Manual

Chapter
10
101
Troubleshooting
This chapter describes the LED indicators on the 1771-M3 controller and
1771-ES expander modules. It also presents a troubleshooting flowchart.
The flowchart provides a logical sequence for evaluating servo
positioning assembly condition. Used in conjunction with the indicators
and the status block, it can help you detect problems in servo positioning
assembly operation.
The status block provides continually updated information about axis and
servo positioning assembly conditions. Refer to chapter 7, section titled
“Status Block” (p. 7-4) for a detailed description of the status block.
The servo controller module has three indicators (Figure 10.1):
Figure 10.1
1771M3
Controller Indicators
SERVO
CONTROLLER
Processor Communication
Fault (Red)
Expander Communication
Fault (Red)
Active (Green)
Processor communication fault (PROC COMM FAULT) - This red
indicator is normally off. It turns on to indicate a communication fault
between the PC processor and the 1771-M3 controller. Such a font
could be caused by hardware, or by a data block overlapping a
Chapter Objectives
Monitoring 1771M3 Controller
Indicators