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IL 41-753.1 N
2.2.1 special Contacts (make-before-break)
In certain applications of the MG-6 relay, it may
desirable to have one or more of the contacts close
before other contacts on the same relay open
(make-before-break). A special armature assembly
is required to obtain such operation and the number
of special make and break contacts desired must be
known when the relay is ordered.
The special moving contacts have longer follow than
the standard contacts and greater armature spring
tension is required for full deflection of the break
contacts. Consequently, it is preferable to limit the
number of special break contacts to two. A maximum
of three may be used, although the increased armature
spring tension needed may raise the minimum pick-
up voltage above the standard value.
As many as five contacts may be special make
contacts at one time, and all six contacts may be a
combination of special makes and special breaks.
The location of the make and break contacts for all
possible combinations of these special contacts are
shown in Table 1. This table indicates the physical
location of the contacts in the relay and can be used
in conjunction with the internal schematic diagram
(for the type of case involved) to determine the
corresponding terminal locations.
2.3 Base and stationary Contacts
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
connection 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 Latch
The self-reset assembly is the standard build of
the relay. The electrical reset assembly (as shown
in. Figure 2) is optional and can be supplied in any
case configuration. The upper half of the figure
shows the reset assembly viewed from the front
of the relay. The lower half of the figure (looking in
from the bottom of the relay) shows a sectional view
of the reset assembly with the latch screw (of the
main armature) in a de-energized position. The reset
4
MG-6 Multi-Contact Auxiliary Relay
table 1
Designated position of special Contacts
special "Breaks"
(max 3 allowed)
A
C
A
C
A
C
A
C
A
A
B
C
A
B
C
A
B
C
A
B
C
A
B
F
C
A
B
F
C
A
B
F
C
Example:
A
B
C
Contact positions "C", "D", and "E" will make or close before
contact positions "A" and "B" open. The remaining (non-special)
relay contact "F" can be designated as a standard make or break.
armature is free to be moved to the right by the reset
armature tension spring until the hardened latch plate
on the reset armature almost rests against the latch
screw. When the operating coil is energized, the latch
screw will move slightly so that its shoulder comes to
rest 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 which extends
through the cover stud will also release the latch by
way of the reset lever, as shown in Figure 2.
FRONT
VIEW
special "Makes"
(complement Special Breaks)
D
D
E
D
E
F
B
C
D
E
D
D
E
D
E
F
D
D
E
D
E
F
ABB
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