Staircase Pressurization Fan Motor Overload
- Thread starter sccat
- Start date
- Status
- Location
- Illinois
- Occupation
- retired electrician
in general, motors require overload protection. There are some specific motors, fire pump motors, for example that are not permitted to have overload protection. I don't know of anything that would permit you to eliminate the overload protection for your application.
Is Staircase Pressurization Fan one of those ?specific motors? that are not permitted to have overload protection?
And what about "smoke extraction fan"?
- Location
- Illinois
- Occupation
- retired electrician
Not that I know of.
http://www.flaktwoods.com.sg/d065342c-0f7f-442a-9a50-9d38dadb35e7
On page 17,It says " If fitted, overheat protectors in motor windings and any other motor protection device, must be by-passed in emergency."
On page 18,There is no Overload Relay in the emergency circuit.
Is that correct?
On page 17,It says " If fitted, overheat protectors in motor windings and any other motor protection device, must be by-passed in emergency."
On page 18,There is no Overload Relay in the emergency circuit.
Is that correct?
http://www.nicotra-gebhardt.com/upload/download-center/catalogue/TD_SEF_SLCS_DE.pdf
Page 209:
All installed motor protection units and/or over current or temperature limiting switches have to be by-passed in the event of smoke extraction.
In this case the fan has to connected directly to the mains without any motor protection.
Be careful to not loose the certificate by switching to an unauthorised operational mode.
Page 209:
All installed motor protection units and/or over current or temperature limiting switches have to be by-passed in the event of smoke extraction.
In this case the fan has to connected directly to the mains without any motor protection.
Be careful to not loose the certificate by switching to an unauthorised operational mode.
- Location
- Illinois
- Occupation
- retired electrician
I still am not aware of any section of the NEC that would permit the bypass of the overload device. Maybe there is something in the high rise fire codes.
J
janagyjr
Guest
What about the section that pertains to installing equipment as listed by manufacturer?
- Location
- Illinois
- Occupation
- retired electrician
Show me a listing document (the actual standard or White Book information) that says that and I will agree. I won't agree that the manufacturers instructions can over ride a code rule.
J
janagyjr
Guest
Article 110.3(B) (2011, as thats what I have handy) states:
"Listed or labeled equipment shall be installed and used in accordance with any instructions included in the listing or labeling."
"Listed or labeled equipment shall be installed and used in accordance with any instructions included in the listing or labeling."
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- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
Don's point is that the manufacturers instructions may not be part of the listing and labeling.
J
janagyjr
Guest
Might not be in the listing, but doesn't an instruction manual, provided by the manufacturer, count as the labeling? If not, than I've been sorely mislead by the authors of my text books.
Twoskinsoneman
Senior Member
- Location
- West Virginia, USA NEC: 2020
- Occupation
- Facility Senior Electrician
what you may find is that some folks will change there view on that based on what supports their argument. If the device has a little instruction book that spells out instructions for installation is that a label?
- Location
- Illinois
- Occupation
- retired electrician
My point is that the manufacturer's instructions can never require you to violate a code rule. Even if the instructions are a part of the listing and labeling...which in my opinion very few are, they can not require you to violate a code rule. A listing does not over ride the NEC.
J
janagyjr
Guest
I don't see how following the code (110.3(B) in this case) causes you to violate any rule.
I have seen 125 volt plug connected commercial kitchen equipment which has instructions that state not to use on GFCI circuits, this just means this particular manufacturers equipment can not be used in commercial kitchens that are wired under current NEC rules. So with that said, if a piece of equipment has instructions that instruct us to install in a non-compliant way the equipment has to be sold to a third world country.
Listing and labeling with instructions does not mean equipment can be legally used.
Roger
J
janagyjr
Guest
Okay, because the thread is way OT now because of me (my bad) and because I'm now confused, I'm taking an example directly from my text book (Electrical Wiring Residential, 16th Edition, Ray C. Mullin (author)):
"410.136(B) states that fluorescent luminaires that are surface mounted on this material must be spaced at least 1?" from the fiberboard surface unless the fixture is marked "Suitable for Surface Mounting on Low-Density Cellulose Fiberboard.""
The "unless" fully conforms to 110.3(B). if the manufacturer's instructions for the fan thing that was being discussed is labeled (or has instructions to allow) for use with the overloads bypassed (in certain situations), how is any of the code being violated? I agree, motors in general are required to have overload protection but in this case - if these are the instructions being provided - does it not go to say that it has been tested by the UL in this fashion? Otherwise the manufacturer would be violating the listing and the law by providing said instructions.
Yet by your interpretation that would make the installation non-compliant.
"410.136(B) states that fluorescent luminaires that are surface mounted on this material must be spaced at least 1?" from the fiberboard surface unless the fixture is marked "Suitable for Surface Mounting on Low-Density Cellulose Fiberboard.""
The "unless" fully conforms to 110.3(B). if the manufacturer's instructions for the fan thing that was being discussed is labeled (or has instructions to allow) for use with the overloads bypassed (in certain situations), how is any of the code being violated? I agree, motors in general are required to have overload protection but in this case - if these are the instructions being provided - does it not go to say that it has been tested by the UL in this fashion? Otherwise the manufacturer would be violating the listing and the law by providing said instructions.
Yet by your interpretation that would make the installation non-compliant.
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No, you are not comparing apples to apples, 410.136(B) specifically allows the installation per the manufacturers listing and labeling / instructions and has wording for this.
Can you provide another article section which will specifically allow the topic at hand?
Roger
J
janagyjr
Guest
At this point, that's pretty much what I'm asking.
elohr46
Senior Member
- Location
- square one
Those fans are controlled by the Fire Alarm system, you may find the answer you're looking for in NFPA 72. I have wired these before and don't recall them not having overloads in the control circuit. It's possible the FA installer put a relay in to bypass the OL circuit, I don't remember to tell you the truth. Oft times there are key switches located in the Fire Command room where the Fire Marshall can operate those fans at his discretion.
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