37 - Elevator Recall - Correcting a mistake from the last video - Introduction to Fire Alarms
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- Опубликовано: 8 дек 2019
- In this video I correct a mistake I made in the last video. I give an alternate building scenario which explains why I feel my explanation of zoning the relays in the last video wasn't done optimally.
A real man knows when he was wrong
Well done.
I like your speed. I get it. Keep it up!
Pit detectors would only be required if the elevator is hydraulic and the sprinkler(s) is/are above 2'. But smoke detector not allowed because there are no weatherproof rated smoke detectors on the market, as all devices/wiring in the pit are required to be weatherproof.
There are smokes in the pit all the time. The pits have sump pumps, so it's not a wet location. I think with new elevator codes they don't require the smokes very often, but in the past it's been very common to have them in there. I've never seen a single weather resistant heat detector in an elevator pit. They're usually addressable heats, which are also not waterproof.
@@JoeKlochanBelieve me, my experience as far as what I've seen installed in hoistways is the same as yours. On a hydraulic elev all devices and wiring below 4' of the pit floor is required to be rated NEMA4 and for wet locations respectively. Heat detectors can be found that are NEMA4, but are required to be installed within 12" of the ceiling, same as smoke detectors (which none available are NEMA4 rated). So, no smokes or heats allowed in the pit. A heat installed at TOS is allowed to perform both the recall and shunt trip functions the pit heat/smoke would perform...or a waterflow switch with no retard after that sprinkler "floor control valve" for the hoistway.
But, wait til next ANSI elev/NEC/IFC/72/101...it'll change again hehehe
To be clear Joe, I'm not critizing your RUclips video(s). I wish you created more often.
My intent is simply to show the code confusion as far elev control from fire alarm hoistway devices over the years.
For instance, it was "standard" procedure to have TOS smoke detectors in all elevators hoistways in most mid/high rise buildings...at least in Houston, TX. These elevators were of course not hydraulic and most tall buildings in the 70's, 80's even into the 90's were not sprinklered. Now of course, there SHALL be no smoke detectors in a hoistway unless sprinklered and/or hoistway smoke control, and if required to be installed have to be safely accessible. I think we can agree this whole elevator Thang has been and continues to be a cluster F.
Make more videos !