Woodstock W1816 owner manual System Grounding, Metal Duct

W1816 Owner's Manual (Mfg. Since 10/09)

System Grounding

OPERATIONS

Since plastic hose is abundant, relatively inexpensive, easily assembled and air tight, it is a very popular material for conveying dust from woodworking machines 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 electric 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 recommend inserting a continuous bare copper ground wire inside the entire duct system and attaching the wire to each grounded woodworking machine and dust collector.

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” connection.

ALWAYS guard against static electrical build-up by properly grounding all dust collection lines.

Plastic Blast

Gate

Copper

Ground

Wire

Metal Duct

Figure 50. Jumper wire connected to both

sides of a plastic blast gate and metal

ducts.

Ensure that the entire system is grounded. If using plastic blast gates to direct air flow, the grounding wire must be jumped (see Figure 50) around the blast gate without interruption to the grounding system.

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 to the dust collector frame with a ground screw as shown in Figure 51. Ensure that each machine is continuously grounded to the grounding terminal in your electric service panel.

Flex	Ground
Hose	Screw
External Ground Wire
Internal Ground Wire

Figure 51. Example of a plastic flexible

hose grounded to the machine.

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