8’ - 24’ POWERFOILPLUS™, POWERFOIL™, & WICKERBILL FANS
WWW.BIGASSFANS.COM ©2010 DELTA T CORP. DBA BIG ASS FAN ALL RIGHTS RESERVED
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WWW.BIGASSFANS.COM ©2010 DELTA T CORP. DBA BIG ASS FAN ALL RIGHTS RESERVED
8’ - 24’ POWERFOILPLUS™, POWERFOIL™, & WICKERBILL FANS
Conduit/Piping Guidelines
The nature of Variable Frequency Drive systems must be considered prior to and during the installation of Big Ass Fans. Due to high
frequency electrical noise on the output side of the fan controller, measures must be taken to ensure that wires and cabling are routed
in a manner consistent with recommendations made in this section. Big Ass Fans controllers rely on “motor feedback” through the
cabling to sense motor speed, slip, etc.
CAUTION: The presence of foreign signals on a drive’s output wiring greatly reduces the controller’s ability to control current
and speed regulation of the fan. Any wiring practice that would allow this kind of “cross-talk” must be avoided. Failure to do
so may result in nuisance tripping, and/or premature equipment failure. Sources of foreign signals that could induce such
signals include another VFD’s output circuit, long “across-the-line” motor circuits, and lighting circuits.
Controller AC Supply
Most conventional methods of power distribution and branch circuit installation apply to all models of fan controllers. Installation must
comply with specifications regarding wire types, conductor sizes, branch circuit protection, and disconnecting devices. Failure to do so
may result in personal injury and/or equipment damage. Refer to “Power Requirements” (p. 28) for specific ampacities.
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AC supply feeds for one fan controller can share the same conduit with AC supply feeds for one or more additional controllers.
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AC supply feeds for a fan controller and output/motor leads for the same fan controller cannot share a conduit.
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AC supply feeds for one fan controller cannot share conduit with output/motor leads from one or more additional controllers/VFDs.
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Any unused conductors that share a conduit with an AC supply feed should be grounded on both ends to prevent risk of electric
shock due to induced voltages.
CAUTION: Recommendations for fan controller output/motor lead routing deem some conventional wiring practices
“unacceptable.” National and/or local code does not differentiate between solid-state and electromechanical systems;
however, due to the nature of the Big Ass Fan system, there are additional requirements that must be met to ensure proper
operation.
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Output/motor leads for a fan controller and AC supply feeds for the same fan controller cannot share a conduit.
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Output/motor leads for one fan controller cannot share conduit with AC supply feeds or output/motor leads from one or more
additional fan controllers.
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Any unused conductors that share a conduit with fan controller output/motor leads should be grounded on both ends to prevent risk
of electric shock due to induced voltages.
