User's Manual

24
The cable shield is connected with the transducer housing. This encloses the measurement
system (without the rotor) in a Faraday cage when the shield is laid flat at both ends of the
cable. With other connection techniques, an EMC-proof shield should be applied in the wire
area and this shielding should also be connected extensively (see also HBM Greenline
Information, brochure i1577).
Electrical and magnetic fields often induce
interference voltages in the measuring circuit.
Therefore:
• Use shielded, low-capacitance measurement cables only (HBM cables fulfill both
conditions).
• Only use plugs that meet EMC guidelines.
• Do not route the measurement cables parallel to power lines and control circuits.
If this is not possible, protect the measurement cable with e.g. steel conduit.
•
Avoid stray fields from transformers, motors and contact switches.
•
Do not ground the transducer, amplifier and indicator more than once.
•
Connect all devices in the measurement chain to the same grounded conductor.
• In the case of interference due to potential differences (compensating currents),
supply voltage zero and housing ground must be disconnected on the amplifier and a
potential equalization line established between the stator housing and the amplifier
housing (copper conductor, minimum 10 mm
2
wire cross-section).
• Should differences in potential between the machine rotor and stator, because of
unchecked leakage, for example, cause interference, this can usually be overcome
by connecting the rotor definitively to ground, e.g. with a wire loop. The stator must
be connected to the same (ground) potential.
Version b 13.01.2015 HBM: public