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APPLICATION
The a-c tripping unit is used in Type lAC relays
where a reliable direct-current tripping source is
not available and it is necessary to trip the breaker
from
the current-transformer secondary.
RATINGS
The a-c tripping
unit
has a continuous rating of
five amperes but will operate on a minimum current
of 3.5 amperes.
They should be used with three
ampere trip coils. The contacts of these units will
transfer current transformer secondary current up
to
100
amperes. For applications where the second
ary current exceeds 100 amperes, the
REAllB
relay,
Time Overcurrent Relays Type IAC
GEH-1753
which has contacts rated 200 amperes, can be used
in conjunction with lAC overcurrent relays.
The
REAllB is not mounted inside the lAC case.
BURDENS
Burdens of the REA unit are given in the
following table:
Frequency
Amp
Impedance
PF
Volt-
in Ohms
Amperes
60
5
0.49
0.80
12.2
50
5
0.33
0.85
8.4
25
5
0.23
0.62
5.8
RECEIVING, HANDLING AND STORAGE
These relays, when not included as a part of a
control panel, will be shipped in cartons designed
to �rotect them against damage. Immediately upon
receipt of the relay, an examination should be made
for any damage sustained during shipment.
If
injury or damage resulting from rough handling is
evident, a claim should be filed at once with the
transportation company and the nearest Sales Office
of the General Electric Company notified promptly.
Reasonable care should be exercised in un-
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2
6
INTERNAL CONNECTIONS !FRONT
VI
[W) ·=sHORT FINGER
Fig. 11. (K-6209658-10) Internal Connections fo�
the Type IAC51A Relay
(Front View).
packing the relay in order that none of the parts are
injured or the adjustments disturbed.
If
the relays are not to be installed immediately,
they should be stored
in
their original cartons in a
place that is free from moisture, dust, and metallic
chips.
Foreign matter collected on the outside of
the case may find its way inside when the cover is
removed and cause trouble in the operation of the
relay.
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INDUCTION
UNIT
INSTANT
UNIT
5
6
SHORT FINGER
Fig.
12. (K-6209661 [11) Internal Connec tions for
the Type IAC51B Relay (Front View)
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