Collection System

Material Selection

You have many choices regarding dust collection ducting, but flexible hose is the most common for this size of machine. However, be aware that there is a fire or explosion hazard if plastic duct material is used for dust collection without being grounded against static electrical charge build-up.

Flexible rubber hose, polyethylene, plastic flex- hose and other flexible ribbed hose is gener- ally used for short runs. There are many different types of flex hose on the market today. These are manufactured from materials such as polyethyl- ene, PVC, cloth hose dipped in rubber and even metal, including steel and aluminum.

If using flex-hose, you should choose one of the many types that are designed specifically for the movement of solid particles, i.e. dust, grains and plastics. However, the cost of specifically designed flexible duct can vary greatly. Grizzly offers polyethylene and steel flex hose.

Always guard against static electrical build up by grounding all dust collection lines.

Duct Grounding

Plastic flex-hose is an insulator, and dust particles moving against the walls of the hose creates 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 near- est 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.

-14-

Be sure that you extend the bare copper wire down all branches of the system. Do not forget to connect the wires to each other with wire nuts when two branches meet at a “Y” or “T” connec- tion.

Ensure that the entire system is grounded. If using plastic blast gates to direct air flow, the grounding wire must be jumped (see Figure 8) around the blast gate without interruption to the grounding system.

Plastic Blast Gate

Copper Ground Wire

Metal Duct

 

Figure 8. Ground jumper wire when using plastic blast gates or elbows and metal duct.

We also recommend wrapping the outside of all plastic ducts with bare copper wire to ground the outside of the system against static electrical build up. Wire connections at Y’s and T’s should be made with wire nuts.

Attach the bare ground wire to each stationary woodworking machine and attach the dust col- lector frame with a ground screw as shown in Figure 9. Ensure that each machine is continu- ously grounded to the grounding terminal in your electric service panel.

Ground Screw

Flex-Hose

External Ground Wire

Internal Ground Wire

Figure 9. Flex-hose grounded to machine.

Model G0710 Dust Collector (Mfg. since 6/10+)

Page 16
Image 16
Grizzly G0710 owner manual Collection System, Material Selection, Duct Grounding