Cable Extension And Cable Shortening; Emc Protection - HBM C9C Mounting Instructions

7.1.2

Cable extension and cable shortening

Various connection cable lengths are available for the C9C so that extension
cables or cable shortening are generally not necessary.
As the transducer has a 4-wire configuration, the cable is also used to
compensate the temperature dependence of the sensitivity. We therefore do
not recommend shortening the cable and extension cables should be
implemented in a 6-wire configuration. Please note the operating instructions
for your amplifier system in this case. All C9Cs ordered with fitted connectors
come with 6-wire configuration as of the connector. See the Specifications
section 9 on page 29 of this manual for the connector pin assignment. Please
remember that an extension cable must have six wires. Such an extension will
have no influence on the measurement. If you have selected the "Sub HD" (for
QuantumX) option as the connector in combination with the "TEDS" option,
you must extend with seven wires as in this case, a so-called "one-wire TEDS"
is fitted and this requires two additional wires.
With extension cables, ensure that the connection is perfect with a low contact
resistance and continue to connect the cable shield extensively. Note that the
protection class of your force transducer will decrease if the cable connection
is not tight and water can penetrate the cable. Transducers can be irreparably
damaged and fail in these circumstances.
7.1.3

EMC protection

Electrical and magnetic fields can often induce interference voltages in the
measuring circuit. Pay attention to the following points to avoid this:
S Use shielded, low-capacitance measurement cables only (HBM cables fulfill
both conditions).
S Do not route the measurement cable parallel to power lines and control
circuits. If this is not possible, protect the measurement cable with metal
tubing.
S Avoid stray fields from transformers, motors and contact switches.
S Note that compensating currents flowing through the cable shield can cause
major interference. If the sensor and your evaluation unit are at different
electrical potentials, an electrical connection with very low resistance must
be provided.
C9C
A03729_03_YI0_01 HBM: public
Electrical connection
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