This discussion has been locked.
You can no longer post new replies to this discussion. If you have a question you can start a new discussion

Splitting up a 3 phase area???

Hi everyone,


There are some 21 'open' areas and each 'area' doesn't have a door... each 'area', (about 10ft x 10ft x 20), has to have 4 DSO and a cooker supply / outlet. 


The problem is, as there are so many 'open' areas, (without any doors'), the 3 phase has to be 'balanced', (as we know), and each phase would be broken into about 7 areas, ie; 1 phase for 7 'areas / 'units'. That's simple enough BUT, as there aren't any doors' to these 'areas' / units I'm concerned about someone running, (unlikely but possible), a lead from one 'unit' to another thereby one 'area' would then have 415v in it. 


How could you protect this from happening / alternative wiring? There isn't a bus-bar anywhere and really all of the 21 'units' couldn't be put on the same phase. I don't know what the incoming fuse rating is yet. Has anyone done something similar??


I haven't worked out the amount of amps, per unit, yet but, with some 21 cooker outlets and some 80 odd DSO's it just wouldn't be possible to all go on one phase.


Any ideas welcomed!!


Cheers, Tom

Parents
  • mapj1:

    Why would you worry at all - there is no problem having adjacent equipment on different phases. If you had bare terminals exposed with more than one phase it would be dangerous, but then it would be almost equally dangerous with one phase and neutral exposed. All modern cables plugs and appliances are designed to be quite happy with a lot more than 400V between the case and the live bits inside.

    Three phases do not need to be kept apart - they never did, and now they do not even need to be labelled when they get close together, since the reg requiring that  was deleted in the 1980s, about the same time the idea of cable routing and 'safe' zones first came in.


    Id be quite happy with phase " zones" that overlapped, if it worries you then add a little map at the board so folk know which breaker kills what items.

    Are you having 3 single phase boards or one 3 phase board with single way RCBOs in ?


    Hello Mapj1


    It was something from the past... about mixing 2 phases etc. It's not been worked out yet, whether there's one 3 phase board of separate one's... it's in the rip out stage and then when the units are in place it'll be decided.


    THANKS for your reply, always great to read!!!


    regards... Tom


Reply
  • mapj1:

    Why would you worry at all - there is no problem having adjacent equipment on different phases. If you had bare terminals exposed with more than one phase it would be dangerous, but then it would be almost equally dangerous with one phase and neutral exposed. All modern cables plugs and appliances are designed to be quite happy with a lot more than 400V between the case and the live bits inside.

    Three phases do not need to be kept apart - they never did, and now they do not even need to be labelled when they get close together, since the reg requiring that  was deleted in the 1980s, about the same time the idea of cable routing and 'safe' zones first came in.


    Id be quite happy with phase " zones" that overlapped, if it worries you then add a little map at the board so folk know which breaker kills what items.

    Are you having 3 single phase boards or one 3 phase board with single way RCBOs in ?


    Hello Mapj1


    It was something from the past... about mixing 2 phases etc. It's not been worked out yet, whether there's one 3 phase board of separate one's... it's in the rip out stage and then when the units are in place it'll be decided.


    THANKS for your reply, always great to read!!!


    regards... Tom


Children
No Data