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GLK—26437
The relay mechan i sin is niouritod
in a
s tee
framework ca led the cradle and is a coinpi ate unit w
ti
a 1
leads terminated at the inner block.
This cradle is heir
1 firmly in the
case
wit
1 a latch at both top and
bottom and by a guide pin at the back of the case.
The connecting nlug, besides maKing tne electrical con
nections between the respective blocks of the cradle and case, also locks the latch in place.
The cover.
which is drawn to the case by thumbscrews, holds the connecting plugs in place.
The target reset mechanism
is a part of the cover aeinu1y.
The relay case is suitable for either semi-flush or surface mounting on all panels up to two inches
thick and appropriate nardware is available.
Hoae.er, panel thickness must be indicated on the relay order
to insure teat proper hardware will be included.
A separate testing plug can be inserted in place of the connecting plug to test the relay in place on
the panel either fro,n its own source of current and voltage, or from other sources.
Or the relay can be
drawn out and replaced by another which has been tested in the laboratory.
Figs. 1 and 2 shown the relay removed from its drawout case with all major components identifi-.
Symbols used to identify circuit components are the same as those which appear on the internal connection
diagram in Fig. 13.
The relay includes major subassembly elements:
The lower element includes the M 1 unit with associated circuit components.
Adjustable reactor X 1
,
used
in setting angle of maximum torque, and rheostat R
1 1
, used in setting basic minimum reach
can be
adjusted from the front of the relay.
Transactor
Tfl-l
,
with tap block for selecting the basic minimum
reach of M 1
,
is mounted on the rear of the element with tap screws accessible from the front.
2.
The middle element includes the N 2 unit with its associated circuit components.
Rheostats R
1 2 for
setting basic minimum reach and R
2 2 for setting angle of maximum torque are accessible from tFie
front of the relay.
A terminal block with links for selecting the basic minimum reach is mounted at
the rear of the element.
GENERAL ELECTRICAL TESTS
DRAWOUT RELAYS GENERAL
Since all drawout relays in service operate in their cases, it is recommended tha.. they be tested in
their cases or an equivalent steel case.
In this way any magnetic effects of the enclosure will be
accurately duplicated during testing.
A relay may be tested without removing it from the panel by using a
12XLA13A test plug.
This plug makes connections only with the relay and does not disturb any shorting bars
in the case.
Of course, the 12XLA1?A test plug may also be used.
Although this test plug allows greater
testing flexibility, it also requires shorting jumpers and the exercise of greater care since connections
are made to both the relay and the external circuitry.
POWER REQUIREMENTS GENERAL
All alternating current operated devices are affected by frequency.
Since non-sinusoidal waveforms can
be analyzed as a fundamental frequency plus harmonics of the fundamental frequency, it follows that
alternating current devices (relays) will be affected by the applied waveform.
Therefore, in order to properly test alternating current relays it is essential to use a sine wave
of current and/or voltage.
The purity of the sine wave (i.e. its freedom from harmonics) cannot be
expressed as a finite number for any particular relay, however, any relay using tuned circuits, R-L or RC
networks, or saturating electromagnets (such as time-overcurrent relays) wou'd be essentially affected by
non-sinusoidal wave forms.
Similarly, relays requiring d-c control power should be tested using d-c and not full wave rectified
power.
Unless the rectified uppiy is well filtered, many relays will not operate properly due to the dips
in tie rectified power.
Zoner diodes, for example, can turn of during these dips,
As a general rule the
d-c source should not contain more than 5 percent ripple.
RECEIVING, HANDLING AND STORAGE
most relays, when miot included as a part of a control tanel
,
will he shipped in cartons designed to
protect
trier"
against damage.
Irnediately upon receipt of a relay, examine it for any damage substained in
transit.
If injury or damage resulting from rough handling is evident, file a damage claim at once with t
transportation compaly and promptly notify the neareast General Electric Apparatus Sales Office.
Reasonable sare s:cijld be exercised in unpacking the relay in order that none of the parts are injured
or
the
ddjustrnentc disturbed.
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