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Frequency Controlled Drive Systems

Frequency inverters  have become an important element in the field of drive systems enabling configurations with stepless speed control from zero rotations up to the rated speed.In the field of drive motor control systems RRR Electronics provides solutions with integrated frequency converters especially designed for sophisticated pump systems such as cargo pumps, ballast pumps, jet and gland-water pumps as well as similar applications.

Modern, highly developed pump systems call for the need to maintain the highest possible discharge or flow rate while keeping all system conditions such as the pressure values on the suction and discharge side of the pump within the permitted limits.Other systems demand a continuos supervision of the actual flow rate or the mechanical and thermal strain (i.e.vibrations, cavitation, structure born noise).

Integrated control function

An integrated Programmable Logic Computer (PLC) observes the relevant system conditions such as the pressure values on the suction side of the pump and controls the drive motor speed according to the programmed limits.

The software of the PLC is specially designed for the different requirements within the ship’s system and the relevant pumps. An automatic control mode which will keep the discharge or flow rate at the highest possible level while preventing dangerous cavitation can be provided and will be adapted for the different demands on site.

The following advantages can be obtained for all application of variable frequency drive control pump speed: