Installation Manual

8901 E. PLEASANT VAL LEY ROAD
INDEPENDENCE, OHIO 44131-5508
TELEPHONE: [phone] • FAX: [phone]
E-MAIL: [e-mail]
• WEB: www.avtronencoders.com
INDUSTRIAL AUTOMATION, INC.
SHAFT GROUNDING
KIT INSTRUCTIONS
for
AV850
DESCRIPTION
These shaft grounding kits are designed to be installed with
AV850 encoders and are intended for the reduction of motor
bearing problems caused by shaft currents. For other Avtron en-
coders, shaft grounding options are available factory installed for
the reduction of encoder and motor bearing problems caused by
motor shaft currents.
Under certain operating conditions, a motor shaft can be subjected
to shaft currents that seek the lowest resistance path to ground.
If this path is through bearings it can result in shortened bearing
life. The shaft grounding option is intended to provide a lower re-
sistance path to divert shaft currents away from bearings.
The shaft grounding kit consists of a gasket sealed brush holder,
a silver graphite brush, a shaft extender, a wire lug, and stainless
steel mounting hardware. Use the wire lug with a ground wire to
provide a low resistance ground connection.
WARNING
All maintenance and installation procedures listed below
must be performed by qualified personnel, and with the mo-
tor turned OFF to prevent possible injury or death.
INSTRUCTIONS
FOR ADDING BRUSH GROUNDING KITS TO AV850 SERIES ENCOD-
ERS WHEN USED WITH GE MOTORS: CD180AT, CD210AT, CD320AT
1. Remove all oil, grease, and dirt from the threaded hole in the
center of the motor shaft.
2. Install the motor shaft adapter and rotor per AV850 instruc-
tions with the following exception: Do NOT apply loctite to the
standard mounting screw.
3. Remove standard mounting screw, apply threadlocker to ex-
tender shaft (Item 1) threads, and install as shown in Figure 2.
4. Verify rotor runout is still acceptable.
5. Assemble encoder stator housing to motor per encoder
instructions. Remove and discard standard coverplate,
if present.
6a. For rotor style “G,” the brush holder is preassembled.
6b. For grounding kits purchased separately:
I. Assemble brush holder and gasket to coverplate and
attach to stator housing using hardware supplied.
II. Assemble remainder of shaft grounding kit. (Refer to
Figures 1 and 2.)
FOR ADDING BRUSH GROUNDING KITS TO AV850 SERIES ENCOD-
ERS WHEN USED WITH GE MOTORS: CD360AT, CD400AT, CD500AT,
CD505, CD680, CD6000, CD4300 THRU CD4700, CD5400, CD6400,
CD6500, CD7500, CD7600, CD8500, CD8600
1. Install stator adapter, shaft adapter, and rotor following
AV850 instructions.
2. Apply threadlocker (Item 17) to socket head cap screw &
install extender shaft (Item 1), as shown in Figure 3.
3. Assemble encoder stator housing to stator adapter per en-
coder instructions. Remove and discard standard coverplate,
if present.
4a. For rotor style “G,” the brush holder is preassembled.
4b. For grounding kits purchased separately:
I. Assemble brush holder and gasket (Items 2 and 3) to
coverplate and attach to stator housing using hardware
supplied.
II. Assemble remainder of shaft grounding kit. (Refer to
Figures 1 and 3.)
MAINTENANCE
Inspection
A new brush is 5/8" long. The brush should be replaced after
it has worn 3/8" maximum (see Figure 2 - Shaft Grounding Kit
Assembly). The brush should be inspected after 1 year to de-
termine the wear rate for each installation. Replace brush if it is
worn to a length of 1/4".
Cleaning
The brush holder cavity should be cleaned every time the brush
is removed for inspection. Refer to Figure 2 - Shaft Grounding Kit
Assembly, and clean as follows:
1. Remove the cap screw and brush.
2. Remove pipe plug from the bottom of the brush holder.
WARNING
Use safety goggles when using compressed air to prevent
possible eye injuries.
3. Use dry compressed air applied through the brush opening
to blow out any worn brush material residue through the bot-
tom of the brush holder. An optional method is to suction the
brush residue using a vacuum cleaner.
KIT APPLICATION
MOTOR
FRAME
SHAFT SIZE
KIT PART NO.
AV850
CD180-320AT
CD360AT
CD400AT
CD500AT
CD505
CD680
CD4000-8000
1.1250/1.1245
2.1250/2.1245
2.3750/2.3745
2.8750/2.8745
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A34396
A34397
A34397
A34397
A34397
A34397
A34397