Parallel Connection; Transducer Connected In The Four-Wire Technique; Cable Extension - HBM Z7A Série Notice De Montage

Z7A/...
Electric and magnetic fields often induce interference voltages in the mea-
surement circuit. Therefore:
• use shielded, low-capacitance measurement cables only (HBM cables fulfill
these conditions),
• do not route the measurement cables parallel to power lines and control cir-
cuits. If this is not possible, protect the measurement cable with steel con-
duit for example.
• avoid stray fields from transformers, motors and contact switches.

3.1 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... se-
ries. The output signal is then the average of the individual output signals.
CAUTION
Overloading of an individual load cell cannot then be detected from the
output signal.

3.2 Transducer connected in the four-wire technique

Upon connection to amplifiers using the four-wire circuit, the cores bl (blue)
and gn (green) should be connected, as should bk (black) and gr (gray). The
following deviations occur in the case of cable of original length (6 m): Sensi-
tivity −0.4 % and temperature coefficient −0.02 %/10 K.

3.3 Cable extension

Extension cables must be shielded and of low capacitance. We recommend
the use of HBM cables, which satisfy these requirements.
HBM extension cables, 6 wires:
− KAB8/00-2/2/2 (sold by the meter, order-no. 4-3301.0071 = grey or
4-3301.0082 = blue)
− CABA1 (cable roll, order-no. CABA1/20 = 20 m or CABA1/100 = 100 m in
length)
A1847-1.1 de/en/fr
21
HBM