Allen-Bradley 1391B Series, Instruction Manual

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10 Chapter
10-62
Troubleshooting
Chapter Objectives Chapter 10 provides information to guide the user in troubleshooting the
1391B-ES. Included in the chapter are LED descriptions and fault
diagnosis, general system troubleshooting and test point descriptions.
System Troubleshooting Most controller faults are annunciated by the LED diagnostic indicators on
the front of the controller. Many system malfunctions manifest themselves
through a controller fault. The use of LED indications may aid in
identifying servo controller and motor malfunctions.
Table 10.A provides a listing and description of the LED indicators. In
addition, potential causes are listed.
Tables 10.B and 10.C provide a number of common system and
servomotor malfunctions and their possible causes.
Table 10.D provides a listing and description of the 1391B-ES test points.
ATTENTION: This product contains stored energy devices. To
avoid hazard of electrical shock, verify that all voltage on the
capacitors has been discharged before attempting to service,
repair or remove this unit.
Voltage at terminals 9 (+) and 7 (–) of TB5 must be “0.00” as
measured with a standard digital voltmeter or multimeter.
Only qualified personnel familiar with solid-state control
equipment and safety procedures in publication NFPA 70E
should attempt this procedure.
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