Rockwell Automation 1746-HSTP1 Stepper Controller Module/ User Manual - Manual (Page 29)

Publication 999-121 - December 1999
3-2 Start Up and Troubleshooting
More detailed troubleshooting information is provided in the
following list:
Problem Resolution
No green RUN LED Either a major Module malfunction or lack of power from
the backplane is indicated. Check for power from the
backplane first; if power is present, the Module must be
replaced.
Red FLT LED is lit Module is improperly configured. Refer to the topic,
“Configuration Mode” in Chapter 4 of this manual for
additional information.
Red ERR LED is lit This means that invalid data has been copied into one of
the command mode output words (position, velocity,
acceleration and/or deceleration). The invalid data must
first be corrected in the appropriate “N” file of the SLC
Processor, and the error then reset. The error is reset by
resetting bit 15 of the configuration mode output word 0
to a logic “10”.
Module completes one
move, and stops The Module is not “seeing” the 0 to 1 transition required
for each new move (either absolute or relative). To avoid
this condition, it is recommended, when programming,
that you unlatch bits 0 and/or 1 each time a move is in
progress. Note that this will not cause a problem when
toggling between absolute and relative moves.
Module Ready bit goes
false during operation This could be the result of a poorly seated Module.
Check that the Module is properly inserted in its slot. If
the Module appears to be properly seated, request help
from Allen-Bradley Technical Support. Be sure to provide
a copy of the program involved, and as many other
details as you can about the circumstances that trigger
the fault to assist in the solution of the problem.
Limit switch inputs Limit switch inputs are detected by and their states are
reported by the Module software. If they are not reading
properly:
1) check input signal levels
2) check state setting in configuration
3) check wiring.
Limit switch data can be read by accessing configuration
mode input word 1. Incorrect limit switch states can be
altered by setting the respective bits in configuration mode
output word 1 (refer to the “Configuration Mode” topic in
Chapter 4 of this manual).
Encoder is not reading
This condition can be due to any of the following errors:
improper voltage level is being provided to the encoder by the
encoder power supply; improper signal level from the
encoder, encoder miswired; or, the Module has not been
configured to accept encoder input (IMPORTANT:
The Module
operates differently when loop back diagnostics are active;
this mode uses a pulse train and direction bit versus
quadrature encoder pulses). Correct the encoder power
supply voltage level or reconfigure the Module as applicable.