Woodstock W1823 manual System Grounding, Flex-hose grounded to Machine Plastic Blast

Model W1823 (Mfg. Since 9/10)

System Grounding

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. 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 electric service panel.

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

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 (Figure 29) 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.

Ensure that the entire system is grounded. If using plastic blast gates to direct air flow, the grounding wire must be jumped (Figure 30) 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 the dust collector frame with a ground screw, as shown in Figure 29. Ensure that each machine is continuously grounded to the grounding terminal in your electric service panel.

Internal	External
Ground	Ground Wire		OPERATIONS
Wire		Ground Screw
Flex
Hose

Figure 29. Flex-hose grounded to

machine.

	Plastic
	Blast
	Gate
Copper	Metal Duct
Ground Wire

Figure 30. Ground jumper wire when using

plastic blast gates and metal duct.

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