Posted October 8, 2015

Combine Differently Sized Generators With Kohler's New Mobile Paralleling Box

Kohler Power Systems' new Mobile Paralleling Box lets users parallel generators of different sizes and fuel types. The new paralleling box, specifically designed for use with Kohler’s gaseous and diesel mobile generator line, allows flexibility and customization for generator applications, said Anne Feudner, product manager for Kohler Power Systems. 

kohler mobile parallelingFour of the new boxes can be used to parallel as many as eight generators. The Kohler Decision-Maker 3500 digital controller, which is standard on all Kohler gaseous and Tier 4 Final diesel mobile generators, provides the paralleling intelligence and network communications for remote monitoring. 

The system makes it possible to parallel generators for applications such as using multiple smaller units to replace a larger generator, providing redundancy to a primary generator in support of critical loads, meeting system capacity demands when one generator is inadequate, or managing generators to be sequenced on or off in a predetermined order based on system output.

The new system uses contactors to connect to the bus and eliminates the need for installing or investing in motorized breakers on generators that may never be used in a parallel application. Each contactor is rated at 1,000 amps – different sized generators can parallel as long as each unit’s output is less than 1,000 amps. 

Color-coded camlocks for input and output feeds make the new box easy to setup and maintain while unused camlock connectors are protected with lockable security bars. The system also includes two 25-inch control cables as well as lockable storage for control cables.  

Paralleling intelligence is incorporated into the Kohler Decision-Maker 3500 digital controller, which provides system monitoring and diagnostics while also offering a user-friendly display. The advanced digital controller uses a patented hybrid voltage regulator and unique software logic to manage alternator thermal overload protection features that normally require additional hardware. Paralleling functions featured on the controller include:

  • Bus sensing for accurate metering and control
  • First-on logic – starts all generators to allow the first generator to reach rated voltage to close to the bus
  • Synchronizing adjusts other generators’ engine speed and voltage to allow them to connect to the bus
  • External-controlled load sharing via analog bias signals
  • Load management to ensure the generators are not overloaded