Siemens SINUMERIK 840C - Manual (Page 23)

06.93 1 Prerequisites and Visual Inspection
1.2.1 Information on module handling
Additional instructions:
• Do not open the special packaging unnecessarily.
• Do not bring into contact with synthetic materials (possibility of static charging).
• Disconnect the power supply prior to insertion and removal.
1.2.2 Grounding system
Proper grounding to divert external interference is vital to trouble-free operation. It must be
ensured that the ground wires are not looped and have the required cross section.
Grounding concept
• The grounding system fulfils the requirements of the DIN VDE 0160 standard.
• The grounding concept for NC, PC, drives and machines is uniform.
• The ground connections are run in star configuration to a central mass point.
• The equipotential bonding strip is used for equipotential bonding of the external
components.
• PE terminal.
Refer to the instruction manual for an example of the grounding concept for SINUMERIK 840.
1.2.3 Position encoders
Particular attention is to be paid to the prescribed installation of the graduated scales (air gap,
etc.) and the pulse generators (coupling) (also see Heidenhain installation and adjustment
instructions).
Check to make sure that the connectors are correctly wired and properly inserted.
If the customer has inserted plug/socket connectors in the measuring-circuit cables, a careful
check must be made to ensure connection, strain relief and above all observance of the
prescribed shielding.
The use of position encoders from other manufacturers may result in inaccuracy and surface
quality problems beyond our control.
1.2.4 Cable laying
Power cables and control cables should be laid separately whenever possible. Do not produce
ground loops, as such loops or non-regulation grounding may generate ripple voltage which
would affect the speed controller setpoint. Smooth running of the motor at minimum speeds is
then no longer guaranteed.
Care must be taken that the cables are run properly and that they are rolled carefully on the
cable drum. Avoid kinking. Observe the permissible bend radii.
(Please refer to the Interface Description, Part 2, for information on connecting the cables.)
© Siemens AG 1992 All Rights Reserved 6FC5197- AA50 1–3
SINUMERIK 840C (IA)