TABLE OF CONTENTS Many faults occur because machines are incorrectly specified for the application to which they are being applied. For example, a machine may be underpowered or have an inadequate enclosure. The specification of a machine must ensure that it is of an appropriate design for the use to which it is being put. It is a waste of time applying sophisticated monitoring techniques to a machine that is unfit for its purpose. It is far better to remove the monitoring and change the machine for one that is more suited to the application. By the same token many operational problems could be avoided by using an over-designed machine. For example, in a hot environment it may be better to use an over-rated machine, which has a substantial design margin, than push an adequately designed machine to its limit. On the other hand, it is sometimes an operational fact of life, especially with an expensive machine, that it must continue to operate even though it suffers from shortcomings in the original specification. In such cases effective monitoring can help to ease the burden placed upon the maintenance engineer.
The specification of a machine must reflect the mechanical, electrical and environmental conditions in which the machine will work. These matters will have a bearing on the mechanisms by which the machine may fail in service. The need for monitoring and the selection of the parameters to be monitored must be affected by these operational conditions. Table 2.6...
