SKF CMPT CTU, Инструкция по эксплуатации

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CMPT CTU Output
SKF Copperhead Transmitter Unit CMPT CTU 8-22
Instruction Manual
CMPT CTU Output
8
Each machine has its own normal vibration level depending on its function and design,
supporting structure, and environment. The CMPT CTU is particularly useful for
continuous detection of changes in machinery vibration and temperature. The CTU
analog output signals can be monitored either by the PLC/DCS system or the CMPT
DCL modules. For new machinery or for machinery known not to have any preexisting
faults, the alarm levels in PLC/DCS or DCL modules can be set at 50 % to 100 % (1,5 to
2 X) over the normal machine vibration level. Lower vibration alarm levels should be
used if the condition of the machinery is not known. Table 8-6 and Table 8-7 below can
be used to judge the severity of vibration in a machine. Generally, Acceleration
Enveloping vibration (gE3) values above 12 to 15 gE3 are indications of faults such as
mechanical looseness, lack of lubrication, and bearing defects. Consult SKF for
additional details about vibration levels.
Alarm limits for temperature monitoring can be established based on experience of the
original equipment manufacturer (OEM) or the machinery operator.
When high vibration or temperature levels are detected, it is advisable for the plant
operator or maintenance personnel to inspect the machine. Very often, these personnel
can detect faults based on unusual sounds or noise. Procedures are available to help
diagnose faults in machinery. If the cause of the fault cannot be identified, it is advisable
to use the experience of a vibration analyst to perform a complete vibration spectrum
analysis of the machine.
Class I (Small machines)
Machines may be separated driver and driven, or coupled units comprising operating
machinery up to approximately 15 kW (approx. 20 hp).
Class II (Medium machines)
Machinery (electrical motors 15 kW (20 hp) to 75 kW (100 hp), without special
foundations, or rigidly mounted engines or machines up to 300 kW (400 hp) mounted
on special foundations
Class III (Large machines)
Machines are large prime movers and other large machinery with large rotating
assemblies mounted on rigid and heavy foundations which are reasonably stiff in the
direction of vibration.
Class IV (Large machines)
Includes large prime movers and other large machinery with large rotating assemblies
mounted on foundations which are relatively soft in the direction of the measured
vibration such as turbine generators and gas turbines greater than 10 MW
(approximately 13 500 hp) output.
Table 8-5:
ISO 10816-1 Machine classifications