Duct Grounding - Grizzly G0583 Instruction Manual

There are also many kinds of pure plastic flex-
ible hose, such as non-perforated drainage type
hose and dryer vent hose. Drainage type hose,
while being economical, does not quite have the
flexibility required for dust collection. The inside
of the duct is also deeply corrugated and can
increase the static pressure loss by as much as
50% over smooth wall duct. Dryer vent hose,
while being completely flexible, is non-resistant
to abrasion and has a tendency to collapse in a
negative pressure system.
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 hose, which is well suited for
the removal of particulate matter, especially saw-
dust, since it is durable and completely flexible.
Polyethylene is also very economical and avail-
able in a wide variety of diameters and lengths for
most applications.
Plastic Rigid Duct
The popularity of plastic duct is due to the fact that
it is an economical and readily available product.
It is also simple to assemble and easily sealed
against air loss. The primary disadvantage of
plastic duct for Canister Dust collection, whether
black ABS or white PVC and even rubber or
polyethylene flex-hose, is the inherent danger of
static electrical build-up.
G0583 1 HP Canister Dust Collector

Duct 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
ducting are an insulator, and dust particles mov-
ing 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 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.
Always guard against
static electrical build up
by grounding all dust
collection lines.
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