Rockwell Automation 509 Full Voltage Starter - Size 8 (Series B Construction) - Manual

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BULLETIN
505 z 509
FULL VOLTAGE STARTERS z SIZE 8
SERIES B CONSTRUCTION
CONTACTS
- The weld-resistant, double break
contacts are of cadmium oxide silver. Square, solid
seating prevents twisting or sliding motion and
extends contact life.
These contacts should not be filed or dressed.
Removal of the contact block cover makes the
mounting screws for the front stationary contact
assembly accessible. The contacts are brazed on
heavy copper parts which are attached to the
stationary contact block by two screws. Remove
these screws and extract the front stationary contact
assembly by depressing the movable contact. To
take out the rear stationary contact assembly, simply
remove the coil cover and slide out the cross bar
assembly, which includes the following items: cross
bar, push rod assemblies, and the magnet armature
assembly. With the cross bar assembly out, the
mounting screws for the rear stationary contacts
accessible and they can be removed along with the
arc quenchers which are attached to the stationary
contact block.
The movable contacts are carried in stainless steel
cages which in turn are mounted in cavities in the
molded portion of the cross bar. This cage assembly
is held in place by a screw which can be loosened
from the underside. Therefore, to replace movable
contacts, it is only necessary to replace the
assembly with a new assembly.
STATIONARY CONTACT BLOCK -
The hot-
molded contact block has a high degree of
mechanical strength and dimensional accuracy.
Material resists arc tracking and arc blast damage.
Separate arc chambers contain efficient metal arc
quenchers.
To detach the stationary contact block, remove the
contact block cover which is held in place by two
captive screws. Then take out the two contact block
screws which hold the stationary contact block to the
base assembly. The contact block can now be
detached.
CROSS BAR ASSEMBLY
-
The portion of the
cross bar carrying the movable contacts is molded,
but the movable contacts are carried in stainless
steel cages which in turn are mounted in cavities in
the molded portion. The push rod assemblies are
attached to the cross bar molding with screws which
clamp together two sides of a dovetail joint to make
a very rigid connection. The push rod assemblies
are molded with insert studs at the lower end which
are used to fasten the lower cross member which is
a steel plate going through the armature iron. Make
certain that upon replacement the push rod
assemblies lie against the shoulder of the cross
bar.
The cross bar is available less the movable
contacts. However, if the movable contacts are
needed, they can be purchased as a completed
assembly. The push rod assemblies are obtainable
as separate items. The magnet armature assembly
can be disassembled and its parts procured
separately. Part numbers for each item can be found
on Page 3 and 4.
To remove the cross bar assembly: first, detach
contact block cover whish is held in place by two
captive screws; second, loosen the screws on the
Knowledgebase Technotes ID # Q18318, can be found at http://support.rockwellautomation.com/