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
Grounding
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.
CAUTION: The following information is merely a guide for proper installation. The Big Ass Fans Company cannot assume
responsibility for the compliance or the non-compliance to any code, national, local, or otherwise for the proper installation of
these fan controllers, fans, or associated equipment. A hazard of personal injury and/or equipment damage exists if codes are
ignored during installation.
The fan controller’s Safety Ground
(PE) must be connected to system ground as shown in the “Standard Grounding” diagrams
on pp. 36-37. 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 as shown in the “Standard Grounding”
diagrams on pp. 36-37.
Motor Ground
The motor ground must be connected to a ground terminal on the VFD as shown in the “Standard Grounding” diagrams on pp. 36-37.
This aids 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 as shown in the “Shielded Motor Cable Grounding”
diagrams on pp. 38-39. 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.
Multi-Fan Grounding Requirements
The grounding requirements for multi-fan controllers are illustrated in the “Multi-Fan Grounding” diagrams on p. 40. It is important to
follow the wiring and conduit requirements previously outlined to ensure proper operation.
RFI/EMI Filter Grounding
Using RFI/EMI filters on BAF fan controllers may result in relatively high ground leakage currents. Therefore, the filter must only be
used in installations with grounded AC supply systems and be permanently installed and solidly grounded (bonded) to the building
power distribution ground. Grounding must not rely on flexible cables and should not include any form of plug or socket that would
permit inadvertent disconnection. Some local codes may require redundant ground connections. The integrity of all connections should
be periodically checked. Refer to the “RFI/EMI Grounding” diagrams on pp. 41-42.
CE Compliant Installations
(pp. 71-75)