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Light-Duty Roto-Phase III

Rotary Roto Phase Converter Light

The Light Duty series converter is designed for "one" single three-phase motor, which is easy starting and ran under a light load condition. This unit delivers 100% of the three phase motor horsepower, and it is comparable to our competitor's general duty and sometimes heavy duty rated units.

Model Largest Motor
ST2 2
ST3
ST5 5
ST7
ST10 10
ST15 15
ST20 20
ST25 25
ST30 30
ST40 40

The Light duty Roto-Phase is designed for easy starting applications, where only one or two motors are operated. The Light-Duty Series delivers 100% of the three-phase motor horsepower rating for applications such as: centrifugal pumps, drill presses, saws, grinders, etc. For harder starting applications such as air compressors, hydraulic presses, oil well pumps: a hard start kit may be necessary. The Light-Duty Roto-Phase is designed to operate one motor equal to the largest motor rating, plus smaller motors to obtain the total horsepower capacity of the Roto-Phase. All models are rated in horsepower, with specific ratings of : "largest Motor HP" & "Total HP Capacity". The larges motor horsepower rating is in true horsepower, and is not intended to operate mis-rated motors or motor loads. For applications assistance consult our factory.

Model Notes:

* Paralleled Units

  • O.D.P. or T.E.F.C. Design Available.
  • Total horsepower capactiy may reach 1.5 to 2 times the larges motor HP catagory.
  • Specify 230 VAC or 460 VAC.
  • High Torque start kit availible, consult factory.
  • Larger models available, consult factory.
  • Refrigeration Equipment/Welders are sized by FLA/INPUT Amperes, consult factory.
  • CAUTION: For foreign motor designs, 2-speed windings, instant reverse applications, consult factory.
Rotary Roto Phase Converter Diagram

Roto-Phase Accessories from ARCO

  • Starters
  • Fuses
  • Disconnects
  • Motor-Servers
  • Items sold separately or as a package with Standard-Duty Roto-Phase Models.
SPECIFICATIONS: Approx.
Ship Wt.
Models A B C E F G H L M O P CC DD OO T
ST2 8.50 6.50 10.50 3.75 2.812 .38 .437 5.25 5.25 8.25 7.75 3.875 6.25 12.00
60
ST3 8.50 6.50 12.00 3.75 2.750 .38 .437 6.00 6.00 8.25 7.75 3.875 6.25 12.00
64
ST5 9.50 8.00 13.75 4.25 3.500 .49 .406 6.875 6.875 10.06 9.56 4.780 8.00 15.56 2.375 135
ST7 11.24 10.07 16.25 5.00 4.120 .60 .562 9.40 6.56 12.53 12.56 6.280 8.00 20.56 3.000 140
ST10 11.24 11.57 17.50 5.00 5.000 .60 .562 10.15 7.31 12.53 12.56 6.280 8.00 20.56 3.000 200
ST15 12.58 12.94 32.50 6.50 5.500 .25 .531 9.84 9.84 14.64 13.75 6.875 8.00 21.75 1.930 220
ST20 14.56 13.44 32.50 6.25 6.000 .34 .656 10.28 10.28 16.64 15.75 7.280 8.00 23.75 1.930 380
ST25 14.56 14.94 32.50 6.25 6.00 .34 .656 11.03 11.03 16.64 15.75 7.280 8.00 23.75 1.930 385
ST30 16.19 14.12 32.50 7.00 5.620 .34 .656 11.16 11.16 18.44 17.31 8.095 8.00 25.31 3.140 465

Dimensions given are not certified.
Case size and shipping weights are subject to change without notice.
ARCO Electric reserves the right to make product changes without prior notice.
Specify 230 V or 460 V. Orders placed without specified voltage 230 will be used.

How to Specify:

For Manual Models: "3-Phase motors shall be powered from a single phase source by a multimotor rotary phase converter (single to three phase) equal to ARCO Roto-Phase Model: _____, Voltage: _____, as manufactured by ARCO Electric Products Shelbyville, Indiana with a 5-year warranty or approved equal."

Contact ARCO

Home Office:
2325 E. Michigan Road
Shelbyville, IN 46176-3400
Toll Free: 800-428-4370
Direct: 317-398-9713
Fax: 317-398-2655
Location Manager:
E-Mail: Hal Pike
Sales Manager:
E-Mail: Tim Drake