Generators
with sealed windings in weather-protected enclosures
can replace totally enclosed machines at a reduced
overall cost and with improved performance.
Smaller and lighter: Because generators
with weather-protected enclosures do not require a
secondary air exchange, they are smaller and lighter.
Typical output derating ranges from 30 to 40 percent
of open drip proof construction to make a synchronous
machine totally enclosed. For example, in the 4,000
kW rating, the totally enclosed machine requires a
one size larger frame than the open machine.
More efficient: Generators with sealed
windings and weather-protected enclosures are more
efficient than totally enclosed designs. Assuming a
kilowatt hour costs $0.04 and a typical average load
is 75 percent, the savings due to increased
efficiency for a 960 and 4,000 kW machine is $1,500
per year and $12,000 per year respectively. This
represents almost five percent of the total cost in
the first year of operation.
Less complicated: Weather-protected enclosures
are less complicated than totally enclosed designs.
This is important during servicing. In some cases,
replacing the bearing on a totally enclosed machine
may require removing the entire cooler assembly with
brackets.
No enclosure seals to rely on: With totally
enclosed designs, seals (such as those used to seal
the shaft, lead entrance, and terminal boxes) will
eventually wear out and cause environmental
contamination, leading to more costly disassembly for
cleaning.
Features: Kato generators with
weather-protected enclosures and sealed windings are
designed and manufactured for a minimum service life
of 20 years. These generators will provide excellent
service in adverse environments.
• Withstands water immersion test per NEMA
MG1-20.49 & API 546
• Uniform and precise coils to alleviate void
pockets
• Sealed windings and connections
• Multi vacuum-pressure impregnation and cure
process
• Smaller, lighter and more efficient than totally
enclosed units
• Designed for easy maintenance
