Water hammer is a destructive phenomenon, best described as hydraulic shock. It is caused by a sudden change in fluid motion. Because the liquid travelling through a pipe system has momentum, changing that momentum by closing a valve suddenly results in the build up of kinetic energy and, if left untreated, causes a shockwave to propagate through the pipe system. The result can be as low key as an audible bang or pipe shudder, however there is potential for more catastrophic results such as pipeline blowouts.

One cost-effective solution to water hammer is to avoid sudden changes in fluid motion. This can be achieved by reducing the flow of fluid prior to closing a valve and is where WEG’s SSW900 soft starter comes into its element. The modern soft starter controls motor torque to gently start a motor, however it’s capable of much more than a controlled start.

The technology used to gently start a pump can also be used to decelerate the pump. The SSW900 includes an algorithm, called Pump Control, which was purposefully designed to maintain a level of torque output during deceleration. This maintained torque output prolongs the deceleration and provides time for valves to be slowly activated and thus avoiding water hammer.

Combining convenience and innovation, WEG’s SSW900 is a high-performance device with integrated PLC functionality, providing fully programmable algorithms for regulating induction motors as well as fully flexible torque control. It offers a complete solution for motor start/stop control and protection. Developed for industrial or professional use, the new line of soft starters adds unfounded ease of use and application flexibility.

Featuring a full text and graphical interface, user interaction has never been more intuitive allowing simple access to configuration settings and data. Oriented Start-up provides guided step-by-step parameter configuration.

On the occasion that help is required, simply pressing the ‘Help’ button will bring up a complete description of the parameter function removing the dependence of referring to a manual.

The inclusion of a Real Time Clock allows time and date stamping of alarms and events. Being a full text display, the alarm code is followed by a fault description and critical diagnostics data captured at the time of fault, aiding in troubleshooting and reducing production downtime.

Extending the benefit of the Real Time Clock is the SoftPLC. Custom code can be written to control inputs and outputs, control process requirements, and extend the protection capabilities by creating industry specific protection features.

Whether you want a pump to start at a particular time of the day, run for a specified time, control a jacking pump or even create a dry run protection algorithm all is within the SoftPLC’s capability providing the user the ultimate in application flexibility while reducing component count and circuit complexity.

The SSW900 design includes a built-in bypass which optimises space and reduces heat dissipation in electrical panels. This leads to better efficiency of both cabinet space and electrical efficiency leading to longer term energy savings and a longer lasting product. The SSW900 from WEG offers the ultimate solution in pump control.

This sponsored editorial is brought to you by WEG. For further information, please visit

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