ABB MG-6 Manual

R
!CAUTION
Before putting the relay into service, remove
all blocking which may have been inserted for
the purpose of securing the parts during ship-
ment, make sure that all moving parts operate
freely, inspect the contacts to see that they
are clean and close properly, and operate the
relay to check the settings and electrical con-
nections.
1.0 APPLICATION
The Type MG-6 relay is designed for applications
where several independent circuits may be energized
or de-energized upon the operation of a single prima-
ry relay contact or where the capacity of the primary
relay contact is inadequate for the energy required. In
certain applications these relays may be used directly
as primary relays. The stationary contacts can be re-
versed so that either circuit opening or circuit closing
service is readily attained. It is not necessary to pre-
determine the relay’s circuit arrangements. If the relay
has a dc operate coil, a small increase in spring ten-
sion may be required; this will be covered under sec-
tion 7, “ADJUSTMENTS and MAINTENANCE”.
In the usual application of the relay, the armature re-
sets when the operate coil is de-energized. However,
the relays can be supplied with a latching mechanism
that holds the armature in the operate position until
the latch is tripped: either by hand or electrically.
An operate coil cutoff contact can be supplied with
the electric-reset type, where an intermittent duty
coil is required for faster than normal operation, but
where the operating coil circuit will be energized
continuously. An operating coil, rated at 19% of
supply rating may be applied, with a maximum duty
of 10,000 operations (e.g., 24 volt coil on a 125 volt
dc circuit).
2.0 CONSTRUCTION
The Type MG-6 relay (Figure 1) consists of five ma-
jor assemblies mounted in several base and cover
configurations. The assemblies are as follows:
• Operating electromagnet
• Armature and moving contact
• Base and stationary contact
• Latch (Optional)
• Coil Cutoff Contact (Optional)
2.1. OPERATING ELECTROMAGNET
The operating electromagnet, located at the lower
end of the relay as shown in Figure 1, is comprised
of the operate coil (Figure 1. Item 8) and a
U-shaped lamination stack. The coil utilizes one leg
of the stack as its core. This leg is slotted at the out-
er end to receive the copper lag loops used to ob-
tain quiet ac operation. For a dc operated coil, an
iron plate, rather than lag loops, is used to improve
41-753.1M
ABB Automation Inc.
Substation Automation and Protection Division
Coral Springs, FL 33065
Type MG-6 Multi-Contact
Auxiliary Relay
Instruction Leaflet
Effective: December 1999
Supersedes 41-753.1L Dated November 1992
All possible contingencies which may arise during installation, operation or maintenance, and all details and
variations of this equipment do not purport to be covered by these instructions. If further information is desired
by purchaser regarding this particular installation, operation of maintenance of this equipment, the local ABB
Power T&D Company Inc. representative should be contacted.
( ) Denotes Change Since Previous Issue
ABB
ABBABB
ABB
I
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41-753.1M Type MG-6 Multi-Contact Auxiliary Relay
2
performance. The inner end of the other leg of the
stack is shaped so the armature restraining spring
can be attached.
2.2. ARMATURE AND MOVING CONTACT
The steel armature has projecting sections at the
sides, near the center, which act as knife-edge bear-
ings and rest on supports that are a part of the mold-
ed base. A stud attached to the core leg of the lami-
nation stack, extends through a hole in the lower end
of the armature. A self-locking stop-nut on the outer
end of the stud is used to limit and adjust the travel
of the armature in the de-energized direction.
The upper end of the armature has an adjustment
screw to which one end of the armature restraining
spring is attached. In both the hand and electrically
reset versions of the relay, a latch screw is mounted
at the extreme end of the armature. For the self-reset
relays, the adjustment screw is replaced by a set
screw which serves to slightly separate the locking
plate (see Figure 1) from the armature. Located be-
tween the spring adjustment screw and the latch
(set) screw is a third screw which, when tightened,
applies pressure to the former screws and effectively
locks them in place.
The type MG-6 relay for ac can be used with any
combination of contacts, but the dc relay can have
up to four circuit-opening contacts with the normal
operating spring adjustment. With more than four the
operating spring should be adjusted to give the cor-
rect back contact follow.
The moving contact fingers are mounted on a mold-
ed insulation plate attached to the armature. Silver
contact buttons are on both sides of the fingers so
they may be used as either a circuit-opening or a cir-
cuit-closing contact. The fingers are assembled on
guide pins, between two springs so that a definite
spring compression and contact wipe is assured for
either the contact-closing or the contact-opening
conditions. Flexible leads are connected to the con-
tact fingers. The armature assembly has contact fin-
gers located above and below the bearing points so
Figure 1: Front view (Cover Omitted) and Side View of the MG-6 Electric and Hand Reset Relay in Molded Case.
1–Reset Push Rod, 2–Stationary Contact, 3–Moving Contact,
4–Moving Contact Spring Assembly, 5–Latch Adjustment Screw,
6–Adjusting Screw for Armature Spring Tension, 7–Reset Coil,
8–Operating Coil, 9–Optional Operating Coil Cut-off Contact
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Type MG-6 Multi-Contact Auxiliary Relay 41-753.1M
3
the weight is partially balanced about the bearings
leaving less chance for severe shocks to move the ar-
mature. The corresponding stationary contact assem-
bly, with its large silver button contacts, can be in-
stalled to close with the moving contacts when the
armature is in either the energized or de-energized
position.
In certain applications of the type MG-6, it may be de-
sirable to have one or more of the contacts close be-
fore other contacts on the same relay open. A special
armature assembly is required to obtain such opera-
tion, and the number of special make and break con-
tacts desired must be known when the relay is built.
The special moving contacts have longer follow than
the standard contacts and greater armature spring
tension is required for full deflection of the break con-
tacts. Consequently, it is preferable to limit the num-
ber 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, with
Figure 2: Detail Views of the Latch and Electrical Reset of
the Type MG-6 Relay
Sub 1
Figure 3: Contact Positions for Combinations of
Make-Before-Break Contacts
CONTACT
POS. A
CONTACT
POS. E
CONTACT
POS. F
CONTACT
POS. B
CONTACT
POS. C
CONTACT
POS. D
STATIONARY BREAK CONTACT ASSEMBLIES
ASSY REVERSE CONTACT AT POSITION
0
*1 A
*2 A B
*3ABF
*4ABEF
5BCE
6CD
7BE
8AF
9ABC
10 A D F
11 A B C D
12 A B C D E
13 A B D E F
14 B
15 B D
16 B C
17 B C D
18 B C D F
19 C D
20 D
21AEF
22 F B
23 A D
24 A B C D E F
25BEF
26 F
27 B D E
* Also used for Make-Before-Break operation. Bend all
Make-Before-Break Stationary Contacts equally toward
moving contacts to obtain make approx. .0625"
contact travel before break.
9660A79
NOT FOUND
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41-753.1M Type MG-6 Multi-Contact Auxiliary Relay
4
Figure 4: Internal Schematic of the Type MG-6 Relay,
Without Electrical Reset, in Molded Case. Figure 5: Internal Schematic of the Type MG-6 Relay, With Electrical Reset, in Molded Case.
Sub 9
4D1072 Sub 7 4D1076
Figure 6: Internal Schematic of the Type MG-6 Relay,
Without Electrical Reset, in FT-22 Case. Figure 7: Internal Schematic of the Type MG-6 Relay, With Electrical Reset, in FT-22 Case.
Sub 1
183A223 Sub 2 183A222
STATIONARY
CONTACT
MOVING
CONTACT
OPERATING
COIL
TERMINAL
STATIONARY
CONTACTS MAY
BE REVERSED
TO CLOSE THE
CIRCUIT WHEN
THE COIL IS
DEMAGNETIZED
STANDARD
LOCATIONS OF
NC CONTACTS,
IF SET AT
THE FACTORY FRONT VIEW
1234
5
78
910
11 12
13 C16
D
AEFB
6
NO POSITION
1
2
3
4 ABEF
ABF
A
B
A
1234
5
78
910
11 12
13 16
6
14 15
ALL STATIONARY
CONTACTS MAY BE
REVERSED TO CHANGE
CONTACTS TO
NORMALLY CLOSED.
OPERATING
COIL
TERMINAL
COIL
INTERRUPTING
CONTACT
(WHEN USED)
RESET COIL
MOVING
CONTACT
STATIONARY
CONTACT
FRONT VIEW
12345678910
11
12
13
14
15
16
17
18
19
20
MG
0
MG
MGMG
MG
MG
MG
TOP RIGHT
RIGHT CENTER
OPERATING COIL
BOTTOM RIGHT
TEST SWITCH
TERMINAL
BOTTOM LEFT
LEFT CENTER
TOP LEFT
11
12
13
14
15
16
17
18
19
20
MG
0
MG
MG
MG
MG
MG
MG
12345678910
MG
R
TOP LEFT
LEFT CENTER
BOTTOM LEFT
TOP RIGHT
RIGHT CENTER
RESET COIL
OPERATING COIL
BOTTOM SHUNT
COIL INTERRUPTING
CONTACT
(WHEN USED)
TEST SWITCH
TERMINAL
INTERNAL
SCHEMATIC
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Type MG-6 Multi-Contact Auxiliary Relay 41-753.1M
5
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.
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,
I
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41-753.1M Type MG-6 Multi-Contact Auxiliary Relay
6
4.0 CHARACTERISTICS
Standards Meets all of the following as applicable:
ANSI C37.90
IEC 255
UL STD-508
Operating Time Normal: ac - approximately
0.033 sec
dc - approximately
0.083 sec
If faster operation is desired and if the application re-
quires only intermittent energization of the relay, the
operating coils may be energized at higher than rat-
ed voltage. (1)Twice rated voltage will give an oper-
ating time of approximately .017 cycle on ac, and the
coil will stand this voltage safely for over two minutes
if 60 hertz or 4 minutes if 25 hertz. (2) The time of the
dc relay can be reduced to slightly over .017 cycle if
the coil is energized at five times rated voltage. The
coil will stand this voltage for one minute. If faster
time is desired on a dc relay which must be ener-
gized continuously, the use of a low voltage coil with
a series resistor will reduce the time. With 10% of the
line voltage across the relay coil and the balance
across a series resistor, the reduced inductance of
the circuit results in an operating time of approxi-
mately .033 seconds. The time of operation may be
reduced to approximately .017 second by applying 4
or 5 times rated dc voltage to the coils through the
coil interrupting contact.
Frequency dc, 50 or 60 hertz
(Specify when ordering)
Dielectric Withstand 1000 volts plus twice the opera-
tional Voltage for one minute
Relay Pickup 80% of rated voltage
60% of dc relay without interrupt-
ing contact rating.
Relay Latch Reset 70% of rating momentarily applied
Contact Rating Make: 30 Amp @ 575 volts ac for
1 Min.
12 Amp continuous
Break: Non-inductive loads only
30 Amp @ 115 volts ac
20 Amp @ 230 volts ac
15 Amp @ 460 volts ac
10 Amp @ 575 volts ac
30 Amp @ 12 volts dc
15 Amp @ 24 volts dc
10 Amp @ 32 volts dc
8 Amp @ 48 volts dc
3 Amp @ 125 volts dc
1 Amp @ 250 volts dc
Burdens:
Reset coils are for intermittent duty only and should
not be energized longer than one-half minute.
Temperature Range -20 to +55 degrees C (operating)
-40 to +70 degrees C (storage)
5.0 SETTINGS
The relays are shipped from the factory correctly ad-
justed for armature travel and for contact follow and
pressure. No adjustments should be necessary. All
contacts are assembled for circuit closing (making)
operation unless special arrangements have been
ordered. To convert to circuit-opening (breaking)
operation, loosen the screws for the stationary con-
tact bracket, turn the bracket over and tighten the
screw. Check the contact follow. It may be neces-
sary to slightly bend the bracket(s). Refer to section
7.4.1 for details. On dc relays it is recommended that
no more than four contacts be reversed. This is to
assure that correct contact pressure and travel are
maintained.
6.0 INSTALLATION
The MG-6 relay should be mounted on switchboard
panels or their equivalent in a location free from dirt,
dust, moisture, excessive vibration and heat. Mount
the relay vertically by means of the rear mounting
stud or studs for projection mounting, four mounting
holes on the frame for semi-flush mounting, four
mounting holes in the backplate for the front-con-
nected style relay or for the FT-22 case mounted re-
lay. The electrical connections may be made directly
to the terminals by means of screws for steel panel
mounting or to the terminal studs (furnished on re-
quest) for thick panel mounting. The terminal studs
may be easily inserted or removed by locking two
Operating Coil
at rated Voltage Frequency (Hertz)
Closed Gap Open Gap
Watts Volt- Amps Watts Volt- Amps
25
50
60
dc
dc
6.8
9.8
12
7.8 cold
6.5 hot
23
31
37
19.6
17.4
17.6
7.8 cold
6.5 hot
53
78
92
Reset Coils at
rated voltage 25 50
60
dc
48
46
84
66 cold
51.6
58.2
104.5
52
57
96
68 cold
54
63.8
112.8
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Type MG-6 Multi-Contact Auxiliary Relay 41-753.1M
7
nuts on the stud and then turning the proper nut with
a wrench. Relay grounding is accomplished by using
a mounting screw or the lower mounting stud. In the
case of the front-connected with cover, a lug is provid-
ed adjacent to the upper mounting hole for device
grounding.
For detailed FT case information, refer to I.L. 41-076.
7.0 ADJUSTMENTS AND
MAINTENANCE
The proper adjustments to insure correct operation of
the relay have been made at the factory and the relay
should not require readjustment after receipt by the
customer. If any of the adjustments or the contact
configuration have been changed or the relay disas-
sembled, the instructions below should be followed.
The relay should be mounted in a normal vertical op-
erating position for all of these checks. Reference Fig-
ures 1 & 2 and Section 5,SETTINGS, above for part
identification and contact information.
7.1. ACCEPTANCE CHECK
The following checks are recommended to ensure
that the relay is in proper working order:
Pickup: 80 percent of rating
Make contacts: Operate simultaneously
Break contacts: Operate simultaneously
7.2. ARMATURE
7.2.1. Armature Stop Adjustment Nut
The armature stop adjustment nut should be set to
3/8 inches with the armature held against the electro-
magnet. For those relays having an interrupt contact,
the measurement is 7/16 inches. The flat on the nut
should be parallel with the armature. The hole in the
armature must not touch the stop nut stud for either
the extreme right or the extreme left position of the ar-
mature in its bearings. Adjust the position of the coil
should the stud be touching either side.
7.2.2. Armature Spring (Preliminary adjustment)
When adjusting the armature spring tension, the lock-
ing screw for the spring adjusting screw is loosened,
and this adjusting screw is turned (inward, to reduce
the spring tension) until the spring barely holds the ar-
mature against the stop nut. The relay must be in its
normal vertical position when this adjustment is
made, with all contacts assembled as circuit-closing.
The armature spring should then be tightened by turn-
ing the adjusting screw 4 turns counter-clockwise for
ac relays or 2 turns for dc relays, and the locking
screws should be tightened.
7.2.3. Armature Spring (Final adjustments)
If the relay is dc operated, turn the spring adjuster
counterclockwise 2 turns. This does not apply to those
relays with four or more break contacts. If the relay is
ac operated and has less than six break contacts, turn
the spring adjuster counterclockwise 4 turns. For the
dc relays with four or more break contacts and the ac
relay with six break contacts, turn the spring adjuster
counterclockwise only enough for the armature to hit
the stop nut. Tighten locking screw on non-latching re-
lays. See section on latch assemblies for information
on latching relays.
OPERATING DATA FOR CONTINUOUSLY RATED AUXILIARY RELAYS
Rating
Operating Coil Reset Coil
dc
Resistance
(Ohms)
±10%
@25 Degree C
Must Pickup
(Volts)
80% of Rating
dc
Resistance
(Ohms)
±° 10%
@25 Degree C
1 amp dc
2 amps dc
3 amps dc
4 amps dc
5 amps dc
4.8
1.0
.4
.24
.15
6 volts dc
12 volts dc
24 volts dc
32 volts dc
4.8
19
75
132
4.8 volts
9.6 volts
19.2 volts
25.6 volts
.53
2.12
8.5
13.9
48 volts dc
62.5 volts dc
125 volts dc
250 volts dc
310
530
2000
8200
38 volts
50 volts
100 volts
200 volts
34
56
222
890
115 volts, 60 Hz
208 volts, 60 Hz
230 volts, 60 Hz
460 volts, 60 Hz
575 volts, 60 Hz
19
67
75
305
495
92 volts
166 volts
184 volts
368 volts
460 volts
91
322
364
1445
2208
115 volts, 50 Hz
230 volts, 50 Hz
460 volts, 50 Hz
575 volts, 50 Hz
26
105
465
660
92 volts
184 volts
368 volts
460 volts
138
550
2200
3500
* Reset Coil Intermittent Rating 100% for 60 Seconds
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41-753.1M Type MG-6 Multi-Contact Auxiliary Relay
8
Figure 9: Outline and Drilling Plan for the Type MG-6 Relay in the Front Connected Molded Case. See Internal Schematic
For Terminals Supplied.For Reference Only.
* Sub 9
04D1122
Figure 8: Outline and Drilling Plan for the Type MG-6 Relay in the Rear Connected Molded Case. For Reference Only.
Sub 6
184A370
* Denotes Change since previoius issue
2.75
-
(
69.85
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1.938
(
49.22
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NOTE
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DIMENSIONS
IN
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ARE
MILLIMETER
EQUIVALENTS
4.125
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1.375
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3.437
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Type MG-6 Multi-Contact Auxiliary Relay 41-753.1M
9
7.3. MOVING CONTACT FINGERS
When a moving contact finger has been removed
from its guide pin and is to be reassembled, the coil
springs on either side of the finger must be replaced
correctly. Select the stronger spring and place it on
the closing side of the contact finger. The stronger
spring can be selected by placing the two springs on
a flat surface and compressing them. Pick the stron-
ger of the two.
7.4. CONTACTS
7.4.1. Contact Follow
The follow of the moving contact fingers should be
3/32” for the make contacts and 1/16” for the break
contacts, measured at the contacts. This can be
checked more conveniently by measuring the travel of
the lower edge of the armature after the contacts
touch. This should be approximately 1/8” for themake
contacts and 3/32” for the break contacts. In case
moving contact fingers have been removed from their
guide pins, it is important that the coil springs on the
two sides of the fingers be replaced correctly. The
springs which are compressed by circuit-closing con-
tacts are approximately three times as strong as the
ones compressed by circuit-opening contacts and
thus they can be readily distinguished. The positions
of the two springs are reversed at the two ends of the
relay.
7.4.2. Special Purpose Contacts
When special contacts have been supplied for
make-before-break applications, all corresponding
stationary contacts must be bent equally toward their
respective moving contact to obtain “make” at the
point where the “break” moving contact has approxi-
mately a 1/16 inch follow before parting from its sta-
tionary contact.
7.4.3. Cutoff Contact
If the relay is provided with a coil interrupting contact,
the following points must be observed to assure sat-
isfactory operation. With the relay in its normal oper-
ating position and the armature shifted to the extreme
right, align the armature “snap” spring so that it is at
least 1/64 inch in from the right-hand edge of the mov-
ing contact spring. With an .030 inch gap between the
armature and the lower pole face of the electromag-
net, adjust the bracket by means of the adjusting
screw, until the snap spring just passes the roller. The
latch screw should be adjusted so that with the arma-
ture in the latched position and the operating coil
deenergized, the gap between the armature and the
lower pole face of the electromagnet is .010 to .015
inch. With the armature in this position the coil inter-
rupting contact should be open at least 3/64 inch.
7.4.4. Contact Cleaning
All contacts should be periodically cleaned. A contact
burnisher Style # 182A836H01 is recommended for
this purpose. The use of abrasive material for clean-
ing contacts is not recommended, because of the
danger of embedding small particles in the face of the
soft silver and therefore impairing the contact.
7.5. LATCH ASSEMBLIES
On latching type relays the latch screw is adjusted so
that with the armature latched and the operating coil
de-energized, there will be a gap of 0.020 ±0.005
inches between the electromagnet pole face and the
raised section of the armature striking the pole face.
Following this adjustment, tighten the locking screw
securely.
There is a small amount of clearance between the ar-
mature and its supporting posts, and in order to insure
proper operation, allowance must be made for this in
the following manner. With the armature held against
its left-hand support and nearly closed, the latch
spring or reset armature should be moved to the left
as far as it will go by means of the hand reset. To as-
sure that the latch will always release the armature
the resulting space between the latch and the latch
screw should be at least .010 inch, and should not be
more than about 1/64”. This should also be checked
electrically if electrical reset is provided. Some
change of this gap can be made by loosening the
mounting screws in the relay base and moving the
latch support in the desired direction. The gap also
can be changed by loosening the two screws which
hold the moving contact insulation block to the arma-
ture and shifting the armature in the desired direction.
On electrical reset relays, the tension of the spring
which draws the reset armature toward the latch
screw must be adjusted if these parts are being reas-
Courtesy of NationalSwitchgear.com

41-753.1M Type MG-6 Multi-Contact Auxiliary Relay
10
sembled. The locking screw (Figure 2) is screwed
out until its head clears the head of the adjusting
screw. The main armature is then held completely
closed and against its right-hand support, and the
latch spring tension adjusting screw is turned until
the latch barely touches the stop projecting from the
center of the latch screw. Then the latch spring ten-
sion should be increased by turning the screw clock-
wise 9 turns, and the locking screw should be tight-
ened.
If either the core nut of the electrical reset assembly
or the screws which mount its armature have been
loosened, the relative positions of the core and
plunger may shift sufficiently to cause the plunger to
strike on the side of the conical core opening. To as-
sure correct alignment of these parts, .042 diameter
holes are provided through the center of the core and
about 1/16” deep in the center of the plunger. After
tightening the core nut, a close fitting pin should be
inserted through the core and into the plunger. With
the pin in place, and plunger pressed firmly against
the core, and the mounting end of the armature cen-
trally located with respect to the electromagnet, the
two armature mounting screws should be tightened.
The pin then should be removed.
A small amount of silicone oil is supplied at the fac-
tory to the polished and hardened surfaces of the
latch screw and the latch plate to minimize wear and
as protection against corrosion. Oil should be reap-
plied after any cleaning and reassembling of these
parts, and it is desirable also to renew this at the reg-
ular maintenance periods
7.6. SPECIAL DROPOUT COILS
If an ac relay is to be dropped out by shorting the coil,
a high wattage resistor must be placed in series with
the coil to handle the current during the time the coil
is shorted. An alternate method is to reduce the ar-
mature spring tension to approximately 1-1/2 turns
and reduce the follow of the stationary make contact
to 1/16 inches. This can be accomplished by bend-
ing the stationary contact. With this reduced tension,
the number of break contacts is limited to two. Be-
cause of the low relay impedance with armature
open as compared to the impedance with armature
closed, it is not advantageous to use a resistor in se-
ries with a coil rated at less than line voltage as in the
case of dc applications. If the coil is to only be short-
ed momentarily or if a higher wattage consumption is
not objectionable, it may not be necessary to reduce
the spring tension or contact follow. The contact and
spring adjustments example specified above is a 60
hertz MG-6 relay with a voltage rating equal to line
voltage and can be used with a series resistor that
handles 90 watts when placed directly across the
line.
I
Courtesy of NationalSwitchgear.com

Type MG-6 Multi-Contact Auxiliary Relay 41-753.1M
11
Figure 10. Outline and Drilling Plan for the Molded Semi-Flush Case. For Reference Only.
Sub 8
183A817
Figure 11: Outline and Drilling Plan for the Front Connected with Cover Case. For Reference Only.
Sub 1
9656A20
.
125
.
166
.
250
(
3.2
)
'
(
4.8
J
‘
(
6.4
>
CL
SHARP
TO
.
219
4.108
m R
MAX
(
106.4
)
2.375
2.781
2.094
TYP
TERM
.
HARDWARE
(
70.6
)
(
603
)
(
53.2
)
h
I
(
T
.
.
_
_
_
i
i
—
_
J
i
_
—
—
m
i
IftD
J
SPACER
7375
(
187.3
)
6.125
(
155.6
)
6.750
3
(
171.5
)
5.938
(
150.8
)
T
9
3.063
WIDE
'
WASHER
IGTY
.
2
)
(
77.8
)
2344
2.969
D
(
59.5
)
3375
(
75.4
)
(
65.7
)
.
250
(
6.4
)
)
—
i
.
r
—
—
4
*
2
PANEL
—
OPENING
FIG
.
2
5513
531
MAX
SPECIAL
MOUNTING
FOR
.
250
PANELS
(
134.9
)
(
WITH
RESET
ROD
)
(
135
)
.
FOR
.
125
3.234
.
PANELS
(
0
Z
1
)
FOR
.
188
3.172
PANELS
(
80.6
)
FOR
.
250
3.109
PANEL
'
S
(
79
)
1063
v
(
27
)
\
1969
(
OTHERWISE
SAME
AS
FIG
.
1
)
.
125
gg
R
IF
SLOTTED
(
50
)
3.938
(
100
)
OR
4.688
.
250
DIA
HOLE
4
HOLES
(
119.1
)
DIMENSIONS
IN
INCHES
(
DIMENSIONS
IN
MILLIMETERS
)
16
TERM
.
SCREWS
-
.
190
-
32
4
MTG
.
SCREWS
.
190
-
32
FIG
.
1
TERMINAL
NUMBERS
(
REF
)
GND
.
LEAD
4
O
•
e
-
f
©
)
o
7.438
O
O
6
5
(
188.93
)
O
O
8
ALT
.
7
POS
.
•
.
281
OK
)
0
'
*
(
4
HOLES
)
6.750
o
D
10
9
(
171.45
)
C
O
12
11
3.375
(
85.73
)
iTE
n
O
15
16
13
14
5.563
(
141.30
)
(
MAX
.
WITH
RESET
ROD
)
.
344
WHEN
USED
(
8.74
)
2.375
.
344
(
60.33
)
(
8.74
)
4.750
(
120.65
)
5.438
DIMENSIONS
IN
INCHES
(
138.13
)
(
DIMENSIONS
IN
MILLIMETERS
)
.
190
-
32
(
4.83
)
.
250
-
2 0
(
6.35
)
16
TERM
.
SCREWS
2
MTG
.
SCREWS
Courtesy of NationalSwitchgear.com

41-753.1M Type MG-6 Multi-Contact Auxiliary Relay
12
AB
CD
EF
Location of Contact Positions (Front View)
Contact Positions
ABCDEF
Number of Special
Make Contacts 1 2
3
4
5X
X
X
X
X
X
X
X
X
X
X
X
XX X
Contact Positions
ABCDEF
Number of Special
Break Contacts 1 2
3
X
X
XX XX
Location Chart for Special Make-Before-Break Contacts
MG-6 ENCODE/DECODE TABLE
Relay Contact Positions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A B C D E F
Positions . . . . . . . . . . . . . . . 1 2 3 4 5 6 7 8 9 10 11 12 13 14
RelayStyleNo(example)..M GF 7 3 Y 7 3 MMMMMM
Pos 3: Enclosure (A-F) A = Semi-Flush Mounting
Rear Connected
B = Projection Mounting
Rear Connected
C = Surface Mounting without cover
Front Connected
D = FT-22 (Flexitest)
F = Surface Mounting with cover
Front Connected
Pos 4 & 5: Operate Coil Rating Code (01-99) See Table 1 (Coil Code)
Pos 6: Coil Interrupting Contact (CIC) N = No (CIC is not used)
Y = Yes (CIC is used)
Pos 7 & 8: Reset Coil Rating Code (01-99) See Table 1 (Coil Code)
Pos 9-14: Contact Arrangement B = Standard break
(B,M,1,2) M = Standard make
1 = Special break (make before break) (see below)
2 = Special make (make before break) (see below)
I
I
Courtesy of NationalSwitchgear.com

Type MG-6 Multi-Contact Auxiliary Relay 41-753.1M
13
TABLE 1
OPERATE AND RESET COIL CODES
ac dc
CODE RATING FREQ CODE RATING FREQ
01 12 V 60 Hz 59* 5 A dc
02 12 V 50 Hz 60* 4 A dc
03 24 V 60 Hz 61* 3 A dc
04 24 V 50 Hz 62* 2 A dc
05 48 V 60 Hz 63* 1 A dc
06 48 V 50 Hz 64 12 V dc
07 48 V 25 Hz 65 24 V dc
08 115 V 60 Hz 66* 28 V dc
09 115 V 50 Hz 67 32 V dc
10 208 V 60 Hz 68* 36 V dc
11 230 V 60 Hz 69* 38 V dc
12* 230 V 50 Hz 70 48 V dc
13 460 V 60 Hz 71 62 V dc
14 575 V 60 Hz 72* 79 V dc
15 575 V 50 Hz 73 125 V dc
16 460 V 25 Hz 74 200 V dc
17* 575 V 25 Hz 75* 220 V dc
18 12 V 25 Hz 76 250 V dc
19 24 V 25 Hz 77 6 V dc
20 115 V 25 Hz 78* 40 V dc
21 230 V 25 Hz 79* 0.1 A dc
22 460 V 50 Hz 80 500 V dc
23 60 V 60 Hz 81 to 99 are not used
24 120 V 60 Hz
25** 220 V 50 Hz
26 208 v 50 Hz
27* 92 V 60 Hz
28* 5 A 60 Hz
29 to 58 are not used
* = Not available for reset coil.
** = Not available for operate coil.
REF:
Operate coil style = 632F619G (Code No.)
Reset coil style = 1461C19G (Code No.)
Table 1 = 1503B34, Sub 11
NOTE: For 57.5 – 58 Volts 50 Hz
Use 60 Volts 60 Hz
I
Courtesy of NationalSwitchgear.com

41-753.1M Type MG-6 Multi-Contact Auxiliary Relay
14
THIS SPACE RESERVED FOR NOTES
Courtesy of NationalSwitchgear.com

Type MG-6 Multi-Contact Auxiliary Relay 41-753.1M
15
THIS SPACE RESERVED FOR NOTES
Courtesy of NationalSwitchgear.com

41-753.1M Type MG-6 Multi-Contact Auxiliary Relay
Printed in U.S.A.
ABB Automation Inc.
4300 Coral Ridge Drive
Coral Springs Florida 33065
TEL: [phone]
FAX: [phone]
visit our website at www.abbus.com/papd
ABB
ABBABB
ABB
Figure 11. Outline and Drilling Plan for the Type MG-6 Relay in Type FT-22 Case.
*Sub 14
183A158
* Denotes Change since previoius issue
PANEL
DRILLING
AND
CUTOUT
FOR
SEMI
-
FLUSH MTG
.
CASE
OUTLINE
1.594
(
40.49
)
-
6.063
(
154.00
)
.
563
14.30
)
5.563
(
141.30
)
2.781
(
70.64
)
^
.
250
DIA
,
(
6.35
)
4
HOLES
FOR
.
190
-
32
MTG
.
SCREWS
r
T
5.219
(
132.56
)
ir
—
*
9.688
(
246.08
)
9.063
(
230
,
20
)
3
-
CASE
$
\
T
10.438
(
265.13
)
3
-
L
<
L
4.531
—
(
115.09
)
4.844
(
123.04
)
LARGE
INTERNAL
AND EXTERNAL
TOOTH
WASHER
.
'
190
-
32
SCREW
i
I
*
«
|
SEMI
-
FLUSH MTG
.
3
.
188
(
80.98
)
.
125
R
(
3.18
)
SMALL
EXTERNAL
TOOTH
WASHER
-
2.938
(
74.63
)
5.875
(
149.23
)
PROJECTION
MTG
.
6.375
—
(
161.93
)
PANEL
PANEL
LOCATION
TERMINAL AND
MTG
.
DETAILS
PANEL
DRILLING
OR CUTOUT FOR
PROJECTION
MTG
.
(
FRONT
VIEW
)
FOR
PROJECTION
MTG
.
NOTE
PILOT
PLATE PANEL
PROJECTION
HARDWARE
MUST
BE
ORDERED
SEPARATELY
.
T
\
1.813
(
46.05
CASE
SPACERS
FOR
THIN
PANELS
^
-
5
/
16
-
18
SCREW
(
FOR
THICK
PANELS
T
USE
5
/
16
-
18
STUDS
)
INTERNAL
-
EXTERNAL
TOOTH
WASHERS
.
190
-
32
HEX
WASHER
HEAD
SCREW
OR
.
190
-
32
FILLISTER
HEAD
SCREW
FLAT
WASHER
&
LOCK
WASHER
.
5941
(
15.09
.
563
DIA
.
(
25.4
)
2.688
*
(
68
,
28
) (
14.29
)
2
HOLES
1.344
—
(
34.14
)
5.375
Z
3
+
.
0161.397
)
.
-
0
(
136.53
)
250
t
(
6
,
350
)
1.031
—
(
26
,
19
)
1
.
344
-
(
34.14
)
.
375
R
(
9.53
)
TYP
.
r
^
:
iS
i
T
.
594
(
15.09
)
_ _
JL
.
- -
1.0
(
25.4
)
T
FOR
THICK PANELS
USE
.
190
-
32
STUDS
z
*
3
1
7
9
5
4
-
1
813
(
46.05
)
PANEL
2.0
.
641
DIA
.
J
(
16.28
)
I
(
50.8
)
1
2
l
,
I
TERMINAL
NUMBER
.
516
(
13.11
)
.
750
DIA
.
—
(
19.05
)
20
HOLES
OR
2
CUTOUTS
-
1.031
(
26.19
)
TYP
.
Courtesy of NationalSwitchgear.com