Electrical connection
TN
A01639_02_X00_00
HBM: public
19
7.1
General instructions
We recommend to use shielded, low-capacitance cable from HBM for the
electrical connection between torque transducer and measuring amplifier.
With cable extensions it is important to ensure that a good connection is
provided, with minimum contact resistance and good insulation. All plug
connections or cap nuts have to be tightened firmly.
Do not route measurement cables in parallel to power lines and control circuits.
If this is not possible (for example in cable ducts), maintain a minimum
distance of 50 cm and protect the cable with a steel tube.
Avoid transformers, motors, contactors, thyristor controllers and similar
sources of stray fields.
7.2
Cabling 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.
S
Use only shielded and low‐capacitance measurement cables for six wire
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 measure
ment cable with armoured steel tubing, for example and keep it a minimum
distance of 50 cm away from the other cables. Power lines or control cir
cuits 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.