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Copyright © 2012 Kato Engineering, Inc. All rights reserved
Foot defl ection
After alignment, check for foot defl ection or “soft foot” condition on
each shim location to eliminate distortion of the generator frame. Do
this by loosing one mounting bolt at a time and checking defl ection
after retightening. Defl ection at the shim location from shims under
compression to a loosened condition must not exceed 0.003 inch.
Doweling
In case the mounting bolts loosen during operation, doweling will
prevent movement of the generator. Dowel as follows:
Check the alignment after the generator has been in operation for at least
48 hours. If alignment is not satisfactory, realign.
Drill holes through the footpads and into the base in two mounting pads
opposite each other. Drill the holes slightly smaller than the dowel pin.
Ream the holes to the proper diameter for the pin. Clean out chips, and
install the pins.
Electrical connections
If the generator was subjected to a rapid change in temperature, freezing
or wet conditions during shipment or storage, measure the insulation
resistance of each winding and dry the generator, if necessary, as
described in the maintenance section below.
Make all electrical connections (main load, temperature monitoring
device, space heater, AVR) in accordance with local regulations and
national/international electrical code requirements. Check the electrical
diagrams provided with the generator or manual. The main terminals
need to be properly spaced for the load connections. Refer to Table 3 for
the proper torque values for the connections.
On larger generators grounding points are provided for properly
grounding the system to the generator frame. The grounding wire must
be sized to national/international code requirements.
Space heaters
When the generator has optional space heaters to prevent water
condensation during long periods of downtime, connect the space heaters
so they start when the generator is turned off and stop when the generator
is switched on. Some generators with space heaters have thermostats.
The thermostat should be set above the dewpoint. Refer to the electrical
diagrams for the space heater characteristics.
NOTICE: Alternator current machines are
intended for continuous operation with
the neutral at or near ground potential.
Operation with one line at ground potential
should be done only for infrequent periods
of short duration, for example, as required
for normal fault clearance.
CAUTION: The space heaters
are designed to be energized when the
generator is shut down. They are hot
enough to cause skin burns. Terminals for
power at the space heaters are live during
operation. Disconnect power to the space
heaters before removing the generator
covers.