provide for every

possible contingency to be met in connection with installation, operation or maintenance.

inf ormation be desired or should particular problems arise which are not covered suf ficiently f or the purchaser's

p urposes, the matter should be referred to the General Electric Company.

To the extent required the products described herein meet applicable ANSI, IEEE and NEMA

standards; but no such ass urance is given with respect to local codes and ordinances because they vary greatly.

G E H- 1 81 4

VOLTAG E R E LAYS

IAV 5 1 A

IAV52A

IAV 53A, 538, 53C, 530, 53K, 53L, 5 3 M ,

D E SCRIPTI O N

APPLICATION

TYP E S

and

3

53N

S ho uld further