Rockwell Automation 2090 Ultra3000 Installation Manual User Manual
Page 33
Publication 2098-IN003E-EN-P — April 2004
Installing Your Ultra3000
1-9
Example: sizing a transformer to the voltage requirements of an
2098-DSD-020 and MPL-A320P motor:
The speed/torque curve information for 230V motors is based upon
an Ultra3000 input voltage of 230V ac. For a 115V ac input voltage, the
maximum speed can be reduced up to one half.
IMPORTANT
If you are using the Rockwell Automation/
Allen-Bradley system sizing program, the average
speed and average torque data has already been
calculated and can be used in the above equation. If
you are not sure of the exact speed and torque in
your application, another approach is to look at the
speed/torque curve for your Ultra3000/motor
combination and use the values for the worst case
continuous speed and torque.
IMPORTANT
Calculations are multiplied by a factor to compensate
for the power and loss elements within a power
system. A factor of 2.0 is used with a single phase
system and a factor of 1.5 is used with a three phase
system. This factor should minimize the effects of the
secondary line voltage sagging in the transformer
during peak current periods.
Intro
Intro
Intro
Intro
Intro
Intro
Intro
Intro
Intro
Intro
Intro
KVA
Speed RPM
(
)xTorque lb in
–
(
)
63 025
,
-------------------------------------------------------------------------------------x
746Watts
HP
---------------------------x
KVA
1000Watts
------------------------------x2.0
=
KVA
5 000 RPM
(
)
,
(
)X17.7 lb in
–
(
)
42 250
,
--------------------------------------------------------------------------------
=
Transformer Size
2.1 KVA
=