General Description; System Composition - CEMB TR-NC/8 Manual Del Usuario

1.

General description

Monitoring vibrations of machinery in operating conditions allows examining the trend of the vibrations over time,
predicting which part will start to deteriorate first and planning maintenance so as prevent production stops be-
cause of serious faults and the consequent economic losses.
Rarely does a vibratory phenomenon develop over time according to linear or known laws; sometimes it increases
gradually, as in the case of wear, other times rapidly, as in the case of faulty lubrication, or it occurs suddenly and
severely, as in the case of breakage of turbine blades.
You can act timely to prevent major damage caused by high vibrations only by continuous monitoring using instru-
ments equipped with alarm and locking devices that are activated when vibration exceeds preset safety limit values.
Vibration is monitored by means of a sensor facing the rotor in correspondence to the measuring point and a cable
connected to a signal power and processing board.
Initially designed and developed for monitoring steam turbines of large thermoelectric power stations (where they
are of vital importance), continuous monitoring instruments (whose cost has come down considerably) have proved
to have manifold application possibilities and usefulness in the most varied industrial plants, wherever there are
high-end machines that need to be highly accurate and maintained such over time, or auxiliary machines (fans,
pumps) whose failure would cause production stops with the resulting economic losses.
The transmitter operates with a current loop of 4-20 mA and, depending on the model, has a current output propor-
tional to the distance between the sensor and the target (displacement measurement), the target vibration (vibra-
tion measurement) or the gearwheel rotation speed (speed measurement).
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System composition

The TR-NC8 measuring system is made up of three parts:
• ST-NC/8 series no-contact sensor
• T-NC/API series extension cable
• TR-NC8 - TR-NC8 V transmitter
No-contact sensor Extension cable
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