Note: When calculating static pressure loss to determine if multiple lines can be left open at the same time, only include the main line numbers once.
5.Compare the total static pressure loss for that line to the maximum static pressure loss found on the data sheet for your machine (located toward the front of this manual).
—If the CFM for your static pressure loss is above the requirement of the machine, then the line will most likely be successful. Congratulations! You've just designed your own dust system. Refer to Page 30 to start buying the components necessary to make your system a reality.
—If the CFM for your static pressure loss is below the requirement of the machine, then that line will not effectively collect the dust. You must then modify some of the factors in that line to reduce the static pressure loss. Some of the ways to do this include 1) installing larger duct, 2) reducing amount of flexible duct used, 3) increasing machine dust port size, 4) moving machine closer to dust collector to eliminate duct length, and
5)reducing 90˚ elbows or replacing them with 45˚ elbows.
System Grounding
Since plastic hose is abundant, relatively inex- pensive, easily assembled and air tight, it is a very popular material for conveying dust from woodworking machines to the dust collector. We recommend using flexible hose (flex-hose) to connect the woodworking machine to the dust collector. However, plastic flex-hose and plastic duct are an insulator, and dust particles moving against the walls of the plastic duct create a static electrical build up. This charge will build until it discharges to a ground. If a grounding medium is not available to prevent static electrical build up, the electrical charge will arc to the nearest grounded source. This electrical discharge may cause an explosion and subsequent fire inside the system.
To protect against static electrical build up inside a non-conducting duct, a bare copper wire should be placed inside the duct along its length and grounded to the dust collector. You must also confirm that the dust collector is continuously grounded through the electrical circuit to the elec- tric service panel.
If you connect the dust collector to more than one machine by way of a non-conducting branching duct system and blast gates, the system must still be grounded as mentioned above. We recom- mend inserting a continuous bare copper ground wire inside the entire duct system and attaching the wire to each grounded woodworking machine and dust collector.
Always guard against static electrical build up by grounding all dust collection lines.
