Northern Lights Lugger M673D, Operator'S Manual

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OM673 09/09
AC Generator - TF-276M & TF-276D
21
OPERATION
In order to ensure a long, trouble-free life, the gen-
erator must be operated properly and the
specifi ed maintenance must be performed.
OPERATING ENVIRONMENT
Always keep electrical equipment clean. Moisture,
salt, dust, and oil will damage the generator. The
operating environment must be kept as clean and
moisture free as possible.
VENTILATION
Good ventilation is important for proper genera-
tor operation. When installing the generator set, be
sure the ambient temperature does not exceed 40°C
(104°F) during operation.
MAINTENANCE
Proper and effective maintenance is required to
ensure trouble-free operation. In addition to the
above items, the following are required:
1. Periodically check all bolts and nuts for proper
torque. This is especially true for coupling bolts.
2. Be sure to keep the generator area clean and dry.
a. Dust and foreign material may reduce the fl ow of
cooling air, reducing heat dissipation and causing
the generator to overheat.
b. If electrically conductive debris accumulates on
the windings, or if moisture or salt water are
absorbed into the windings, the windings may
short or ground, reducing voltage output.
c. Wiping is the only effective method for removing
dust and foreign materials. Use a clean, lint-free
piece of cloth.
3. If the generator has not been operated for an
extended period of time, check the insulation resis-
tance of each stator coil and the rotor.
Disconnect the AVR from the generator when per-
forming this test.
4. Voltage Adjustment
a. If there is some voltage, but it does not build up
to rated voltage, voltage adjustment can be made
using the “hand trimmer” in the AVR (
Figure 31
).
b. The normal voltage setting at no load is 121 volts
at 62 Hertz or 242 volts at 62 Hertz.
Figure 31: Hand Trimmer Location on AVR.
5. Check the ball bearing in the generator end.
a. Listen for unusual noise.
b. Abnormal temperature rise can be noted by
discoloration.
c. If the bearing is failing, it must be replaced.
d. Generator bearing should be replaced by your
Northern Lights dealer at 10,000 hours.
6. Check the brushes
a. The carbon brushes gradually wear with use, so
they must be inspected periodically and replaced
as necessary.
b. If the brushes are excessively worn as to expose
the pigtail (
Figure 32
), sparking will occur at the
surface of the slip ring, causing surface damage.
Therefore, periodic inspection of the brushes is
important.
c. Normally, the brushes will have to be replaced
with a new brush assembly within 3,000 hours.
Figure 32: Brush Pigtail.