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Type MG-6 Multi-Contact Auxiliary Relay
the total of special make and break contacts limited to
six. The locations of the make and break contacts for
any combination of these special contacts are shown
in Figure 3. This figure indicates the physical location
of the contacts in the relay, and can be used in con-
junction with the internal schematic diagram for the
type of case involved to determine the corresponding
terminal locations.
2.3. BASE AND STATIONARY CONTACT
The stationary contacts (Figure 1, Item 2) are on six
legs located at the top and bottom of the base. The
stationary contact brackets are connected directly to
the terminal inserts by means of long screws passing
through brass tubes. This method allows a tight con-
nection without compressing the base material. The
contact bracket is held against its seat by means of a
spring ring which is compressed between shoulders
in the base and on the hexagonal terminal insert.
2.4. BASE AND COVER
The base and cover are molded of a phenolic and in
several versions. The molded versions are:
• Rear-connect projection mount
• Rear-connect semi-flush mount
• Front connect
The relay is also available in the FT-22 case. See IL
41-076 for additional details.
2.5. LATCH
The self-reset assembly is the standard build of the
relay. The electrical reset assembly (as shown in Fig-
ure 2) is optional and can be supplied with any of the
configurations. The upper half of the figure is the re-
set assembly viewed from the front. The lower half of
the figure is a bottom view which shows the latch
screw (in the main armature) for the relay in an ener-
gized position, and the reset armature is free to be
moved to the right by the tension spring until the hard-
ened latch plate on the reset armature rests against
the tip of the latch screw. When the operating coil is
de-energized, the latch screw will move slightly so
that its shoulder rests on the edge of the latch plate.
When the reset coil is energized its armature moves
to the left, thus permitting the main armature to return
to its open position. Pressing the reset push rod,
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which extends through the cover stud, will also re-
lease the latch through the medium of the reset lever
shown in the figure.
2.6. CUTOFF CONTACT
The cutoff contact assembly (Figure 1, Item 9) is lo-
cated at the side of the operate coil and is used to
achieve a faster than normal relay operation.
In some applications of the Type MG-6 relay having
the latch and electrical reset, it may be desirable to
have the operating and reset coils de-energized auto-
matically as soon as their functions have been per-
formed. With the reset coil, de-energization can be
accomplished by connecting the coil through one of
the relay's "make" contacts. An auxiliary contact is re-
quired to open the operating coil circuit. This contact,
when provided, is located on the lower right side of
the relay, and is held in position by the terminal screw
to which the right coil lead ordinarily connects. The
coil lead is connected to the moving contact of the
auxiliary contact assembly, and the end of the station-
ary contact bracket is in contact with the head of the
terminal screw. The auxiliary contact is closed when
the main armature is open. When the armature ap-
proaches the closed position, the spring on the mold-
ed insulation block snaps off the roller and causes the
contacts to open and interrupt the operating coil cur-
rent. When this auxiliary contact is used, a weight is
added at the lower end of the armature to increase its
mass and stabilize contact action. The auxiliary con-
tact will interrupt currents to five times rated coil cur-
rents.
3.0 OPERATION
The MG-6 relay is an electromagnetic type solenoid
device with six independent contacts. When the coil
is energized, the armature is attracted to the lamina-
tion stack thereby operating the moving contacts. Op-
eration is single mode with a make or break function
that can be supplied with either a self or a latching re-
set. The duty cycle may be from extremely intermit-
tent to continuous energization.
41-753.1M
5
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