Sta Ndards A N D Testing - GE Power Break II Manual

Application
Standards And Testing
Power Break® I I circuit breakers a re U L Listed in accordance
with Sta ndard U L 489. This standard requires the breaker to
meet or exceed endura nce and i nterrupting criteria. Power
Break I I breakers a re designed and tested to exceed these
req uirements.
UL 489 requirements for end urance capabi lity without cur­
rent (mechanical endurance) vary with frame ratings. For
exa mple, for a n 800-amp frame, the UL req uirement is 3000
operations; and for a 4000-am p fra me, only 1 100 opera­
tions. All Power Break II breakers are designed to exceed this
requirement by meeti ng a minimum of 10,000 mechanical
operations.
Ul Test Proced u res
Extracted from U L Sta ndard 489, current edition.
The fol lowi ng information b riefly describes the types of tests
Power Break I I insulated case circuit breakers, rated 800
through 4000 a m peres, must successfully pass.
1. Calibration: Tested at 200%, and 135% at 25°
200%, an 800A breaker must trip in 2 to 30 minutes de­
pending on the cu rrent rating. At 135%, all sizes (larger
than 50 a m peres) must trip within 2 hours.
50 operations making and breaking six times
2. Overload:
rated current at rated minimum voltage, 0.45-0.5 0
power factor for 8 0 0 and 1600A frame sizes; 2000 and
2 500A fram es, 2 5 operations at six time rated current­
and, 3000 and 4000A frames, 3 operations at six time
rated current plus 25 operations at two times rated cur­
rent. Tests a re cond ucted at one operation per min ute,
(make and break), but may be done in groups of five
operations with 15-minute delay between g roups.
Overload test is conducted i n a metal enclosure rep­
resenting the minimum size e nclosure for which the
b reaker is suitable. No electrical or mechanical break­
down is perm itted and a 30-ampere fuse, connected
from the metal enclosure to the line lead least likely to
a rc to the enclosure, must not rupture.
3.
Repeat 200% ca libration test.
4. Tem perature Test: The circuit b reaker after overload
i s outfitted with 4 ft . minimum of rated copper cable
per pole, line and load end, and rated current is passed
through the brea ker which is not i n a n enclosure. After
tem peratures have sta bilized, the temperature rise on
the cables at the connection to the breaker wiring ter­
minals must not exceed 50'C rise, ( 7 5 ' C total in a 2 5 ' C
room ambient), and t h e breaker must not trip. Cables a re
sized as shown in Table 43.1. When the copper bus bars
a re used instead of cable for 1600-4000A breakers, they
a re sized per Ta ble 43.2.
Endura nce: The breaker must complete an endurance
5.
test (1) making and brea king rated current at rated volt­
age, .7 5-.80 lagging power factor and (2) additional no
38
load (mechanical) on-off operations per Table 38.1. The
g rou nd-fault fuse described in item 2 above must not
rupture.
The rate of operation is one per minute except the 3000
and 4000A electrical test m ay be in g roups of five with a
delay in between after cond ucting the fi rst 10 operations
at one per minute.
Table 38.1
Number of End urance Test Cycles
Frame
Size lAmps)
800
1600
2000
2500
3000
4000
c.
6.
Repeat 200% ca libration test.
7.
I nterrupting a bility (short-circuit)
At
Vac (all Power Break II brea kers): Each pole of the 3-pole
u n1t must complete a n "opening" ope ratio n (0) and a
"close-open" operatio n (CO) of short-circuit current
(single-phase) in Table 38.2 at rated voltage. An "0" and
"CO" operation using a l l three poles ("common" 3-phase
tests) is also required o n the same device used for previ­
ous the tests in items 1-6.
�
Short-circuit test a re acceptable if:
a) there is no e lectrical or mechanical breakdown·
b) the g round fuse has not opened;
c) the conductor i nsulation is not d a maged;
d) there is conti nuity in the closed position at rated
voltage; and,
e) a cotton pad covering a ny vent openings i n the
enclosure has not ignited.
Short-circuit test a re cond ucted with rated cable sizes (or bus
for 1600A and larger breakers) using a maximum of four feet
on the l i n e side and a maximum of 10 inches on load side for
3-pole tests and four feet on load side for single-pole tests.
Table 38.2
Short-Circuit Levels
Frame Size
(Amps)
800
1600
2000
2500
3000
4000
CD Circuit power factor may be . 2 5-.30.
Number of Cycles of Operation
Without Current
With Cu rrent
500 3000
500 2000
2000
500
2000
500
400 1 100
400 1 100
for devices rated 600
Power 3-Pole Circuit Breaker -Available
Factor, Lagging Short-circuit Current Sym. Amp
1-Pole, 1-Phase
45-.50 8660
.25-.30 14000
140oo CD
. 1 5-.20
2oooo CD
. 1 5-.20
. 1 5-.20 25000
30000
. 1 5-.20
Total
3 500
2500
2500
2500
1500
1500
'
3-Pole, 3-Phase
10000
20000
25000
30000
35000
45000