Patent ID: 9302130
Filing Date: 2016-04-05
CPC Classification: A62C,F04B,F04D

Claim Text:
1. Control method for the electric motors of a pump unit of a fire protection system, which fire protection system comprises spray nozzles ( 112 ), a pump unit, a control system with pressure-measuring mechanism, and piping ( 105 ) for conducting extinguishing medium from the pump unit to the spray nozzles, which pump unit comprises a plurality of pump drives, each of which comprises a pump ( 101 ) and an AC electric motor ( 102 , 203 a - 203 f ) configured to rotate the pump, the AC electric motor being connected to an AC electricity network via a contactor device ( 206 a - f ), in which the AC electric motors are controlled on the basis of a pressure measured in the piping, characterized in that a first electric motor of the electric motors ( 102 , 203 a - 203 f ) at a time is controlled by a frequency converter ( 108 , 204 ) such that the first electric motor under the control of the frequency converter steplessly adjusts pressure and the others of the electric motors are started up into the AC electricity network as steplessly adjusting motors; and the pump unit is controlled via a separate control unit, common to the electric motors and to the frequency converter, the control unit comprises a control unit card (PUC) ( 402 ) for the pump unit, connection boards (MCI) ( 403 ) for the motor control, a connection board (FCI) ( 404 ) for frequency converter control, and input/output cards (IOC) ( 405 ), wherein time-critical commands, including a synchronization command, open the network directly (KF), close the frequency converter (KD), are generated locally in the connection boards (MCI) ( 403 ) for motor control, a connection board (FCI) ( 404 ) for frequency converter control.