Cummins OTPC Transfer Switch

Cummins SwitchOTPC transfer switches are designed for operation and switching of electrical loads between primary power and standby generator sets. They are suitable for use in emergency, legally required and optional standby applications. The switch monitors both power sources, signals generator set startup, automatically transfers power, and returns the load to the primary power source when the utility returns and stabilizes.

OTPC transfer switches are available with closed transition transfer. By briefly connecting the two sources (for 100 msec or less), the transfer from the alternate source back to the normal source occurs without interruption in the power supply to loads.


  • Easy service and access
  • Wide range of accessories and services available

  • Models and Ratings
  • Standard Features
  • Documents
  • Warranty

Model Ratings

Models Ampere Rating Transition Type
OTPCA 40 - 4000 Open (In-Phase) and Open (Delayed)
OTPCB 40 - 4000 Open (In-Phase) and Open (Delayed)
OTPCC 40 - 4000 Open (In-Phase) and Open (Delayed)
OTPCD 40 - 4000 Open (In-Phase) and Open (Delayed)
OTPCE 40 - 4000 Open (In-Phase) and Open (Delayed)
OTPCF 40 - 4000 Open (In-Phase) and Open (Delayed)
OTPCG 40 - 4000 Open (In-Phase) and Open (Delayed)
OTPCH 40 - 4000 Open (In-Phase) and Open (Delayed)


  • PowerCommand® control - A fully featured microprocessor-based control with digital display. Controls allow operator to enter settings and make adjustments to software-enabled features easily and accurately. Accommodates up to eight event schedules.
  • Programmed transition - Open transition timing can be adjusted to completely disconnect the load from both sources for a programmed time period, as recommended by NEMA MG-1 for transfer of inductive loads.
  • Advanced transfer switch mechanism - Unique bi-directional linear actuator provides smooth, continuous transfer switch action during automatic operation.
  • Robust control system design - Optically isolated logic inputs and isolation transformers for AC power inputs provide high-voltage surge protection.
  • Main contacts - Heavy-duty silver alloy contacts with multi-leaf arc chutes are rated for 100% load interruption. They require no routine contact maintenance and provide 100% continuous current ratings.
  • Communications capability - The transfer switch is capable of communicating with other transfer switches, SCADA and remote monitoring systems, or Cummins Power Generation generators utilizing LonWorks® protocol.
  • Easy service/access - Single-plug harness connection and compatible terminal markings simplify servicing. Access space is ample. Door-mounted controls are field-programmable; no tool is required.
  • Complete product line - Cummins Power Generation offers a wide range of equipment, accessories and services to suit virtually any backup power application.

Warranty and service: Backed by a comprehensive warranty and worldwide distributor network.