Skip Navigation

PDF Version


Rotary Roto Phase Converter CNC - 2013
+ 1 PH POWER =
Rotary Roto Phase Converter CNC2 - 2013

Standard Features:

  • Voltage Balance Within 2% or Less Under All Loading Conditions
  • Heavy Duty Construction
  • Continuous Duty Cycle
  • Available In ODP or TEFC Design
  • Easy Installation

The “CNC Series” converter was developed in the early 1980’s when CNC (Computer Numerical Controlled) equipment began to flood the machinery market. Most standard or heavy duty phase converters on the market are not capable of providing the variable speed drive motors on the three-phase equipment with the adequate voltage supply required to operate this type of machinery. The CNC series phase converter is able to provide a stable “phase-to-phase” voltage condition which is between 1-2% under all loading conditions on the three-phase equipment. Unlike our competitors, who use transformers or capacitor switching via manual switches and contactors, the CNC series converter does not depend upon these types of devices which could pose a potential maintenance concern. The CNC series Roto-Phase converter has been field tested and proven reliable for years. It is truly unlike any rotary phase converter on the market because of its capabilities to deliver good starting torque and necessary voltage tolerances of 5% or less to the three-phase equipment load. From precision work on CNC machine tool and EDM equipment to lasers used for eye surgery, the CNC Roto-Phase converter is the most reliable unit on the market. When three-phase power is not available from the utility company or is not economically feasible, then the ARCO Roto-Phase is the best substitute. CNC Roto-Phase models are available from 1 HP to 50 HP sizes. FOR LARGER SIZES PLEASE CONSULT FACTORY

Note: A single-phase “buck & boost” transformer may be required for use in conjunction with the phase converter & three-phase equipment, when the single-phase voltage from the utility company is higher than the voltage tolerance requirements for the three-phase equipment. CONSULT THE FACTORY


  • Magnetic Starter With Overload Protection (Push Button Start/Stop or Automatic Option)
  • Fused Disconnect
  • Surge Arrestor
Rotary Roto Phase Converter Diagram
Ship Wt.
CNC1 13.00" 11.00" 10.00" 7.00" 9.00" 10x8x6 95 Lbs.
CNC2 16.00" 13.00" 13.00" 8.00" 10.00" 16x12x6 159 Lbs.
CNC3 17.00" 14.00" 13.00" 10.00" 12.00" 16x12x6 239 Lbs.
CNC5 19.00" 16.00" 16.00" 12.00" 12.00" 18x18x10 285 Lbs.
CNC7 23.00" 18.00" 21.00" 13.00" 13.00" 18x18x10 365 Lbs.
CNC10 25.00" 20.00" 24.00" 14.00" 15.00" 18x18x10 448 Lbs.
CNC15 27.00" 22.00" 25.00" 15.00" 17.00" 18x18x10 703 Lbs.
CNC20(**) 25.00" 20.00" 24.00" 14.00" 15.00" 18x18x10 950 Lbs.
CNC25(**) 25.00" 20.00" 24.00" 14.00" 15.00" 18x18x10 1318 Lbs.
CNC30(**) 27.00" 22.00" 25.00" 15.00" 17.00" 18x18x10 1412 Lbs.
CNC40(****) 25.00" 20.00" 24.00" 14.00" 15.00" 18x18x10 1792 Lbs.
CNC50(****) 25.00" 20.00" 24.00" 14.00" 15.00" 18x18x10 2636 Lbs.
CNC60(****) 27.00" 22.00" 25.00" 15.00" 17.00" 18x18x10 2812 Lbs.

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.

(**)Two Units Paralleled (***) Three Units Paralleled (****)Four Units Paralleled

With the addition of optional features, the panel size of the phase converter model may change – Please Consult Factory.

ARCO Electric Products reserves the right to make product changes without prior notification.

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
Plant Manager:
Tony Abdou
Customer Service:
Tim Drake
Customer Engagement Supervisor:
Marcia Krise