Big "donkey's buttl" Fan, 10 feet wide

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Buck Parrish

Buck Parrish

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Location
NC & IN
Out of respect for the owner of this site I have not used the real name of the fan. Even the company has a controversial name.
Has any body installed one of these ? http://www.bigassfans.com/ I am roughing in an area for the fan and switch. It has 21 speeds and is suppose to go in reverse from the switch. It is 10 feet in circumference.
I'm told they are becoming more popular for high locations.
 
iwire

iwire

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Staff member
Location
Massachusetts
Buck Parrish said:
Out of respect for the owner of this site I have not used the real name of the fan. Even the company has a controversial name.
Has any body installed one of these ? http://www.bigassfans.com/ I am roughing in an area for the fan and switch. It has 21 speeds and is suppose to go in reverse from the switch. It is 10 feet in circumference.
I'm told they are becoming more popular for high locations.
Click to expand...

We have done some, they had large control boxes at ground level.
 
iwire

iwire

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Staff member
Location
Massachusetts
Buck Parrish said:
What type of box did you set for it?
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None, it was piped into.

Found this on the web
ba-fans.jpg
 
K

Kdog76

Senior Member
Location
The Dairyland State
I wired in two of them. The customer service at the company really helped us a lot. They even helped us program the VFD to eliminate a humming problem - I've never touched a PLC pefore that and they talked me right through it. I believe we used a SJO cord from the fan to J-Box in the ceiling. I know we hard piped it from the control box to the j-box in the ceiling and they wanted each fan wiring in separate conduits from each control box to each fan and the conduits had to be spaced out a distance from each other. My favorite part was calling the 1-800 number and hearing the operater state the name of the company. Still brings a smile to my face. Oh, the hardest part was guying the fan's downrod back up to the ceiling. It took 2 guys the better of the day for two fans. Good luck.
 
Dennis Alwon

Dennis Alwon

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Location
Chapel Hill, NC
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Retired Electrical Contractor
Buck they have one at the University surplus building off Estes Drive in Chapel Hill. I am sure you can go there and check it out.
 
gadfly56

gadfly56

Senior Member
Location
New Jersey
Occupation
Professional Engineer, Fire & Life Safety
Fire Alarm Considerations

Fire Alarm Considerations

One of the engineer/salesmen in our office regularly attends the local Society of Fire Protection Engineers meetings. There was a report presented at one of the meetings describing the challenges these fans can present from a fire perspective. The use of these fans in sprinklered spaces is potentially problematic. In the event of a fire in the protected space, the area of coverage and volume of air moved is such that the heat plume can be horizontally displaced. This may cause activation of the sprinklers not actually over the fire! It is important that when a fire is detected by an automatic fire detection system that the fans be shut down, especially if they utilize detection methods less likely to be affected by the fan operation such as beam detectors, flame detectors, or video cameras which often respond more quickly than sprinklers.
 
J

John120/240

Senior Member
Location
Olathe, Kansas
gadfly56 said:
One of the engineer/salesmen in our office regularly attends the local Society of Fire Protection Engineers meetings. There was a report presented at one of the meetings describing the challenges these fans can present from a fire perspective. The use of these fans in sprinklered spaces is potentially problematic. In the event of a fire in the protected space, the area of coverage and volume of air moved is such that the heat plume can be horizontally displaced. This may cause activation of the sprinklers not actually over the fire! It is important that when a fire is detected by an automatic fire detection system that the fans be shut down, especially if they utilize detection methods less likely to be affected by the fan operation such as beam detectors, flame detectors, or video cameras which often respond more quickly than sprinklers.
Click to expand...

In the fall of 2009 we installed 5 BAF in a one million sq ft warehouse. We had to install smoke

detectors on the fan. We used 3/4 " PVC pipe, orange in color, piped to the nearest column

where the somke detector contro0l box was. Only two fans had the detectors, one fan

controlled two other fans, one fan controlled one fan. For installation of the fans two men

4 hours per fan is about right. After you figure out the first one, thet go smoother.
 
C

Christoff84

Member
Location
Ontario, Canada
We installed 3 of these in our plant and they work great. Just a stand alone VFD and line reactor in the box sized based on the manufacturer of the VFDs specs. I think they are roughly 14 x 12 x 9 boxes we used. Just hard piped up to the ceiling then out to flex with T90 wire.

We were told recently by the insurance company/fire department that they need to have a kill switch if the sprinkler alarms go off as they will just stir up everything and fan the fire.
 
kwired

kwired

Electron manager
Location
NE Nebraska
Why is the problem with fire detection or "fanning the fire" any more of a problem than any other means to move the same amount of air? If you are not going to use one of these large fans yet want to move similar amount of air you will just put more but smaller fans or some other system that will effectively do the same thing
 
gadfly56

gadfly56

Senior Member
Location
New Jersey
Occupation
Professional Engineer, Fire & Life Safety
kwired said:
Why is the problem with fire detection or "fanning the fire" any more of a problem than any other means to move the same amount of air? If you are not going to use one of these large fans yet want to move similar amount of air you will just put more but smaller fans or some other system that will effectively do the same thing
Click to expand...

Multiple fans produce interferences which don't lead to monolithic columns of downcoming air. Our engineer, who is very experienced in sprinkler design, was quite impressed with the video. I can't comment of my own knowledge. We tie into the emergency shutdown contacts in the controller.
 
kwired

kwired

Electron manager
Location
NE Nebraska
gadfly56 said:
Multiple fans produce interferences which don't lead to monolithic columns of downcoming air. Our engineer, who is very experienced in sprinkler design, was quite impressed with the video. I can't comment of my own knowledge. We tie into the emergency shutdown contacts in the controller.
Click to expand...

What about exhaust fans or even natural convection ventilation outlets that will let smoke and heat out and possibly effect the response time of fire detection? A good design would need to take this into consideration.
 
gadfly56

gadfly56

Senior Member
Location
New Jersey
Occupation
Professional Engineer, Fire & Life Safety
kwired said:
What about exhaust fans or even natural convection ventilation outlets that will let smoke and heat out and possibly effect the response time of fire detection? A good design would need to take this into consideration.
Click to expand...

Possibly, but the effects of unducted exhaust fans, for example will be minimal. If you've ever done work around a kitchen range hood you can understand that immediately. Right in front of the exhaust duct you can easily loose your hat. A few inches away, there's a stiff breeze. Stand on the floor, but still under the hood, and there's a general sense of air movement around you. Step out from under the hood and a few feet away, and you generally can't feel any difference in the local air velocity field between "fan on" and "fan off". The bulk velocity of the air in the enclosed space is affected, but at a very low level.
 
iwire

iwire

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Staff member
Location
Massachusetts
kwired

kwired

Electron manager
Location
NE Nebraska
iwire said:
I guess you have to go straiten out the NFPA and show them how foolish they are.:roll:

In case you missed Pete posting this http://www.nfpa.org/assets/files//P...ffects_of_Air_Movement_Created_by_HVLS_Fa.pdf
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That appears to be mostly about how the fan effects a fire as well as the effect on a sprinkler system. What about any effects on fire detection? That is what my comment was about in my last post.

Detection probably still works with increased air movement but may be delayed because heat and smoke will not concentrate as much as with still air, which means more burning time before an alarm occurs.

I don't know what really happens but this seems logical it could be a potential problem.
 
G

ggunn

PE (Electrical), NABCEP certified
Location
Austin, TX, USA
Occupation
Consulting Electrical Engineer - Photovoltaic Systems
I am no expert on such things, but I have wondered about those ducts that firemen use to remove smoke from a building. If you remove air/smoke from a building at one point, that means you are pulling fresh air into it at another location, and doesn't that encourage combustion?
 
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