G'day again Dave, Sally & Listers, Good electrician's are hard to get in this country, they're all so busy. But, after a dozen or more phone calls, I finally found a Sparky with a little downtime and he called in at home this morning. He took a quick glance at my switchboard, then a quick peek at my machinery motors and the location where I want the power points and did aquick bit of measurement. His analysis was, "no worries mate, it's a piece of cake!"
It's amazing what comfort the knowledge & experience of a qualified tradesman can provide. His expert eye immediately saw what my ignorant brailling finger had failed to feel. The stippled plastic on the right hand side of my switchboard wasn't a nice design feature, but were two pull-out plastic tabs covering 2 extra spare unused trip switch slots. So, he'll just run 2 6mm cables from the board through the roof and install 2 20+Amp GPO's on the wall close to where I plan to put the Saw and extractor. Thanks Dave for all your help and assistance. The information and ideas you gave, really helped my understanding and explanations to the Sparky of what was required. Cheers, John M Melbourne Australia. PS: In the deepest depths of a Melbourne winter, it rarely gets below 7ºC (44.6ºF) so the likelihood of needing to run my 1500W fan heater often or long is fairly limited. PPS: Australian Standard wiring insulation colours for 3 pin 240V AC are now: Active brown (old red), Neutral blue (old black) and Earth yellow/green (old green). JDM From: dave and sally To: [email protected] Sent: Saturday, September 15, 2007 10:54 PM 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.
