Electrical Connection; General Hints; Shielding Design - HBM t40 Montageanleitung

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Electrical connection

4.1 General hints

To make the electrical connection between the torque transducer and the
amplifier, we recommend using shielded, low capacitance measurement
cables from HBM.
With cable extensions, make sure that there is a proper connection with
minimum contact resistance and good insulation. All plug connections or
swivel nuts nuts must be fully tightened.
Do not route the measurement cables parallel to power lines and control
circuits. If this cannot be avoided (in cable pits, for example), maintain a
minimum distance of 50 cm and also draw the measurement cable into a
steel tube.
Avoid transformers, motors, contactors, thyristor controls and similar
stray field sources.
CAUTION
Transducer connection cables from HBM with plugs attached are
identified in accordance with their intended purpose (Md or n). When
cables are shortened, inserted into cable ducts or installed in control
cabinets, this identification can get lost or become concealed. If this is
the case, it is essential for the cables to be re labeled!

4.2 Shielding design

The cable shield is connected in accordance with the Greenline concept. This
encloses the measurement system (without a rotor) in a Faraday cage. It is
important that the shield is laid flat on the housing ground at both ends of the
cable. Any electromagnetic interference active here does not affect the
measurement signal. Special electronic coding methods are used to protect
the purely digital signal transmission between the transmitter head and the
rotor from electromagnetic interference.
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, 10mm
crosssection).
If potential differences arise between the rotor and the stator on the machine,
perhaps due to unchecked leakage, and this causes interference, it can
HBM
T40
2
wire
A2463 5.0 en/de