Specification sheet CHPC Transfer switch closed transition 125 - 800 Amp Description ® The Cummins series CHPC PowerCommand automatic transfer switch monitors the primary power source, signals the generator to start upon loss or destabilization of utility power, and then automatically transfers the load to the generator. Once the utility power source becomes available and stable, the CHPC will return the load to the primary source without power interruption by temporarily paralleling both sources for less than 100 msecs. Designed and constructed specifically for closed transition operation, this clean sheet, revolutionary design incorporates the innovative High Endurance Mechanism (HEM) for uncompromising reliability with the proven PowerCommand Microprocessor Control. UL-listed 30-cycle ratings - CHPC is listed for shorttime ratings of 25,000 amps at 10 cycles for 125-260 amps, 30,000 amps at 30 cycles for 300-600 amps, and 42,000 amps at 30 cycles for 800 amps. PowerCommand control - A standard, fully featured microprocessor-based control. Software-enabled features, settings, and adjustments are available for ease of setup and accuracy. Optically isolated logic inputs and high isolation transformers for AC power inputs provide high-voltage surge protection. Manual operation - Manual operating handles and stored energy transfer mechanism allow effective, manual operation of the CHPC. An external operator is available as an option for dead front manual operation. Manual operation of the CHPC can only be performed in the open transition transfer mode. Main contacts - Heavy-duty silver allow contacts and multi-leaf arc chutes are rated for total system transfer. Easy service/access - Plug connections, doormounted controls, ample access space, and compatible terminal markings allow for easy service. Product lines, accessories and services Cummins offers a wide range of accessories and services to suit your requirements Warranty and service - Backed by a comprehensive warranty and worldwide distributor network.

Transfer switch mechanism  CHPC has earned the industry’s highest UL-listed short-time ratings. At 480 volts, 125-260 amp switches are rated at 25,000 for 10 cycles, 300600 are rated at 30,000 for 30 cycles, and 800 is rated at 42,000 for 30 cycles.  Blow-on contactor allows for high survivability in fault current conditions.  Simultaneous make-before-break contactor action is used for 2-pole, 3pole, and 4-pole switches. On 4-pole/switched neutral switches, this action also prevents the objectionable ground currents and nuisance ground fault tripping that can result from overlapping neutral...

HEM power cassette  Cassette design ensures that all phases and neutral are switched at the same speed, providing true four pole operation.  Encapsulated contactor design increases phase to phase isolation and reduces possibility of arcing between phases.  New design eliminates a common failure point in many transfer switches by not using electrical connections made of braided metal in the mechanism’s current path.  Simple design has fewer parts reducing the mechanism’s potential for failure. The innovative design of the High Endurance Mechanism The High Endurance Mechanism (HEM) is designed...

PowerCommand microprocessor control PowerCommand controls are microprocessor based and developed specifically for automatic transfer switch operation. The control provides features and options useful for most applications. Flash memory is used to store control settings. The contents of the memory are not lost even if power to the controller is lost. There is also an on-board battery to maintain the real-time clock setting and the engine start time delay. Control features include: Level 2 control Open transition (in-phase transition) Delayed transition (programmed transition) Closed transition...

Time-delay functions Engine start: Prevents nuisance genset starts in the event of momentary power system variation or loss. Not included in utility-to-utility systems. Transfer normal to emergency: Allows genset to stabilize before application of load. Prevents power interruption if normal source variation or loss is momentary. Allows staggered transfer of loads in multiple transfer switch systems Retransfer emergency to normal: Allows the utility to stabilize before retransfer of load. Prevents needless power interruption if return of normal source is momentary. Allows staggered transfer of...

UL withstand and closing ratings The transfer switches listed below must be protected by circuit breakers or fuses. Referenced drawings include detailed listings of specific breakers or fuse types that must be used with the respective transfer switches. Consult with your distributor/dealer to obtain the necessary drawings. Withstand and Closing Ratings (WCR) are stated in symmetrical RMS amperes. UL-listed specific breaker ratings MCCB protection Current limited breaker protection Transfer switch ampere WCR @ volts max with specific manufacturers MCCBs With specific current limiting breakers...

Enclosures The wall-mounted transfer switch and control are mounted in a key-locking enclosure. Wire bend space complies with 2005 NEC. Dimensions - transfer switch in UL type 1 enclosure Depth Amp rating Door closed Door open Outline drawing Dimensions - transfer switch in UL type 3R, 4, 4x, or 12 enclosure Depth Amp rating Door closed Door open Cabinet type Outline drawing Transfer switch lug capacities All lugs accept copper or aluminum wire unless indicated otherwise. Adapters that will accept compression lugs are available for 5/16”, 3/8”, 1/2” and 5/8” mounting hardware. Compression lugs...

Submittal detail: options Amperage ratings:  C024 Switch control - Level 2 Pole configuration:  A065 Poles - 2 (solid neutral)  A028 Poles - 3 (solid neutral)  A029 Poles - 4 (switched neutral) Frequency:  A044 60 Hertz  A045 50 Hertz Application:  A035 Utility to genset  A037 Genset to genset Control options  M017 Security key - front panel  M018 Display - digital  M031 Communications - LonWorks network communications module  M022 Load monitoring (min current level 3%)  M023 Module - relay signal Meters  D009 Digital bar graph meters Battery chargers  K001 2 Amps, 12/24 Volts...