The curved bar screen fully automatically filters off particles and waste from wastewater in the screen structure. It features a stainless steel switchboard including PLC which controls the screening operation.

A rake is used to clean the bar screen unit and remove the filtered off waste. The rake is activated by two hydraulic cylinders. The curved bar screen is automatically activated at variable intervals or through a level sensor, but it may also be activated manually.

The level sensor serves as an automatic safety device if the water level rises above the fixed maximum level. This may happen in case of a sudden clogging of the screen.

In such a case the level sensor will override the timer and activate the rake arm immediately to allow the screen to be cleaned and the water to flow freely again.

The bar screen rake begins its cycle in the horizontal position. The rake meshes at the scraper and the rake arm is in its top position. Here the bar screen rake is activated automatically by a hydraulic cylinder in the rake arm that pulls back the rake. When the rake has been pulled back, the pressure control signals the control unit, and the rake arm is pushed down.

When the rake arm is in the vertical position, a signal is sent to the hydraulic cylinder in the rake arm and the rake is pushed forward to mesh with the bar screen. Then the rake is pulled towards its top position and on its way it scrapes clean the bar screen. When the rake is clear of the bar screen, the rake is automatically scraped clean by the scraper and soon after the hydraulic station stops. A cycle has been completed, and after a preset period of time the next cycle begins.