System Grounding - Grizzly T28798 Owner's Manual

Flexible Duct
Flexible hose is generally used for short runs and
at rigid duct-to-machine connections. The supe-
rior choice here is metal flex hose that is designed
to be flexible, yet be as smooth as possible inside
to reduce static pressure loss. DO NOT use dryer
vent hose because it tends to collapse.
Figure 12. Example of flexible metal duct.
Ensure Required CFM at Machine
Since each machine produces a different amount
of dust, the requirements for the minimum amount
of CFM to move that dust is unique to the machine.
Knowing this required CFM is important to gaug-
ing what size duct to use.
For best results when using the Y-inlet, we recom-
mend installing blast gates to control airflow for
each line near the Y-inlet.
Refer to Figure 13 for a close estimation of the
airflow each dust-producing machine requires.
Machines that generate the most dust should be
placed as close as possible to the dust collector.
Machine
Dust Port Size
2"
2.5"
3"
4"
5"
6"
7"
Figure 13. Approximate required airflow for
machines based on dust port size.
8"
9"
10"
-18-
Approximate
Required CFM
100
150
250
400
600
850
1200
1600
2000
2500

System Grounding

To guard against static electrical buildup, we
strongly recommend replacing any plastic dust
ports on dust-producing machines
equivalents.
If you absolutely must use any plastic duct or
components, they must be completely grounded
and bonded to the metal frame of a grounded
machine by wrapping the flex hose with an exter-
nal ground wire connected to both machines as
shown in Figure 14. Ensure that each machine is
continuously grounded to the grounding terminal
in your electric service panel.
Grounding wire bypasses
plastic components to bond
ducting to grounded machine
External
Plastic
Ground Wire Dust Port
Flex-Hose
Figure 14. Example showing how to ground and
bond ducting with a grounding wire.
Always guard against
static electrical build up
by grounding all dust
collection lines.
Model T28798 (Mfd. Since 12/18)
with metal
Ground
Screw