This document discusses factors that can influence the performance of equipment and provides suggestions for proper preventative maintenance. It covers environmental factors like temperature, moisture, dust and power supply issues. Recommendations are given for cleaning, lubrication, ventilation and using surge protectors to prevent equipment failures and extend equipment life.

1. By Daniel N.D. Afuwai
E.M.D.C., A.B.U. ZARIA November 2011

2.  Environment is defined as conditions
influencing development or growth.
Engineers, Technologist and Scientists are
responsible for the environment that
equipment are kept; where students and staff
work , which should be conducive.
 Adequate care of equipment makes sense
these days of dwindling funds in the
Departments and personally. Due to lack of
trained personnel we may find repairs very
expensive.

4.  If you misuse your equipment by not
following the instruction in the manual
provided by the manufacturer or do not
protect it from environmental elements, you
can be the cause of its failure. A few
moments of care can yield many more hours
of good performance.
 Proper preventive maintenance begins with
an understanding of what we are fighting.

5.  The following factors can influence the
performance of your equipment:
◦ Extremes of temperature
◦ Moisture & corrosion
◦ Dust and foreign particles
◦ Power line problems
◦ Human factors
Each of these can lead to equipment breakdown

6.  The Ics, belts, insulators and other devices in
the equipment are very sensitive to high
temperatures. As long as boards and chassis
are not too hot to touch, the amount of heat
being produced should not cause any
damage.

7.  The following suggestions should help to
prevent heat related failures:
Keep the dust cover off during operations
Allow plenty of ventilation around the unit
Keep cooling vents clear and unblocked
Keep system dust free inside and outside
by using compressed air to rid the system
of dust.

8.  Towards the end of the dry season, rapid
changes of temperature leads to build up of
humidity and condensation on the metal
chassis and circuit boards, which leads to
tarnishing, short circuit and possibly damage
to the equipment.
 Equipment should be covered with cotton
cloth after use and not with plastic cover.
 Silical gel is useful in preventing build up of
moisture in equipment

9.  The metal connector pins on cables, circuit
boards, IC pins, and other component leads are
subject to corrosion. Corrosion can damage not
only electronic connections in equipment but
connections in mechanical section as well.
 Corrosion is caused by chemical attack from
spilled reagents, corrosive atmospheres, and
even touching delicate metal contacts with our
fingers! Don’t touch circuit board contacts with
your fingers because the oil in your fingers
contain salt to begin oxidation of the pins.

10.  The best preventive action is cleaning and
lubrication to keep the electrical contacts,
gears & bearings from oxidation buildup and
prevent corrosion.
 Oxidation of some contacts can be cleaned by
using soft rubber eraser, or contact cleaner
spray. Do not use sand paper as it will grind
the metal plating. Spraying the pins with
contact cleaner spray is an effective corrosion
preventive.

11.  During the HARMATAN, dust is the main
problem in Nigeria because dust enters
through the smallest slots & cause problems
such as:
 Dusty work place and living area
 Clogging of ventilation systems &
moving parts
 Bad electrical Contacts
 Wear on all moving mechanical parts

12.  The build up of dirt and dust on circuit
boards creates an insulation blanket that
prevents the release of heat generated
during normal operation, which leads to
overheating then failure of the mechanical
or electronic components of the equipment.
 Dust settles on lenses and reflective
surfaces leading to degradation in
performance of optical systems.

13.  Tobacco smoke increases the failure rate of
rubber tires & belts in the mechanical section
of equipment.
 Foreign particles such as food crumbs, are a
great attraction for insects & rats!, which have
been known to wreck havoc on rubber tubing
and electrical cables.
 Therefore do not smoke instrument rooms or
laboratories. Clean and clear up any food
spills and crumbs.

14.  If we clean our work area daily, if we cover our
equipment after use with dust covers, the
problem of dust is minimised and dust cannot
accumulate. We have to do it ourselves, we
cannot wait for someone else to do it for us.
 The use of oil free compressed air to blow out
dust and dirt from inside the equipment at
regular intervals is highly recommended.
 It is important to wash labs floors rather than
sweep with brooms, because brooms raise dust
into the equipment.

15.  Good clean power supply is essential for the
proper functioning of scientific equipment.
Unfortunately, provision of this service is an
exception rather than a rule. In fact over 50% of
equipment breakdown can be traced to problems
caused by power fluctuations and erratic supply.
There are four types of power line problems that
cause concern:
Brown outs & line dips
Blackouts
Mains borne Transients
Noise

16.  Brownouts – are those planned and sometimes
unplanned reduction of voltage resulting from
an unusually high demand in electric power. This
5% to 15% drop in voltage can last for several
hours. During brownouts, equipment tend to
operate intermittently, motors/fans tends to
overheat & some equipment simply shut down
while others lock up. Do not operate equipment
during a brownout as it places a severe stress on
the equipment and accelerates the condition of
which equipment power supply fails.

17.  A voltage dip –is a short reduction in line voltage
due to a mains fault or sudden increase in
electrical load. This happens when equipment are
operated in the same line with arc welders,
grinding machines or air conditioners. This is
very harmful to sensitive equipment as
computers.
 A blackout is a total loss of line voltage. When
power goes out be careful and be sure that when
power is restored – a tremendous voltage spike
will be produced as lights & motors go On all
over the neibourhood, which could damage your
equipment.

18.  Always unplug your equipment when a blackout
occurs, and wait till power is restored for some
few minutes before plugging in the instruments.
The automatic voltage switch (AVS) and
Uninterruptable Power Supply (UPS) are
indispensable.
 Line Transients are a momentary overvoltage/
under voltage conditions often cause by
lightning, start up of nearby large electrical
equipment such as motors or arc welders.
Transients disrupts system operation of
microprocessors or damage sensitive equipment.

19.  Electrical Noise consists of high frequency
and high voltage interference on the power
line and often affects equipment such as pH
metres, computers, radios, tvs etc. Its main
symptoms are visible white streaks in the
lower portion of the computer screen, and in
pH metres unstable readings. These problems
are solved using filters, grounding the
installation and shielding the signal leads of
the instrument properly.

20.  1. Use uninterruptible power supply(UPS) of
adequate power rating for the equipment in
question.
 2. Use of ferro-resonant transformer type
Line Conditioner.
 3. Use of voltage stabilisers that use
electronic components and relays; these are
useful in the absence of line conditioners as
they are affordable.

21.  ELECTRICAL PRECAUTION
◦ a, All single phase mains sockets and plugs should be
three pin.
◦ b, Connections between equipment and plugs should be
made with three core flexable cable of suitable current
rating.
◦ C, Use the correct fuse for the equipment chosen as
provided or calculate the current drawn by the
equipment and use it to select the fuse. The formula is
Current(I) = Power(P) divide by Voltage (V). (Give
example on board). NEVER use a nail or a very thick
length of wire to replace a fuse , even as a temporary
measure.
◦ D. Plugs and other fittings should be wired correctly.
This to be done practically

22.  Sockets should not be overloaded. If using a
number of plugs (equipment) the proper multi-
way adaptors should be used and the total rating
of the equipment attached should not exceed the
maximum rating of the socket.
 Equipment should be isolated from the mains
whilst maintenance takes place.
 All plugs, sockets and wiring should be inspected
and tested by competent person at least twice a
year, for earthing, insulation, isolation and
suitable fuses.

23.  TO CONCLUDE
 Ensure that no one, as a result of using
electrical equipment, is ever put in a situation
where an electric current might pass through
his body.
 Ensure that unnecessary electrical heating
never occurs in wires, cables, flexes, plugs,
sockets or connectors.
 THANKS