Ring mains rock! They allow lighter gauge wire and they use a cartridge fuse mounted in the plug where, in my opinion it should be. If an appliance or it's cord become faulty that is where the circuit fails unless of course the entire circuit has too many things loading it.
Dale Leavens, Cochrane Ontario Canada [EMAIL PROTECTED] Skype DaleLeavens Come and meet Aurora, Nakita and Nanook at our polar bear habitat. ----- Original Message ----- From: Max Robinson To: blindhandyman@yahoogroups.com Sent: Saturday, September 15, 2007 1:31 PM Subject: Re: [BlindHandyMan] Correction: 50Hz, 240Volt, 15Amp power supply for 3HP Table Saw+1½HP dust extractor. What I find most fascinating about this thread is the difference in terminology between the U S and the U K. Also there seems to be some difference in technique. For example the Ring circuit. In the U S we would just run larger diameter wire. Also there is the matter of color coding, I guess you spell it coulor. You use black for the neutral while in the U S we use black for the hot and white for the neutral. That seems totally illogical to someone like me who has worked in electronics for all my life. I'm glad to know that good sense applies somewhere in the world. Regards. Max. K 4 O D S. Email: [EMAIL PROTECTED] Transistor site http://www.funwithtransistors.net Vacuum tube site: http://www.funwithtubes.net Music site: http://www.maxsmusicplace.com To subscribe to the fun with tubes group send an email to, [EMAIL PROTECTED] ----- Original Message ----- From: "dave and sally" <[EMAIL PROTECTED]> To: <blindhandyman@yahoogroups.com> Sent: Saturday, September 15, 2007 7:54 AM Subject: Re: [BlindHandyMan] Correction: 50Hz, 240Volt, 15Amp power supply for 3HP Table Saw+1½HP dust extractor. hi john, ok then it sounds like you have a little bit of a problem should you have been doing this yourself. however a qualified spark should have no problems in sorting this out. it seems he has a couple of options open to him. lets assume that because you already have the lights and sockets in your garage sorted and they dont need to be changed. if he is only going to run a 20 amp circuit for your saw, he could tackle this in one of 2 ways. the first one would be to find the 15 amp fuses for the circuits that you use the least. possibly your bedrooms and living room area. he could piggy back these into one, because the diversity factor should keep you ok, as it is unlikely you will be using lots of power in the bedroom and in the living room at the same time. this would leave you a spare slot on your board and you could change the fuse or trip to a 20 amp one. or he could try and find the cables supplying the board and put 2 100 amp isco connectors on them, and bring out an extra set of tails to feed the new board. (isco connectors are single connector blocks designed for terminating cables which are carying high current, usually 60 amps or more). he may know these as something else, but isco is the common name here in the uk. if you are just running in a cable for your saw and extractor, considering the length, and the loading, you may get away with a 2.5 mm twin and earth cable, as this will cary up to 26 amps, but always keep into consideration future expansion. it may be worth while putting in a heavier cable as the biggest part of the price you are going to pay is for the sparks time. if you were here in the uk, you would even get away with putting in 2 2.5 mm cables in paralell, this would give you more current carying capacity, and you would be allowed to fuse this at 30 amps. another possibility is that he turns your existing garage circuit into what we call here in the uk a ring main. to do this, assumeing your existing garage circuit is wired with 2.5 mm cable or heavier, all he needs to do is create a ring main by running a similar sized cable back to the board and connect it into the existing slot on your board, and providing the new parts can be found, replace the 15 amp breaker with a 30 amp breaker. however this will restrict you for future expansion. as when you are using your saw extractor and 3 kw heater, you will be sitting around maximum load. hope this helps. any more questions just ask. by the way, what size of heater is it you want to use? Dave & Sally. buy and sell your surplus free, join the new mailing group by sending a blank email to. [EMAIL PROTECTED] or find more details here. http://www.secretsthatwekeep.com/thebargainstore/invite.htm ----- Original Message ----- From: John M To: blindhandyman@yahoogroups.com Sent: Saturday, September 15, 2007 11:13 AM Subject: [BlindHandyMan] Correction: 50Hz, 240Volt, 15Amp power supply for 3HP Table Saw+1½HP dust extractor. G'day again Dave & Sally, Wow dave, what can I say for the value of the expertise you've given me, and perhaps others, except thanks and thanks again. I now have much more idea and understanding of what I need to say to the Sparky who is calling in home next Monday. And, i'll now have a much better understanding of what he might put to me as answers and solutions to the issues I have. I know it makes no real difference to the questions/challenge I posed, but in error I said that Australian power supply is 60Hz. It isn't, it's the same as the UK, namely 50Hz. Last post, I failed to say that my existing workshop/garage is already fitted with lighting, albeit presently only two 40W incandescent bulbs and also 5 15Amp standard household power outlets. I've tested it, and the garage lighting is on the house 10Amps lighting circuit, and the 5 power outlets are running off one of my 6 household 15Amp power circuits. That is to say, if i flip off the last (right hand side) trip switch on my switchboard, then all power to the garage is off - though the lights remain on. So, I guess that indicates there's already a proper lighting/power circuit separation. I've worried about such things as the previous owner of my home was a Builder, and so far as building construction regulations go, he broke every one ever written. :) Dave, there's a couple of things I don't quite understand yet. My mains fuse box/switchboard is a plastic box measuring 310mm's by 276mm's that's recessed into the plaster wall near my front door. It has a total of 8 trip switches inside it. The first (left hand side) is a very wide switch which is the main power cut out -it shuts off everything - lighting & power. The second switch is physically set slightly higher than all others, and is the trip switch for all 10Amp household lighting. the remaining 6 trip switches control the 15Amp power outlets in various sections of the house -front bedrooms/bathrooms, hallway, lounge, dining room, Study kitchen laundry and then Garage etc....but there are no spare slots or vacant switches. So then , where will the Sparky pick up a connection to take another heavy duty 30Amp line out to the Garage? Is the connection picked up from somewhere inside the wall, behind my existing switchboard? If so, is this the sub-mains with its own overload cutout switchboard you were referring to? My garage is a good Cricket pitch's length (22 yards) from the existing switchboard. The external electricity metre is recessed into a double brick wall that is a further 10 yards away and there's not a hint of any electricity cable or conduit piping anywhere. I reckon it must be carried inside the wall. Because of paved concrete path and driveways there's no chance of carrying any new cabling underground, it'll all have to go through the roof cavity, but I'm just a single story dwelling, so there should be no real problems there. OK Dave, thanks again, John M Melbourne Australia. From: dave and sally To: blindhandyman@yahoogroups.com Sent: Friday, September 14, 2007 11:29 PM Subject: Re: [BlindHandyMan] 240Volt, 15Amp power supply for 3HP Table Saw+1½HP dust extractor. hi john, you are similar to us here in the uk. the only diffirence is that you are 60 hz and we are 50. but that wont make any diffirence in what you want to do. from my point of view, if it were me i would run in at least a 30 amp radial circuit (sometimes known as a sub main, but you may consider a 45 amp sub main to give you capacity for further development. from this you can then take of a 20 amp dedicated circuit for the saw and dust extractor, and a further 15 amp circuit for your heater, and a further circuit for your lights. not sure what you are allowed to do in australia as regards the size of cables, but what you need to take into consideration is the distance away from the supply line you are going to run your saw. because the further away you are, the more cable you need to use, and the more the voltage drop will be under load. for cost effectiveness, for a short run of cable under 5 metres, it will probably be cheaper and easier for you to run in your sub main with a 6mm twin and earth cable. similar to what you would put in for a small electric cooker or a 8.5 kw electric shower. however, if the run is extrimely long you will need to use a 10mm cable, as this will have less voltage drop, and allow you for future expansion. your saw and extractor will draw maximum load on start up, and going on the figures you gave me this will be around 14 or 15 amps, but you will be right at the limit of your fuze if you put in a 15 amp breaker. so this is why i would put in a 20 amp on this circuit. it all depends on your heater, but if it is a 3 kw heater, you will need a further 15 amps for this. and your 6 lights will need around 5 amps. so adding this up, you have the potential to use around 35 amps when evrything is on. so for safety sake and allowing for future development, your instilation should be capable of taking around 45 amps on maximum load, so you should fuse your isolator switch accordingly. giving a choice i would get your spark to put in a 4 way board close to your saw, fused as follows. a 20 amp for your saw and extractor, a 15 amp circuit for your power outlets and a 10 amp circuit for your lighting. the spare would be for future development such as drills and other power tools. the other thing to take into consideration is how are you going to run your cable. is it overhead, or is it underground. there are specialist underground cables for this job, you can use what we call pyro, this is a special cable with a solid copper outer which is used as the earth conductor, but may not be a good idea if you are putting it anywhere it can get damaged. it also needs specialist crimping tools to make the ends. my choice for underground would be either steel wire armoured, or twin pvc hi tuf. if you are not sure what these are, please ask me for more details. best of luck, and if there is anything you are not sure off, please email me back. Dave & Sally. To listen to the show archives go to link http://acbradio.org/handyman.html or ftp://ftp.acbradio.org/acbradio-archives/handyman/ The Pod Cast address for the Blind Handy Man Show is. http://www.acbradio.org/news/xml/podcast.php?pgm=saturday Visit The Blind Handy Man Files Page To Review Contributions From Various List Members At The Following address: http://www.jaws-users.com/handyman/ Visit the archives page at the following address http://www.mail-archive.com/blindhandyman@yahoogroups.com/ If you would like to join the Blind Computing list, then visit the following address for more information: http://jaws-users.com/mailman/listinfo/blind-computing_jaws-users.com For a complete list of email commands pertaining to the Blind Handy Man list just send a blank message to: [EMAIL PROTECTED] Yahoo! Groups Links [Non-text portions of this message have been removed] To listen to the show archives go to link http://acbradio.org/handyman.html or ftp://ftp.acbradio.org/acbradio-archives/handyman/ The Pod Cast address for the Blind Handy Man Show is. http://www.acbradio.org/news/xml/podcast.php?pgm=saturday Visit The Blind Handy Man Files Page To Review Contributions From Various List Members At The Following address: http://www.jaws-users.com/handyman/ Visit the archives page at the following address http://www.mail-archive.com/blindhandyman@yahoogroups.com/ If you would like to join the Blind Computing list, then visit the following address for more information: http://jaws-users.com/mailman/listinfo/blind-computing_jaws-users.com For a complete list of email commands pertaining to the Blind Handy Man list just send a blank message to: [EMAIL PROTECTED] Yahoo! Groups Links -- No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.5.487 / Virus Database: 269.13.19/1008 - Release Date: 9/14/2007 8:59 AM [Non-text portions of this message have been removed]
