week 1 Flashcards
the ability of a device or mechanism to do a
specific amount of work over a period of time.
Power –
a unit of power commonly use in the farm to
indicate the work output of humans, draft animals, and
mechanical prime movers
Horsepower –
– the rate at which a machine or an
implement can cover a field while performing its
intended function.
field capacity
is driven by solar
radiation and the rotation of the earth
- Global wind circulation
in the northern hemisphere
Northeast trade winds
in the southern hemisphere
Southeast trade winds
is a machine that convert the
kinetic energy of the wind to mechanical
power for pumping water.
Windpump
it does not cause pollution. No burning of fuel
is required
clean
supply of wind is adequate throughout
the year.
Abundant
No cost on fuel and minimum labor for
operation is required. Technology can be localized to
reduce investment cost.
Cheap –
Wind is continuously available and will
never run
out.
Sustainable –
it is equipped with safety devices that protect
the machine from strong wind.
safe
– It creates employment and development
of local industry.
Economic
– It can be used for mechanical
as well as for power generation to reduce cost of
production in agriculture and other industries
Varied Applications
applicable or adoptable only in areas
with wind speed of 3 mps or higher.
Site specific
– it requires water reservoir or batteries
due to considerable power supply variation.
Need Storage
Requires back-up system for area
where wind supply is low
Back-Up System
High initial cost which makes it not
attractive investment in competition with other
alternative energy sources.
High Initial Cost
– motor is operated for more
than 60 minutes without rest.
CONTINUOUS duty rating
is operated only for a few
minutes at a time with a rest or cooling period between
operations
INTERMITTENT duty rating –
Case or housing which prevents the operator from
accidental contact with energized parts and protect the
motor from physical damage.
ENCLOSURE
allows easy movement of air through
the inside of the motor by providing slots or holes in
the end shields or frame where the air can pass
through
OPEN TYPE
Does not allow entry of air inside the motor.
* Fan blows air on the outside surface of the frame
to dissipate heat.
* Fins are constructed on the frame to increase the
surface area for heat dissipation.
TOTALLY ENCLOSED TYPE
Indicates the maximum load that can be
successfully carried by the motor if it is to operate
continuously and remain within a safe temperature
range
SERVICE FACTOR
