Electrical Connection; General Instructions - HBM TTS Montageanleitung

Electrical connection

6 Electrical connection
6.1

General instructions

Electric and magnetic fields often cause interference voltages in the measuring
circuit. This interference comes primarily from power lines lying parallel to the
measuring leads, but it can also come from nearby contactors or electric
motors. Interference voltage can also be coupled galvanically, especially by
grounding the measurement chain at a number of points.
Please follow the below instructions:
S Use only shielded and low‐capacitance measurement cables
circuit from HBM.
S Do not position the measurement cables parallel to power lines or control
circuits. If this is not possible (e.g. in cable shafts), protect the
measurement cable with armoured steel tubing, for example and keep it a
minimum distance of 50cm away from the other cables. Power lines or
control circuits should be twisted together (15 twists per meter).
S Guard against stray fields from transformers, motors and contactors.
S Do not ground the transducer, the amplifier and the indicator more than
once. All the measurement chain devices must be connected to the same
grounded conductor.
Grounding concept (Greenline)
The cable shield of the connection cable is connected to the measuring head of
the transducer. This encloses the measurement system in a Faraday cage.
Any electromagnetic interference active here does not affect the measurement
signal.
In the event of interference due to potential differences (equalization currents)
the zero operating voltage and the housing ground should be isolated from one
another at the amplifier and a potential equalization line should be run between
the housing and the amplifier housing (flexible stranded wire, 10 mm
conductor cross‐section).
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A01571_04_Y00_00 HBM: public
for six wire
2
TTS