Possible Causes Of Errors - HEIDENHAIN iTNC 530 Service Manual

11.2 Possible Causes of Errors

General
information
Additionally for the
use of PROFIBUS
11 – 118
PLC power supply missing
Overload, short-circuit on an output
Defective PLC input at the MC or the PLC expansion card
Defective PLC output at the MC or the PLC expansion card
Defective cable or connector
Faulty clamp or screw connection
Bouncing switches (e.g. mechanical pushbutton switches)
Poor shielding and grounding
Electromagnetic fields
Disturbance in the PLC bus
Compensating currents caused by different potentials
Example:
Several electrical cabinets are connected with a bus.
Due to poor grounding, these cabinets do not have the same potential.
The shielding of the bus is connected to each electrical cabinet.
Result: Compensating currents
Fault in the PROFIBUS
Fault in a bus (e.g. ASI bus) connected to the PROFIBUS
Terminating resistors missing at the ends
HEIDENHAIN Service Manual iTNC 530