HBK Z7A, Инструкция по монтажу

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Z7A
CONNECTION
8
5 CONNECTION
Load cells with a strain gage measuring system can be connected to:
S
carrier‐frequency measuring amplifiers, or
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DC measuring amplifiers suitable for strain gage measuring systems.
The load cells are connected using the six‐wire circuit. The wiring assignment is shown in
the following diagram.
(white)
(black)
(grey)
Excitation (+)
(green)
(red)
(Wire strand)
Excitation (-)
Sense (-)
Signal (+)
(blue)
Sense (+)
Signal (-)
Shield,
connected to housing
Electric and magnetic fields often induce interference voltages in the measurement cir­
cuit. Therefore:
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use shielded, low‐capacitance measurement cables only (HBM cables fulfill these
conditions),
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do not route the measurement cables parallel to power lines and control circuits. If
this is not possible, protect the measurement cable with steel conduit for example.
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avoid stray fields from transformers, motors and contact switches.
5.1 Parallel connection
Load cells can be wired in parallel by joining the load cell cable core ends of the same
color. In this case, HBM provides junction boxes of the
VKK... series. The output signal is
then the average of the individual output signals.
Important
Overloading of an individual load cell cannot then be detected from the output signal.