Firmware Regulates Water Pressure System

Pressurizers increase water pressure at the point of use and accommodate changes in system flow rates, allowing for correct operation of devices such as flush valves, dishwashers, washing machines and shower heads. Accurate control of pressure is critical for these products, as the resulting efficiency of the system is a key selling point.

Thrush Co. manufactures a range of heating and cooling products, including pumps, heat exchangers, valves, fittings and accessories for residential, commercial and industrial applications. The company has now developed an energy-saving water pressure booster system based on a Baldor variable frequency microdrive and high efficiency motor. For the Pressurizer-VS™ product line, Thrush designed a pump control system with an exceptionally narrow pressure deadband to eliminate temperature fluctuations in mixing valve applications. Power consumption was reduced, to keep users’ running costs as low as possible.

Baldor’s VS1 MD drive is suited to Thrush’s water pressure booster system due to its controllability and efficiency.

The Pressurizer-VS system provides supplemental pressurization of water supplies using a preemptive control scheme that uses Baldor-developed firmware to regulate output flow and pressure efficiently and accurately.

In the setup, a TV2g in-line pump is close-coupled to a vertically mounted motor; an adjacent hydro-pneumatic pressure tank enables the system to react instantly when water is demanded. (In the setup, a TV2g in-line pump is close-coupled to a vertically mounted motor. With the adjacent hydro-pneumatic pressure tank, the system instantly reacts to water demand.) This arrangement also prevents the system from cycling during small infrequent demands. The physical layout of the entire system is compact, so the unit can fit in areas too small for conventional systems.

The pressurizer is available with a number of motor and drive options, covering flow rates up to 200 gpm and pressure boost ranges from 30 to 80 psi. As standard, the system is supplied with a Baldor high-efficiency drip-proof motor, controlled by a Baldor VS1MD microdrive.

Aaron Schipper, applications engineer at Thrush, noted that the variable frequency drives were chosen primarily because of their controllability and efficiency. “The drives’ V/Hz control mode lets us regulate output pressure accurately, and their sleep and wake-up functions help minimize energy consumption,” Schipper said.

Thrush’s Pressurizer-VS water pressure booster uses a Baldor variable frequency microdrive and high efficiency motor to achieve high controllability and efficiency.

Baldor created custom versions of the sleep and wake-up functions, so they can be invoked directly by pressure transmitter signals. Schipper explained that on the Pressurizer-VS, the hydro-pneumatic tank is pre-pressurized immediately prior to no-flow shutdown, so that the system is always ready to respond to demand.

Thrush also makes use of the drive’s soft-start capabilities, to eliminate any power spikes on start-up.

Thrush Co.
www.thrushco.com

Baldor Electric Co.
www.baldormotion.com

::Design World::