System Grounding - Grizzly G0440 Owner's Manual

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 stat-
ic electrical build up by
grounding all dust collec-
tion lines.
-34-
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 ground-
ing wire must be jumped (see the Figure below)
around the blast gate without interruption to the
grounding system.
Plastic Blast
Copper
Ground Wire
Figure 52. Ground jumper wire when using
plastic blast gates 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 to the dust
collector frame with a ground screw as shown in
the Figure below. Ensure that each machine is
continuously grounded to the grounding terminal
in your electric service panel.
External
Ground Wire
Internal
Ground Wire
Flex-Hose
Figure 53. Flex-hose grounded to machine.
Model G0440/G0441 (Mfg. Since 03/12)
Gate
Metal Duct
Ground
Screw