Electrical supply for current-hungry appliances...
Discussion
inabox said:
Sorry, not to take this off-topic, but what have I posted thats incorrect?
The earlier post about this being Alucidnation's typical response to the notion that anyone other than him can understand electricity is fairly accurate, but there's something here that you need to get your head around a bit more clearly:inabox said:
It's because people turn off the isolator, open it up and take out the appliance, all the while there's a live feed with 32a.
Two main things - amps don't sit there waiting to bite - voltage does; and a LOT less than 32A can kill you - MCBs (like fuses) are there to protect equipment, not people.RoverP6B said:
Fair enough. Any idea of installation costs, and the practicalities of getting it run in? Better to be armed with knowledge beforehand!
How long is a piece of string... you'll need overhead or underground lines run from the nearest 3 phase supply. You may or may not need a transformer at one or both ends of this new run. Chances are it really won't be worth it.RoverP6B said:
Fair enough. Any idea of installation costs, and the practicalities of getting it run in? Better to be armed with knowledge beforehand!
Depends on how far away the nearest 3PH is, a farmer customer of mine paid around £17K for 1/2 mile of over head lines installed over his field's.Standing charge will be higher for a start with running costs.
RoverP6B said:
Fair enough. Any idea of installation costs, and the practicalities of getting it run in? Better to be armed with knowledge beforehand!
It would probably be in the thousands rather than hundreds, however, it very much depends how the supply is run externally.You could contact your local supplier and they will normally come out and do a survey, but some are now doing 'desktop quoting'.
B.S. beat me to it.
Jambo85 said:
inabox said:
Sorry, not to take this off-topic, but what have I posted thats incorrect?
The earlier post about this being Alucidnation's typical response to the notion that anyone other than him can understand electricity is fairly accurate, but there's something here that you need to get your head around a bit more clearly:inabox said:
It's because people turn off the isolator, open it up and take out the appliance, all the while there's a live feed with 32a.
Two main things - amps don't sit there waiting to bite - voltage does; and a LOT less than 32A can kill you - MCBs (like fuses) are there to protect equipment, not people.Are you saying it the current or the voltage that kills, your post is confusing to understand.
inabox said:
Alucidnation said:
As you clearly don't know what you are talking about, you should stop giving out advice..
Sorry, not to take this off-topic, but what have I posted thats incorrect? I only ask because this is how my boss does it and how I've been taught at college, I've only got 6 months left of a 4 year course and would rather not go out and do the wrong thing. (other than it should be 45a isolator and outlet, blame late nights, sorry).Edited by Alucidnation on Thursday 9th November 22:22
Cheers
Edited by inabox on Friday 10th November 07:22
that's quite scary.
you should be able to work out the maximum length of cable and its size, for a given maximum current demand and the voltage drop you'll get as a result, and if that complies with the wiring regs on max permissible voltage drop. you should also know that where that cable runs, and how warm it is, and how its fixed affects what size it is!
out of interest, what level of college course are you doing? my advise is get a good guide to the wiring regs, and how to size cables etc.
Yabu said:
Are you saying it the current or the voltage that kills, your post is confusing to understand.
I'm not saying it is one or the other - for an effective electrocution you definitely need both. Rather I felt that inabox wrote something that showed a lack of understanding about what current is, and what makes a supply hazardous, and since he is working in this area I tried to help. To spell it out, an un-isolated single phase supply rated for, say, 6A is not any safer than one rated for 32A - with regards to electrocution.
It's generally accepted that even very low currents will kill you (particularly on ac) as long as the voltage is enough to overcome your body resistance where contact is made.
Some people will survive what will kill others instantly. You'll remember the first time you get a proper shock and walk away for the rest of your life:-)
Some people will survive what will kill others instantly. You'll remember the first time you get a proper shock and walk away for the rest of your life:-)
200Plus Club said:
I'd be hoping that with 6 months left of a 4 year (electrical?) apprenticeship you knew more than "its how my boss does it?
that's quite scary.
you should be able to work out the maximum length of cable and its size, for a given maximum current demand and the voltage drop you'll get as a result, and if that complies with the wiring regs on max permissible voltage drop. you should also know that where that cable runs, and how warm it is, and how its fixed affects what size it is!
out of interest, what level of college course are you doing? my advise is get a good guide to the wiring regs, and how to size cables etc.
This is how it panned out :-that's quite scary.
you should be able to work out the maximum length of cable and its size, for a given maximum current demand and the voltage drop you'll get as a result, and if that complies with the wiring regs on max permissible voltage drop. you should also know that where that cable runs, and how warm it is, and how its fixed affects what size it is!
out of interest, what level of college course are you doing? my advise is get a good guide to the wiring regs, and how to size cables etc.
Alucidnation said:
32A MCB, 6mm, into an isolator and wire the f
ker straight in.
No need for commando sockets of any type.
ker straight in.No need for commando sockets of any type.
inabox said:
Please don't put it straight into an isolator. To the best of my knowledge it's meant to go:
32a MCB >> 4 or 6mm² cable >> 40A isolator >> 4 or 6mm² cable >> 40A outlet >> 4 or 6mm² cable >> appliance
It's because people turn off the isolator, open it up and take out the appliance, all the while there's a live feed with 32a.
Unable to take a bit of constructive criticism :-32a MCB >> 4 or 6mm² cable >> 40A isolator >> 4 or 6mm² cable >> 40A outlet >> 4 or 6mm² cable >> appliance
It's because people turn off the isolator, open it up and take out the appliance, all the while there's a live feed with 32a.
Alucidnation said:
As you clearly don't know what you are talking about, you should stop giving out advice..
When in fact he was quite correct, its always good practice to wire an outlet plate after the isolator so the appliance has something safe to connect to instead of just a piece of 6mm hanging out the wall. It was nothing to do with sizing cables for volt drop or anything he just mentioned a correct way of doing things.Why are domestic properties prohibited from having 3ph but converted houses in commercial use can have it, then?
Naturally, I would not attempt any part of the installation myself, a qualified electrician would do the job, if it were required. Just doing my homework before embarking on a project.
Naturally, I would not attempt any part of the installation myself, a qualified electrician would do the job, if it were required. Just doing my homework before embarking on a project.
Gassing Station | Homes, Gardens and DIY | Top of Page | What's New | My Stuff