Generator Information - Westerbeke 8.0KW - 60Hz Operator's Manual

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
commonly 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. Thc 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 con-
nected to
medium
starting loads
will
be approximately as
follows:
MOTOR SIZE
(HP)
1/6
AMPS FOR
RUNNING
(AMPERES
3.2
1/4 4.6
AMPS FOR
STARTING
(AMPERES)
6.4
to
22.4*
1 _ _ _ _ ······ _ _
--+ ____ 10_.2_ ... _ _
+---=:.:..:...:~:.::.......
_
__l
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, turn
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
generator's capacity, and finally loaded to its full capacity as
indicted on the generator's 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 amprobe.
NOTE:
When the vessel in which the generator is installed
contains AC equipment of 120 volts only, it is recommended
that the generator's AC temzinal block be configured to pro-
vide one 120 volt AC hot leg for the vessel's distribution
panel. This will ensure good motor starting response from the
generator:
GENERATOR FREQUENCY ADJUSTMENT
Frequency is a direct result of engine/generator speed, as
indicated by the following:
• When the generator is run at
1800
rpm, the AC voltage
output frequency is
60
Hertz.
• When the generator is run at 1500 rpm, the AC voltage
output frequency is
50
Hertz.
Therefore, to change the generator's frequency, the genera-
tor's drive engine's speed must be changed along with a
reconfiguring of the AC output connections at the generator.
GENERATOR MAINTENANCE
• Maintaining reasonable cleanliness is important.
Connections of tenninal 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 exces-
sive 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 cor-
ners 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 vessels 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 vessel
are entering your boat.
If carbon monoxide is present, ventilate the area with
clean air and correct the problem immediately!
Engines & Generators
36