CEMB TR-NC/8, Инструкция по эксплуатации и обслуживанию

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Vibration equipment division
15
TR-NC/8 - R
ev
.02/2013
5.2.3 c
ablE shiElding
Always use shielded cables and connect the shield only on one side of the wiring.
It is recommended to use the device side in order to guarantee equipotentiality between the cable shielding and the earth
reference.The shield must cover the cable up to the device input, possibly avoiding braid interruptions, which reduce the
leakage capacity..
5.2.4 E
arthing
A system should have dedicated earth cables for the power and the control and they should come together only upstream
of the earth stake. Otherwise, slight leakage to earth of a power device might shift the zero reference of the control device.
The earth cable must have an as large as possible cross-section (minimum 4 mm²) in order to ensure low impedance.
All the device earth references (boards, acquisition system, cable shields) must refer to a single earth point.
5.2.5 T
roublEshooting
The persons that work with the TR-NC8 monitoring system must have adequate technical training and qualifications.
Recommended operations to check for system faults:
TYPE OF FAULT 4-20mA LOOP READING
Demodulator not connected or damaged 0mA
Sensor not connected or damaged about 2mA