Why Should I Have a Ground Wire Sewn into my Bag Filter?

The filter in the picture is a filter that just came in for cleaning. The black marks are burn marks in the filter.
What caused this? Sparks built up by static electricicy jumped from the filter bag to the cage and burned the filter. This then caused the filter to melt along the wire cage. Ok, bad deal the filter is leaking. Yes, this is a pain. What could have happened is a lot worse. When the spark jumped accross the filter bag the collector could have blown up like a bomb. The filter was in a grain milling enviroment. Consider using a ground wire in your filters. If a ground wire would have been sewn into the bag the electric charge would have ran up the length of the filter and grouned out on the steel frame. Having a ground wire can prevent a a very dangerous situation. It is worth the extra couple bucks.