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GENERATOR INFORMATION
USE OF ELECTRIC MOTORS
The power required to start an electric motor is considerably
more than is required to keep it running after it is started.
Some motors require much more current to start them than
others. Split-phase (AC) motors require more current to start,
under similar circumstances, than other types. They are com-
monly used on easy-starting loads, such as washing
machines, or where loads are applied after the motor is
started, such as small power tools. Because they require 5 to
7 times as much current to start as to run, their use should be
avoided, whenever possible, if the electric motor is to be dri-
ven by a small generator. Capacitor and repulsion-induction
motors require from 2 to 4 times as much current to start as
to run. The current required to start any motor varies with the
load connected to it.
An
electric motor connected to an air
compressor, for example, will require more current than a
motor to which no load is connected.
In
general, the current required to start 115- Volt motors connected
to medium starting loads will be approximately as follows:
MOTOR SIZE
AMPS FOR
AMPS FOR
(HP)
RUNNING
(~TARTING
(AMPERES)
AMPERES)
1/6
3.2
6.4
to
22.4*
1/4
4.6
9.2
to
32.2*
1/3
5.2
1 0.4
to
72.8 •
1/2
7.2
14.4
to
29.2*
3/4
10.2
20.4
to
40.8*
1
13
26
to
52
*NOTE: In the above table the maximum
Amps for Starting is
more for some small motors than for larger ones. The reason
for this is that the hardest starting types (split-phase) are not
made in larger sizes.
Because the heavy surge of current needed for starting
motors is required for only an instant, the generator will not
be damaged if it can bring the motor up to speed in a few
seconds. If difficulty is experienced in starting motors, tum
off all other electrical loads and, if possible, reduce the load
on the electric motor.
REQUIRED OPERATING SPEED
Run the generator first with no load applied, then at half the
generators capacity, and finally loaded to its full capacity as
indicted on the generators data plate. The output voltage
should be checked periodically to ensure proper operation of
the generating plant and the appliances it supplies. If an AC
voltmeter or ampmeter is not installed to monitor voltage and
load, check it with a portable meter and amp probe.
NOTE: When the vessel in which the generator is installed
contains AC equipment of 120 volts only, it is recommended
that the generators AC terminal block be configured to pro-
vide one I 20 volt AC hot leg for the vessels distribution
panel. This will ensure good motor starting response from the
generator.
31
Generator Maintenance
• Maintaining reasonable cleanliness is important.
Connections of terminal boards and rectifiers may become
corroded, and insulation surfaces may start conducting if
salts, dust, engine exhaust, carbon, etc. are allowed to
build up. Clogged ventilation openings may cause
excessive heating and reduced life of windings.
• For unusually severe conditions, thin rust-inhibiting
petroleum-base coatings, should be sprayed or brushed
over all surfaces to reduce rusting and corrosion.
• In addition to periodic cleaning, the generator should be
inspected for tightness of all connections, evidence of
overheated terminals and loose or damaged wires.
• The drive discs on single bearing generators should be
checked periodically if possible for tightness of screws
and for any evidence of incipient cracking failure. Discs
should not be allowed to become rusty because rust may
accelerate cracking. The bolts which fasten the drive disc
to the generator shaft must be hardened steel SAE grade
8, identified by 6 radial marks, one at each of the 6
comers of the head.
• The rear armature bearing is lubricated and sealed; no
maintenance is required. However, if the bearing becomes
noisy or rough-sounding, have it replaced.
• Examine bearing at periodic intervals. No side movement
of shaft should be detected when force is applied.If side
motion is detectable, inspect the bearing and shaft for
wear. Repair must be made quickly or major components
will rub and cause major damage to generator.
CARBON MONOXIDE DETECTOR
WESTERBEKE recommends mounting a carbon monoxide
detector in the living quarters. Carbon Monoxide, even in
small amounts is deadly.
The presence of carbon monoxide indicates an exhaust leak
from the engine or generator or from the exhaust
elbow/exhaust hose, or that fumes from a nearby generator
are leaking in your area.
If carbon monoxide is present, ventilate the area with clean
air and correct the problem immediately!
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