Onan UF Series Instruction Manual And Parts Catalog page 60

D E S C R I P T I O N
GENERATOR. - This generator is inherently regulated and will main-
tain the output voltage within limits of 10% between no
load and full load, when driven at its nameplate speed and at normal
ambient temperature. The voltage will be somewhat higher when the
generator is cold, and will vary with the driven speed. Frequency will
vary 1 cycle for each 30 rpm of variation from rated speed according
to the curves below.
CURVES OF VARIATION OF FREQUENCY WITH SPEED
*
c
z 50
O 49
48
5 0 O
1
C L I
1
:
GE
S'ER
1 1
ATO "i
« 62
a
a . ,
u
I 59
cc
^ 58
6 3 CY C L E
1 1
CE^ •JER/ 1
1440 1470 1500
S P E E D IN RPM •
1530 1560
Fig. 1.
1740 1770 1800 1830
S P E E D IN RPM •
1860
The power factor rating for all single phase models is 100%. The power
factor rating of 3 phase models is 80%. The voltage regulation will not
be greater than 10% at full load and rated power factor.
The generator may be driven in either a clockwise or counterclockwise
direction, as installation requirements demand. The blower scroll
must be reversed whenever the generator rotation is changed. See par-
agraph on REVERSING THE SCROLL. The generator is shipped from
the factory with the scroll assembled for counterclockwise rotation.
The direction of rotation of the generator is determined while looking
at the end of the generator opposite to the drive end. The generator is
drip proof in design, but reasonable precautions should be taken against
excessive exposure to moisture.
The instruction manual covers both 1 phase 4 wire, and 3 phase 4 wire
ONAN Ball Bearing Separate Generators.
A manual field rheostat can be used with the generator if it is necessary
to operate above rated speed. It can be obtained, at added cost after
the generator is received. See "PARTS LIST" for correct part number.
It can also be used to reduce the voltage at light loads. The rheostat
can not be used to increase the voltage above what it would be without
it. See wiring diagram for proper connections.
SWITCHBOARDS. - Switchboards are optional equipment which can be
purchased at added cost. Listed in the TABLE OF
RATINGS are the Switchboard Model No. 's. They contain a voltmeter,
ammeter, circuit breaker, generator and load terminals. The switch-
board is generally used to check generator and load operation accurately
and to prevent the generator from being overloaded. The operator can