SKF CMPT CTU, Инструкция по эксплуатации

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Basic Instructions and Wiring Connections
Normal Wiring as Vibration and Temperature (optional) Transmitter
SKF Copperhead Transmitter Unit CMPT CTU 7-18
Instruction Manual
Normal Wiring as Vibration and Temperature (optional) Transmitter
This applies to SKF CMPT sensors 2310, 2310T, 2323 and 2323T.
The sensor ground wire is connected to the inner shield of the sensor cable. This wire should be connected to
ground (earth) inside the CMPT CTU enclosure. The sensors have a stainless steel over braid. The braid is
for mechanical protection of the cable. The braid also acts as an outer shield. It is advised to isolate (shield)
the sensor ground wire from the braid and local ground. The cable braid and the sensor ground wire should
not contact each other or else a “ground loop” may occur causing signal interference.
Figure 7-4:
Basic CMPT CTU with wiring
The CMPT accelerometer sensor is connected to the CMPT CTU according to the wiring
diagram in Figure 7-4.
The CTU can directly interface with a plant automation system via a Programmable
Logic Controller (PLC) / Distributed Control System (DCS) using both the processed
vibration and temperature analog output signals. The accelerometer and CTU can be
located up to 1,6 km (1 mile) away from the PLC/DCS when using the 4
-
20 mA current
signal outputs and recommended wire size (2,5 mm (22 AWG) at 100 pF/m).
The processed vibration signals of the CTU can be “averaged” to dampen the change in
processed vibration output signal. This feature is useful if the vibration level in the
machine is dynamic making the setting of alarm(s) in the PLC/DCS difficult or the
observation of the PLC / DCL digital display uncomfortable for the operator. Use RANGE
settings 4 to 7 or C to F to enable the “Output averaging ON” configuration.
The SENSOR OK lamp will be red if the temperature sensor is not connected. A 100
W
or a 120
W
resistor is required between CTU terminals 2 and 3 to avoid the red
SENSOR OK lamp.