Cascading water pumps ensures best availability
The cascade pump control available with IMO Jaguar VXA (Aqua) range has been specifically designed in close consultation with water industry experts worldwide to fulfil the exacting requirements of the industry. The drives offer reduced downtime, reduced energy usage and reduced wastage/seepage.
With features, such as anti-jamming, dry pump detection, and reduce start-up stresses on both the pumps and the system. Linearization reduces excessive terminal pressures during periods of low flow and the soft pressurising features reduce pipe bursts, water seepage and general stresses on the system.
Up to 90 kW they include an integral EMC filter and DC reactor and a choice of either IP21 or IP55 construction. Larger ratings from 110 kW to 710 kW also include external EMC filter and DC reactors and are available in IP00 construction.
Pumping stations and pressure boosting stations
With cascading pump control, 4 built in PID controllers, dry pump detection, condensation prevention and linearization functions the VXA is ideally suited to this type of application. With the built in-PLC and real time clock functions and multitude of communication options the drive can be installed as part of a system or used as a stand-alone controller.
Cascade Control
Cascading pump control is the function that controls multiple pumps with one inverter. The pumps are controlled with a combination of inverter drive and mains driven motors depending on the flow rate required.
The signals of flow rate and pressure sensors are controlled by the PID controller built into the inverter. Each pump is driven either by the inverter or mains driven motor according to the switching signal from the inverter. The pumps are controlled only by the inverter when the discharge volume is small, the inverter then starts extra pumps one by one by one as the discharge volume increases to maintain the required discharge volume. There are two different methods of control, fixed and floating control methods.
1. Mono-regulated pump control (Fixed)
Maximum configuration is one inverter driven pump, up to eight mains driven motors, plus one auxiliary motor
The system for this method is configured by combining the motor driven by the inverter (M0), motors that are mains driven (M1 to M8) and auxiliary motor (MA). The motor driven by the inverter is always fixed as motor M0. Mains driven motors are added one by one when the required discharge flow rate cannot be achieved with motor M0 only.
2. Multi-regulated pump control (Floating)
Maximum configuration four inverter driven pumps. Additional pump is added / removed depending on the regulated pump speed and if others are also enabled or not.
The system for this method is configured by combining the motors that can be switched between inverter drive and mains driven motor (M1 to M4) and auxiliary motor that are mains driven (MA). The motors are driven by a single inverter with variable speed control at start.
Mutual Operation
The system can be configured without using a controller by connecting the inverters via communications. In this system failure occurs to the master inverter, the next inverter is assigned as the master inverter. Wiring can be saved by using the inbuilt Modbus RTU communications.
Open IMO VXA Aqua brochure here
Download VXA pump application guide here
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