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| Thread ID: 98561 | 2009-03-29 06:03:00 | Electrical Rules | pine-o-cleen (2955) | PC World Chat |
| Post ID | Timestamp | Content | User | ||
| 760435 | 2009-03-29 08:14:00 | When I was a kid we had a bach with a long-drop, and like most of its kind, it got rather whiffy in summer, and it had no light. Being of an electrical bent even then, I procured two old radio transformers, put one in a box with a three pin plug lead, wired the 12.6 vac winding (6.3 a side) to an overhead cable to the long-drop where it went into the 12.6 winding and produced 230 volts on the original primary that I was then using as a secondary. I had a 12 volt car bulb for illumination on the incoming 12.6 volts and a small 230 volt motor with fan on the 230 volt secondary. This was extracting air from below the seat and exhausting it from a pipe above the roof. Negative pressure below the seat ensured that air flow went down, not up, and the time delay between plugging in and getting out there meant it was always odour free, and there was even enough light to read by. Being twice insulated from the mains it was legal, and if you have no great electrical demands to make in your shed you could do similar but with higher rated transformers. The beauty of this system is that you only need two identical transformers with 220-240 volt primaries. The secondary voltages are irrelevant and you just interconnect two suitable high current secondary windings to get the full rated input power and voltage (less transformer and cable losses) at the other end. You can buy any old oddments in a surplus shop with weird or unknown secondaries, the sort that nobody else will touch so they sell cheap, so long as you get two the same. I'm making a low power 230-115 volt stepdown transformer at the moment to run an American instrument using three small surplus 230 volt to 7.6 volt transformers. The input transformer is standard 230v to 7.6 volt that feeds into two 7.6 volt secondaries in series, each receiving 3.8volts. The output primaries (now acting as secondaries) are paralleled, so I get 115 volts out. Cheers Billy 8-{) |
Billy T (70) | ||
| 760436 | 2009-03-29 18:38:00 | I installed one of those cheapo "sun-powered" lights in my garden shed, works beautifully. Now, if I want a power point, it will be a problem. Why not use a long extension lead pine-o-cleen that you install semi-permanently (or is it against the regulations? Oops) sarel |
sarel (2490) | ||
| 760437 | 2009-03-30 00:02:00 | I just realized I'll have to dig across a path. So maybe overhead in conduit. I will have to check the height of the shed. I ran power underground to my garage some years back and it had a concrete path in the way. I dug down to below the path on both sides and drove a pipe underneath and fed the cable through that. Bit of a job but beats digging through a concrete path! The grass grew back and you'd never know anything was disturbed. Underground looks much better than overhead. |
Roscoe (6288) | ||
| 760438 | 2009-03-30 06:55:00 | I ran power underground to my garage some years back and it had a concrete path in the way . I dug down to below the path on both sides and drove a pipe underneath and fed the cable through that . Bit of a job but beats digging through a concrete path! The grass grew back and you'd never know anything was disturbed . Underground looks much better than overhead . Yes, he is right . Dig the trench & make the "Hole Thro" yourself, then ring an Electrician to do the rest . I knoe it will costa few $$$ but you will be happy that it is done legally & hopefully correctly . You will need that Electrical WOF for the insurance Co if you burn the shed down . PJ Ex Electrician . |
Poppa John (284) | ||
| 760439 | 2009-03-30 07:01:00 | When I was a kid we had a bach with a long-drop, and like most of its kind, it got rather whiffy in summer, and it had no light . Being of an electrical bent even then, I procured two old radio transformers, put one in a box with a three pin plug lead, wired the 12 . 6 vac winding (6 . 3 a side) to an overhead cable to the long-drop where it went into the 12 . 6 winding and produced 230 volts on the original primary that I was then using as a secondary . I had a 12 volt car bulb for illumination on the incoming 12 . 6 volts and a small 230 volt motor with fan on the 230 volt secondary . This was extracting air from below the seat and exhausting it from a pipe above the roof . Negative pressure below the seat ensured that air flow went down, not up, and the time delay between plugging in and getting out there meant it was always odour free, and there was even enough light to read by . Being twice insulated from the mains it was legal, and if you have no great electrical demands to make in your shed you could do similar but with higher rated transformers . The beauty of this system is that you only need two identical transformers with 220-240 volt primaries . The secondary voltages are irrelevant and you just interconnect two suitable high current secondary windings to get the full rated input power and voltage (less transformer and cable losses) at the other end . You can buy any old oddments in a surplus shop with weird or unknown secondaries, the sort that nobody else will touch so they sell cheap, so long as you get two the same . I'm making a low power 230-115 volt stepdown transformer at the moment to run an American instrument using three small surplus 230 volt to 7 . 6 volt transformers . The input transformer is standard 230v to 7 . 6 volt that feeds into two 7 . 6 volt secondaries in series, each receiving 3 . 8volts . The output primaries (now acting as secondaries) are paralleled, so I get 115 volts out . Cheers Billy 8-{) What a good idea . Pity I just dug the trench . I got home and decided, stuff it! so I just got digging . The path is gravel, not concrete, so no big deal, just was more hassle . |
pine-o-cleen (2955) | ||
| 760440 | 2009-04-01 03:41:00 | Went into the council to check about building permits etc, and found out that because I was planning on building the shed close to the boundary, that I would need neighbours permission and a building consent. After digging the trench, laying the cables and re-filling the trench. F%@k! So now I have nicely conduited cables in the wrong place. I have decided to put the shed about 6m away from the house, so your idea Billy T is sounding good at the moment. Tell me if I have this correct. I'd use a step-down transformer to step the voltage down to any low voltage value, and then use the same sort of transformer in reverse to step back up to 230v. Is that right? So for example, I could use two of these: www.trademe.co.nz ...and use up to 100w of power? |
pine-o-cleen (2955) | ||
| 760441 | 2009-04-01 06:24:00 | I don't understand why you would mess about like that for 100 watt power supply in your shed. $42 X 2 + freight would do a lot with proper power. PJ | Poppa John (284) | ||
| 760442 | 2009-04-01 07:58:00 | This is true. | pine-o-cleen (2955) | ||
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