Page 3 of 3 FirstFirst 123
Results 21 to 27 of 27

Thread: 2020 Fire Fighter Disco 1 & 2 Family Dwellings 230.85

  1. #21
    Join Date
    Dec 2007
    Location
    NE Nebraska
    Posts
    38,507
    If such requirement ends up happening, I'd like to see exception allowing for shunt trip main and remote switch for fire fighters. If they have to cut a lock before operating the switch, so what, they have the ability to do that.

    As far as spraying water on who knows what... direct stream is what has electrical continuity issues. To fight a fire direct stream is putting a lot of water in a small area, most of the time they are more likely to have wider mist pattern and not a direct stream, unless shooting the stream a long distance, but then allowing it to break up as it falls on it's target.
    I live for today, I'm just a day behind.

  2. #22
    Join Date
    Feb 2003
    Location
    Illinois
    Posts
    23,816
    Quote Originally Posted by kwired View Post
    ...
    As far as spraying water on who knows what... direct stream is what has electrical continuity issues. To fight a fire direct stream is putting a lot of water in a small area, most of the time they are more likely to have wider mist pattern and not a direct stream, unless shooting the stream a long distance, but then allowing it to break up as it falls on it's target.
    Testing done by Purdue University for the US Navy a number of years ago, showed that even with seawater and a straight tip nozzle at 100 psi and 125 gmp, the current at the nozzle would be less than 5 mA at ~15' from energized 440 volt equipment. If the nozzle was set to a 30° fog pattern, the current was less than 5 mA at the nozzle ~2' from the energized equipment.
    The more serious water hazard for fire fighters is standing or flowing water in the floor or ground that is in contact with a power source.
    Don, Illinois
    (All code citations are 2017 unless otherwise noted)

  3. #23
    Join Date
    May 2009
    Location
    Usa
    Posts
    1,617
    Quote Originally Posted by shortcircuit2 View Post
    New proposed section 230.85 requires a Emergency Disconnect for service conductors of 1 & 2 family dwellings located readily accessible outside the dwelling.

    Know as the "Fire Fighter Disconnected"

    Here is the language...

    230.85 Emergency Disconnects(s)
    For one- and two-family dwelling units, all service conductors shall terminate in disconnecting means having a short-circuit rating equal to or greater than the available fault current, installed in a readily accessible outdoor location. If more than one disconnect is provided, they shall be grouped. Each disconnect shall be one of the following:

    (1) Service disconnect(s) marked as follows: EMERGENCY DISCONNECT, SERVICE DISCONNECT

    (2) Meter disconnect(s) installed per 230.83(#) and marked as follows: EMERGENCY DISCONNECT, METER DISCONNECT, NOT SERVICE EQUIPMENT

    (3) Other than listed disconnect switch(es) or circuit breaker(s) on the supply side of each service disconnect that are suitable for use as service equipment and marked : EMERGENCY DISCONNECT, NOT SERVICE EQUIPMENT

    Markings shall comply with 110.21(B)
    Stupid proposal!

  4. #24
    Join Date
    Mar 2003
    Location
    New England
    Posts
    13,587
    Quote Originally Posted by chris1971 View Post
    Stupid proposal!

  5. #25
    Join Date
    Dec 2007
    Location
    NE Nebraska
    Posts
    38,507
    Quote Originally Posted by don_resqcapt19 View Post
    Testing done by Purdue University for the US Navy a number of years ago, showed that even with seawater and a straight tip nozzle at 100 psi and 125 gmp, the current at the nozzle would be less than 5 mA at ~15' from energized 440 volt equipment. If the nozzle was set to a 30° fog pattern, the current was less than 5 mA at the nozzle ~2' from the energized equipment.
    The more serious water hazard for fire fighters is standing or flowing water in the floor or ground that is in contact with a power source.
    Agree, how often is there something on the floor in a dwelling - I suppose extension cords but no permanent wiring.

    Around here you sometimes see center pivot irrigation sprinkler shooting right at 7200 volt to ground POCO primary lines or at transformer banks, nothing happens as it is not a direct stream.
    I live for today, I'm just a day behind.

  6. #26
    Join Date
    May 2018
    Location
    Jamaica and london
    Posts
    939
    Quote Originally Posted by romex jockey View Post
    Agreed one would want them to 'work' at it Adam, while making it easy for 1st responders is the conundrum

    It's how the knox box came to be....

    ~RJ~
    The Knox Box is interesting but still like the idea that Jamaica is toying with... firefighter switch on outside of building but high enough that a pole on the truck is needed for operating it... Based on the UK rules for one... in fact, the wording and signs on it are straight from the BS 7671 codebook...
    The current wording is to require the utility switch and a switch next to it for solar if installed in the residence... and the two cannot be more than 4 feet apart... any apartments etc with separate meters still must have their firefighter switches grouped so the fire fighter could stand in one area and switch them all off... but the 6 switch rule from the NEC is being dropped from the firefighters idea because of the want for all the apartments and solar to be grouped in one area only.. no second areas to go to unless the building is over so many feet... or has more than one utility supply to it...

    Truly, some parts of this make sense to me and other parts of what the proposed changes for the Electrical Code in Jamaica make no sense... they were saying they want to adopt the NEC and now saying it would cause too much confusion to adopt it..I think the country just wants to stay in the 80s..lol
    Student of electrical codes. Please Take others advice first.

  7. #27
    Join Date
    Apr 2009
    Location
    Williamsburg, VA
    Posts
    5,722
    Quote Originally Posted by chris1971 View Post
    Stupid proposal!
    I agree for several reasons. Main one being that 99.999% of fires will not be in a brand new home, and if there is a roaring fire, the disconnect is either going to be overlooked, on fire itself, or attached to a structure that is... on fire... Radiated heat would probably preclude you from getting within 20 feet of thing.

    Plus, even if the disco is there, noticed, and successfully operated, you still have power attached to the house up at that point.

    Short wish list of changes Id like to see would be repealing 210.12 in its entirety, changing the language 200.6 to remark existing and smaller than 4 gauge wire as neutrals, and deleting the requirement to bond coax and telephone to the GES. And leave kitchen island receptacle replacement alone for at least every other code cycle... The rate at which those sections change is ridiculous.
    Electricians do it until it Hertz!

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •