18
6
Connections
6.1 Instructions for cabling
Electrical and magnetic fields often cause the induction of noise/interference
voltage in the measuring circuit. This interference is primarily caused by
high−power transmission lines parallel to the measuring leads, but also by
contactors and electric motors in the vicinity.
Please note the following instructions:
• Always use shielded, low−capacity measurement cable (HBM cables meet
these requirements).
• Do not lay measurement cable parallel to high−voltage power lines or
control circuits. If this is not possible (e.g. in cable ducts) protect the
measurement cable, e.g. with armoured steel tube and maintain a minimum
distance of 50 cm from the other cables. High−voltage power lines and
control lines should be twisted (15 turns per metre).
• Avoid stray fields of transformers, motors and contactors.
• Do not earth transducer, amplifier and display device more than once. All
the devices in the measuring chain are to be connected to the same
earthed conductor.
• The screen of the connection cable is connected to the transducer housing.
HBM
C6A
A0638−2.3 en/de/fr