Renewal Parts - ABB MG-6 Instruction Leaflet

MG-6 Multi-Contact Auxiliary Relay
screw and the latch plate in order to minimize wear
and protect against corrosion. Oil should be reapplied
after any cleaning and reassembling of these parts,
and it's also recommended to renew oil application at
regular maintenance periods.
6.6 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
armature spring tension to approximately 1-1/2 turns
and reduce the follow of the stationary make contact
to 1/16". This can be accomplished by bending the
stationary contact. With this reduced tension, the
number of break contacts is limited to two. Because
of the low relay impedance with the armature open
as compared to the impedance with the armature
closed, it is not advantageous to use a resistor in
series with a coil rated less than line voltage, as in the
case of dc applications. If the coil is only to be shorted
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 for a
60 Hz 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.
7.0 CALIBRAtION
Calibrating the relay is only necessary if the relay
has been taken apart for repairs or the adjustments
disturbed. This procedure should not be used until it is
apparent that the relay is not in proper working order.
To calibrate the relay, see Section 6.1 ACCEPTANCE
CHECK.
ABB
7.1 ROutINe MAINteNANCe
All relays should be inspected periodically and the
time of operation should be checked at least once
every year or at such other time intervals as may be
dictated by experience to be suitable to the particular
application.
All contacts should be cleaned periodically. A contact
burnishing tool, Style # 182A836H01 is recommended
for this purpose. The use of abrasive material for
cleaning contacts is not recommended because of
the danger of embedding small particles in the face of
the soft silver and thus impairing the contact.
For relays with latching assemblies, a small amount
of silicone oil is applied at the factory to the polished
and hardened surfaces of the latch screw and the
latch plate in order to minimize wear and protect
against corrosion. Oil should be reapplied after any
cleaning and reassembling of these parts and it's
also recommended to renew oil application at regular
maintenance periods

8.0 ReNeWAL pARts

Repair work can be done most satisfactorily at the
factory. However, interchangeable parts can be
furnished to customers who are equipped for doing
repair work. When ordering parts, always give the
complete information found on the Relay Nameplate.
IL 41-753.1 N
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