Bulletin No 30072-013-10
Reference No 278AS
Table 1 Field Modification Kits, Class 9999
Push button, Start-Stop
Push button, On-Off
Selector switch, Hand-Off-Auto
Selector switch, On-Off
Red pilot light SP15R
? For 120 V only, for other voltages refer to Class 9001 Type KP units.
A melting alloy overload relay is supplied as standard with provisions for three thermal units. The
contact unit (item 6 in Figure 1) of the melting alloy overload relay is available with a normally-open
or normally-closed isolated alarm contact in addition to the standard normally-closed contact. The
contact unit with alarm circuit contacts can be installed in the field (refer to Table 5).
Non-temperature compensated bimetallic overload relays are available as an optional feature: Form
B 1 has provisions for two thermal units, Form B2 has provisions for three thermal units. Ambient-
temperature compensated bimetallic overload relays are also available as an optional feature (Form
B has provisions for three thermal units).
A SPDT contact is supplied as standard on all Type S bimetallic overload relays. The N. O. contact
can be used in an alarm circuit and must be wired on the same polarity as the N. C. Contact.
Contacts are not replaceable. In order to directly replace a bimetallic overload relay, the appropriate
part number listed on the parts list should be used.
These overload relays are not designed for field repair and should not be disassembled.
Use copper wire only on device power and control terminals. Pressure wire power terminals are
suitable for wire sizes #14-8, solid or stranded. Pressure wire control terminals are suitable for wire
sizes #16-12, solid or stranded.
Contacts are not harmed by discoloration and slight pitting. Do not file contacts, as it wastes
contact material. Replacement is necessary only when the contact has worn thin. Replacement
contacts for starters or contactors are available as kits. Older from Table 5.
Replacement contacts and springs for the poster pole kits only are contained in a Class 9998 Type
SL22 kit. One kit is required for each N. O. or N. C. Contact.
It is unnecessary to remove any wiring to inspect or replace the contacts. To inspect or replace
contacts, loosen the two captive screws (item C in Figure 1) holding the contact actuator to the
contact block. Lift the contact actuator to expose the contacts.
Disconnect all power before manually operating equipment.
Manual operation with power on car, cause contact arcing and unexpected energization of
load, resulting in personal injury or equipment damage.
Manual operation of contactors and starters may be accomplished by pushing the contact carrier
down with a screwdriver. There is a slot provided on the coil cover that is suitable for this use.
To remove the coil, loosen the two captive cover screws (item A in Figure 1). Disconnect wires from
the coil terminals and remove the cover. Remove and disassemble the magnet, coil and armature
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