BIG ASS FANS Pivot 180, Installation Manual

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PIVOT™ 180
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PIVOT™ 180
Grounding
CAUTION: The VFD generates high frequency signals on the output side of the fan system. Special grounding
requirements must be followed to ensure proper operation of the fan.
The nature of Variable Frequency Drive systems must be considered prior to and during the installation of Big Ass Fans. Due to high
frequency content on the output side of the fan controller, measures must be taken to ensure that all grounding connections conform to
the recommendations made in this section.
The fan controller’s safety ground (PE) must be connected to system ground. Ground impedance must conform to the
requirements of national and local industrial safety regulations and/or electrical codes. The integrity of all ground connections should be
periodically checked. All ground leads for downstream conduit boxes must be kept separate from the motor ground and terminated on
the fan controller’s PE terminal.
Motor ground
The motor ground must be connected to a ground terminal on the VFD to aid in keeping high frequency electrical noise off of the
building’s ground grid.
Shielded motor cable terminations
Either of the safety ground terminals on the drive provides a grounding point for the motor cable shield. The motor cable shield
connected to one of the drive terminals must also be connected to the motor frame. If no drain lead is present, the cable must be
stripped back so that the braid can be twisted and soldered to a pigtail for proper termination.
Electrical Installation (cont.)
Conduit and piping
AC supply feed guidelines
Due to the nature of the VFD, some non-standard conduit and piping guidelines must be followed to ensure proper fan operation and to
keep the installation within code.
• Big Ass Fan controllers require motor feedback information to detect motor speed and operation and will adjust power accordingly.
The presences of foreign signals on the line could affect this feedback. Avoid wiring schemes that could allow this crosstalk.
• AC supply feeds for one fan controller MAY share the same conduit with AC supply feeds for one or more controllers.
• AC supply feeds for a fan controller and output/motor leads for the same fan controller CANNOT share a conduit.
• AC supply feeds for one fan controller CANNOT share conduit with output/motor leads from one or more additional controllers.
• All unused conductors that share a conduit with the AC supply feeds must be grounded on both ends.
Controller output/motor input guidelines
• MC cable (stranded or solid core) CANNOT be used for fan output/motor input leads.
• Output/motor leads MAY NOT share the same conduit or pipe with any other wiring. This could cause electrical interference or
“crosstalk.”
• Controller output/motor input leads CANNOT share a conduit with any other controller’s output/motor leads.
• Controller output/motor input leads CANNOT share a conduit with the same controller’s AC supply feed.
• Controller output/motor input leads CANNOT share a conduit with any other controller’s AC supply feed.
Diagrams illustrating approved installation techniques are provided on the following pages.