ABB MG-6 Instruction Leaflet

ABB ABB ABB ABB
Effective: December 1999
Supersedes 41-753.1L Dated November 1992
( ) Denotes Change Since Previous Issue
R
!
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
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.
Courtesy of NationalSwitchgear.com
ABB Automation Inc.
Substation Automation and Protection Division
Coral Springs, FL 33065
CAUTION
Type MG-6 Multi-Contact
Auxiliary Relay
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
Instruction Leaflet
41-753.1M