Installation manual

Appendix B 08/04 Danaher Motion Kollmorgen
106 M-SS-001-01 Rev. T SERVOSTAR S Installation
B.1.7 TROUBLESHOOTING
Several problems can occur with encoder-based systems.
The most common problem is miswiring. The section on
system phasing provides the necessary troubleshooting
information.
Miswired Hall channels can cause intermittent problems.
With miswired Hall channels, the motor operates correctly
sometimes, but will occasionally not operate correctly after
cycling power. It is very important to physically verify the Hall
effect channels. There is a command in the SERVOSTAR
manual called, HALLS. It returns the hall code as read. It is
important that the installation and startup procedures for the
machine sequence the motors through all the appropriate
hall codes to make sure they are present and in the right
sequence.
An 'illegal hall code' error occurs if the Hall channels go to all
low or all high conditions. A broken wire or misphased
channel can cause this problem.
It is important that the A and the B channels be wired
appropriately to the SERVOSTAR drive to ascertain the
correct directional drive information. This can be verified by
displaying the PFB variable while rotating the motor shaft
clockwise. The PFB variable should be counting in a more
positive direction. If it counts in a negative direction, the A
and B channels are inverted. This can be fixed by swapping
the A and /A wires from the encoder or by using the MFDIR
command.
A/B Line Break errors may occur and can be misleading.
The SERVOSTAR receives the A/B/I channels in a
differential format. Each channel is fed into a bridge rectifier
to create a DC voltage that is monitored for presence.
Absence of any one of these three voltages (except the I
channel in MENCTYPE3, MENCTYPE4, and MENCTYPE6)
cause an A/B line break fault.
B.1.7.1 Line Drivers, Receivers, and
Terminations
Counting pulses sent over cables going through an industrial
environment requires that care be taken to prevent noise induction
on the cable that looks like an encoder pulse. Running wires in a
clean raceway is one requirement.