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The indicating instantaneous trip contacts will close
30 amperes at 250 volts dc and will carry this current
long enough to trip a breaker.
3.2
Indicating Contactor Switch (ICS)
a. The indicating contactor switch has two
taps that provide a pickup setting of 0.2 or 2
amperes. To change taps requires connect-
ing the lead located in front of the tap block
to the desired setting by means of a screw
connection.
b. Trip Circuit Constants
0.2 amperes tap. . . . . . . 6.5 ohms dc
2.0 amperes tap. . . . . . . 0.15 ohms dc
3.3
ac Auxiliary Switch (ACS)
a. Each of the following ACS units is available
in the Hi-Lo Line of relays.
4.
INSTALLATION
The relays should be mounted on switchboard pan-
els or their equivalent in a location free from dirt,
moisture, excessive vibration and heat. Mount the
relay vertically by means of the mounting stud for
projection mounting or by means of the four mount-
ing holes on the flange for the semiflush mounting.
ASC/VOLTAGE
ACS
CURRENT
UNIT
RANGE
0.15
0.2-0.38
0.5
0.75-1.5
1.0
1.5-3.0
Notes: (1) This is the voltage range which will operate the ACS coil
only.
(2) When connected as a current switch in series with a full
rated voltage relay or trip coil.
Energy Requirements
BURDEN IN
ACS
VOLT-AMPERES
UNIT
AT MINIMUM
SETTINGS
0.15
4.5
0.5
4.5
1.0
4.5
Courtesy of NationalSwitchgear.com
resistance
resistance
MINIMUM
RECOMMENDED
DROP
SUPPLY
RANGE (1)
VOLTAGE (2)
40-76
–
14-27
208
6.8-14
120
THERMAL CAPACITY
AMPERE RATING (COIL)
1 SECOND CONTINUOUS
4.5
0.16
18.0
0.63
44.0
1.60
Either the stud or the mounting screws may be uti-
lized for grounding the relay. The electrical connec-
tions may be made directly to the terminals by
means of screws for steel panel mounting or to the
terminal stud furnished with the relay for thick panel
mounting. The terminal stud may be easily removed
or inserted by locking two nuts on the stud and then
turning the proper nut with a wrench.
For detail information on the FT case refer to
I.L. 41-076.
5.
SETTINGS
5.1
CO Unit
The overcurrent unit setting can be defined by tap
setting and time dial position or by tap setting and a
specified time of operation at some current multiple
of the tap setting (e.g. 4 tap setting, 2 time dial posi-
tion or 4 tap setting, 0.6 seconds at 6 times tap value
current). The tap setting is the minimum current re-
quired to make the disc move.
To provide selective circuit breaker operation, a min-
imum coordinating time of 0.3 seconds plus circuit
breaker time is recommended between the relay be-
ing set and the relays with which coordination is to
be effected.
The screw on the terminal plate above the time dial
makes connections to various turns on the operating
coil. By placing this screw in the various terminal
plate holes, the relay will respond to multiples of tap
value currents in accordance with the various typical
time-current curves.
!
CAUTION
Since the tap block screw on both the CO unit
and IIT unit carries operating current, be sure
that the screws are turned tight.
In order to avoid opening current transformer
circuits when changing taps under load, the re-
lay must be first removed from the case. Chassis
operating shorting switches on the case will
short the secondary of the current transformer.
The taps should then be changed with the relay
outside of the case and then re-inserted into the
case.
I.L. 41-100J
3
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