Your choice of filter system, as well as the filter media, is usually based on the type of dust you work with — that is, whether it’s fine or coarse.
You’ll also want to consider how the filter system will be cleaned. Many filters on portable units are called “shaker type,” which means — just as it sounds — you have to remove and physically shake the filter to clean it.
A few quick notes on shakers:
- Side-to-side shaking is generally considered more effective, albeit more difficult to achieve, than up-and-down shaking.
- Unless your filters are designed to work efficiently until your material canister is full, you’ll need to power off the system periodically and clean the filters.
- Some cleaning systems automatically shut down the system, shake the filters and restart, while others use pulse jet cleaning or reverse air filter cleaning.
- The usefulness and efficiency of the cleaning system varies from system to system.
When it comes to portable vacuums with cartridge type filters, pulse cleaning systems are used most often. Cartridge type filters are very easily clogged and have to be cleaned often. Keep in mind that pulse cleaning is not a continuous method, meaning you have to shut the system down, connect it to plant air, and then manually pulse clean it.
If you have very fine dust in your work areas, we recommend staying away from cartridge systems. Many of them work poorly, and some models even require that you physically remove the cartridge and clean it yourself.
One last note: pay attention to the vacuum’s “can velocity”, which refers to the upward flow of air through a filter cartridge. If the velocity exceeds 125 fpm, the filters will easily clog, and they typically won’t be easy to clean.
