Automatic, semi-automatic or manual filtration

The filtration element of the filter will clog over time as it fills with contaminants. It will need to be cleaned to continue to operate effectively.

When this cleaning process is automated/semi-automated, it is called a back-flush. This back-flush can either be manual, semi-automatic or automatic, depending on the filter.

Manual filters

As the name suggests, manual filters require 100% manual labor to clean. There is no back-flush.
To clean the filter element, you need to stop the water supply, disassemble the filter, remove the disc or screen element, and clean it yourself. In most cases, manual filters are only suitable as backup filters where the cleaning requirement is only occasional.

Semi-automatic filters

You will most often find these filters in-field providing backup filtration. Although not fully automatic, they require much less labor than manual filters as back-flush is performed by simply opening a valve and turning a handle.

 

Automatic filters

Any farm of size should use automatic filters for primary filtration. These filters back-flush themselves automatically at set time intervals or when a pressure differential meets a determined threshold.

 

Pressure differential = the pressure difference between the inlet and the outlet of the filter. The higher the pressure differential, the more clogged the filtration element is.

 

Aside from periodic maintenance and monitoring, automatic filters do not require any intervention for operation. The filters will operate and clean as required, while also providing irrigation water during the cleaning process.

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