Preventative Maintenance Plan
The key to the successful operation of any utility or
industrial location, is Preventative Maintenance. Being able to identify
potential problems in your equipment is the first major step in insuring that
your production processes are not interrupted due to equipment failure. Of the
different areas of concern, the electrical system is of utmost priority. The
ability of your electrical distribution system to deliver the required amount of
power to each individual process is probably the most important asset of your
facility.
The electrical
distribution system of any facility is comprised of many different pieces of
equipment. In a typical large-scale production facility, power is usually
supplied by the local utility at a very high voltage. This very high voltage (
usually ranging from 69 KV to up to 230 KV ) is then stepped down to the desired
distribution voltage of 5 KV to 15 KV for distribution throughout the facility.
At numerous areas or load centers, the voltage is further stepped down to a
usable voltage, which is usually 208 volts or 480 volts. At each of these step
down points, transformers are used to change the voltages. If any of these
transformers fail to perform their duty, the entire system is severely crippled
or worse, completely useless.
“What
can be done?”
To
insure the smooth operation of the electrical distribution system, the owner
must know the condition of each piece of the installed equipment. Periodic
inspections of the equipment are a must. In addition, periodic testing of each
piece is advised.
Transformers,
being the most important piece of the equipment, should be thoroughly inspected
at least once a year. The external surfaces should be inspected for signs of
rusting and/or excessive corrosion caused by exposure to adverse conditions. The
gaskets of each unit should be inspected for signs of cracking and other damage.
The bushings should be inspected for evidence of leaking dielectric fluid and if
found, corrected immediately. Gauges and monitoring equipment should be
inspected for proper indication and operation. The technician should make note
of the operating temperature of the unit and on units equipped with a high
temperature indicator, a record of the highest temperature at which the unit
achieved should be made. The oil level of the unit should be noted to insure
that no fluid has been allowed to escape unnoticed.
Each
of these external inspections can be performed at any time whether the unit is
in service or not. This is not the case, however, for an internal inspection.
For an internal inspection, the unit must be de-energized and removed from
service. Due to the fact that in some cases, shutting down one transformer could
completely shut down a plant, internal inspections of transformers are not
always performed on a routine basis.
“Ok, what can I do? I do want to know the condition of my transformers, but, I do not want to stop all production in my facility.”
Although
an internal inspection on an energized transformer is not possible, there are
tests that you can perform to determine the electrical condition of a
transformer. The most common test is to draw oil samples from the unit and test
them for Dissolved Gasses (DGA) and General
Screening Test of the oil condition.
The
Field Service department at Alamo Transformer is staffed by knowledgeable
technicians who stand ready to aid you in developing and maintaining a
comprehensive Preventative Maintenance Program designed around your particular
business and schedule. In addition,
the field service personnel are able to remedy most minor problems on-site thus
negating the need for removal of the transformer from service.
As
part of each PM plan, the technician will perform a visual inspection of all
external surfaces of the unit. He will draw the oil samples and ready them for
testing in the laboratory. Chain-of-Custody procedures dictate that each
sample be carefully identified with the appropriate nameplate data
including the Serial Number. After testing has been performed, a copy of all
results are forwarded to the customer along with any recommendations for
remediation of any problems noted. Copies of all test results will be maintained
in our office in a secure database, for use in comparison to all subsequent
testing that is performed on a particular unit.