GE IAC77B Manual page 9

The one second thermal ratings are listed in Table IV.
0
For ratings of less than one second, the rating may be calculated according to the formula
where T is the time in seconds that the current flows.
The continuous ratings of the time overcurrent units are shown in Table V.
INSTANTANEOUS UNIT
The instantaneous unit has a double wound coil for operation on either one of two ranges.
obtained in the lower range (series connected) is doubled, .within ±3�when the unit is connected for high
range operation (parallel connected) .
The instantaneous unit has a continuous rating of 1.5 times minimum setting or 2 5 amperes whichever
is smaller. Example:
has a continuous rating of 3. 0 amperes, and when connected for high range operation (4.0 -16. 0 amperes)
has a continuous rating of 6.0 amperes.
are shown i n Table VI.
TIME OVE RCUR RENT UNIT
(AMPS)
0. 5 - 4. 0
1.5 - 1 2. 0
0. 5 - 4. 0 AW RANGE
TAP 0. 5
0. 6 0. 7
RATIN G 3.5
3.7 4. 0
Af1>
1. 5 - 12. 0
RANGE
T AP
1. 5 2.0 2. 5
RATING 9 .5 10. 5 1L5
AMP
2. 0 - 15.0 RANGE
TAP 2. 0 2.5 3.0
RATING 10. 0 1 1. 0 12. 0
The 2. 0 -16. 0 ampere instantaneous unit when set on the low range (2.0-8. 0 amperes)
The continuous and one second ratings for the instantaneous unit
GEK-3 40 55
TABLE IV
1-SEC. RATIN G
(AMPS)
125. 0
15.625
260:0
260.0 67 , 600
I
TABLE V
0.8
1. 0 1.2 1.5
4.5
5.0 5. 5 6.0
3.0 4.0
125" 1 4.0
4.0 5.0 6. 0 7.0
13.0 15. 0 17.0 18.0
5
K
2.0
2.5 3. 0 4. 0
7.0
8. 0 9.0
10. 0
7.0 8. 0
10.0 12.0
1 0
19.0
8.
20.0 20.0
8. 0 10. 0 1 2. 0 15. 0
19. 0 20.0 20.0 20. 0
Any setting