check => 2 LG =2; LGCountry=2

How it works : Operation description


Animation Video : NO-BREAK KS® intervention during power outage



Operation description of a diesel rotary UPS system : conditioning mode

Conditioning Mode

In conditioning mode, when the mains supply is within tolerance, the synchronous machine is acting as a motor, driving the main shaft and thus the accumulator, storing kinetic energy in it.

When the inner rotor rotates at 1500 rpm (50 Hz) or 1800 rpm (60 Hz), the outer rotor then rotates at maximum 3000 rpm. The kinetic energy is thus stored.

99% of the time or more, the NO-BREAK KS® operates in conditioning mode and guarantees the supply of a clean electrical, and conditioned power to the load.

↑ Top


Operation description of a diesel rotary UPS system : independent mode

Independent Mode  

In independent mode--during mains failure or voltage perturbation--the stored kinetic energy is now transferred to the stato-alternator, which acts as a generator. This happens without any interruption to the user.

Shortly after, the diesel engine starts and couples to the stato-alternator by latching the electromagnetic clutch. The energy is then relayed from the diesel engine to the synchronous machine and then to the loads.


Sequence : 

  • QD1 opens
  • The kinetic energy transfered from the outer rotor maintains the frequency at 50 Hz (or 60 Hz) within +/- 1%
  • The engine starts
  • The electromagnetic clutch closes
  • When the engine reaches 1500rpm (1800 rpm for 60 Hz), it transfers power to the load, until the mains supply returns.

↑  Top

Transfer From Conditioning Mode To Independent Mode 

Transient Period - NO-BREAK KS


This graph shows the transfer from conditioning to independent mode and back: The frequency is maintained within narrow tolerances, the accumulator’s speed decreases and then the diesel engine starts to provide power to the load.

In the event of a diesel engine start-up failure, the electromechanical clutch will close shortly after opening QD1 and the kinetic energy of the accumulator will start the diesel engine. This gives the NO-BREAK KS® a redundant start possibility; a second guarantee to start the engine.

The NO-BREAK KS® is the only system available on the market that guarantees the start of the diesel engine.

 ↑ Top

Mains Return : Back To Conditioning Mode   

  •  The NO-BREAK KS®‚ synchronises with the mains supply.
  •  The outer rotor is re-accelerated to its rated speed.
  •  When the rated kinetic energy is stored, QD1 closes.
  •  The electromagnetic clutch opens.
  •  The diesel engine runs at idle speed for cooling and then stops eventually.

The system secures the critical load against an unlimited number of repeated mains failures.