Page 350 - Intro Predictive Maintenance

Establishing a Predictive Maintenance Program 341

hardware configuration, computer operating system, hard disk memory requirements,
and many others. This can become a serious if not catastrophic problem. You may find
that one system requires a special printer that is not compatible with other programs
to provide hard copies of reports or graphic data. One program may be compatible
with PC-DOS, whereas another requires a totally different operating program.

Therefore, you should develop a complete computer specification sheet for each of
the predictive maintenance systems that will be used. A comparison of the list will
provide a compatible computer configuration to support each of the techniques. If this
is not possible, you may have to reconsider your choice of techniques. Computers,
like plant equipment, sometimes fail. Therefore, the use of a commercially available
computer is recommended. The critical considerations include availability of repair
parts and local vendor support.

Most of the individual predictive maintenance techniques do not require a dedicated
computer. Therefore, there is usually sufficient storage and computing capacity to
handle several, if not all, of the required techniques and still leave room for other
support programs (e.g., word processing, database management). Use of commercially
available PCs provides the user with the option of including these auxiliary programs
in the host computer. The actual configuration of the host computer will depend on
the specific requirements of the predictive maintenance techniques that will be used.
Therefore, we will not attempt to establish guidelines for selection.

The Software
The software program provided with each predictive maintenance system is the heart
of a successful program. It is also the most difficult aspect to evaluate before pur-
chase. The methodology used by vendors of predictive maintenance systems varies
greatly. Many appear to have all of the capabilities required to meet the demands of
a total-plant predictive maintenance program; however, on close inspection, usually
after purchase, they are found to be lacking.

Software is also the biggest potential limiting factor of a program. Even though all
vendors use some form of formal computer language (e.g., Fortran, Cobol, Basic),
their programs are normally not interchangeable with other programs. The apparently
simple task of having one computer program communicate with another can often be
impossible. This lack of compatibility among various computer programs prohibits
transferring a predictive maintenance database from one vendor’s system into a system
manufactured by another vendor. The result is that once a predictive maintenance
program is started, a plant cannot change to another system without losing the data
already developed in the initial program.

At a minimum, the software program should provide automatic database manage-
ment, automatic trending, automatic report generation, and simplified diagnostics.
As in the case of the microprocessor used to acquire data, the software must be
user-friendly.