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| Thread ID: 89681 | 2008-05-08 08:13:00 | Power Supply question. | pine-o-cleen (2955) | PC World Chat |
| Post ID | Timestamp | Content | User | ||
| 667436 | 2008-05-08 08:13:00 | I got creative the other night and decided to build myself a lamp. It's made from welding copper strips that are approx 200mm long and all come together and are soldered at a point and then screwed into some copper plumbing pipe. I have then run some 0.2mm alarm cable up each 'arm'. I intend to use the copper as one side of my DC circuit and the 0.2mm alarm cable as the other. I want to screw in 8 of these (www.dse.co.nz) - one on each 'arm'. Now those bulbs are rated at 6.3V @ 300mA each so in theory I need a 6.3v, 2.4 amp power supply. Now it seems to me that when you get into those sort of amps, that the cost of a power supply rockets. I have a couple power supplies from various gadgets that are no longer used so my question is, will any of these be enough to run such a contraption. P/S 1 : 9vdc 1a; P/S 2 : 6vdc 1a. Now I know that the amps are a bit low, but does the higher voltage on the 9vdc power supply compensate for the lower amps, or is that flawed logic? My next question is, If I use one of these power supplies, are they likely to burn out? Also, is using the copper as one side of the circuit a good idea, or is that too much resistance? |
pine-o-cleen (2955) | ||
| 667437 | 2008-05-08 09:14:00 | why not use led's ?? i think there is led replacement bulbs aldvailable now. | tweak'e (69) | ||
| 667438 | 2008-05-08 09:53:00 | I like the look of incandescent bulbs. | pine-o-cleen (2955) | ||
| 667439 | 2008-05-08 10:45:00 | These are made for your old valve radio dial illumination, so would run (wired in parallel) from the power supply for the valve heater elements ( 6.3v AC if I remember right), see if you can find a transformer from an old radio, or DSE used to carry them (may still do); alternatively you could wire them in series configuration, you'd need about a 230v -> 50v .5a AC transformer or plugpack in that case. | feersumendjinn (64) | ||
| 667440 | 2008-05-08 10:47:00 | Now I know that the amps are a bit low, but does the higher voltage on the 9vdc power supply compensate for the lower amps, or is that flawed logic? That works just as well as going faster when you are on the wrong road. ;) Well, sounds like it is just a fun project, so - - As long as they are simple transformer supplies, you could put your 2 supplies in series, to get a 15V, 1A supply. Add 1 extra lamp. Wire the lamps in series strings of 3 lamps (Each 3 lamp string is about 18V, 300mA.) With a 15V supply, the lamps will last a lot longer, but due to running cooler will drag a bit of extra current. 3 strings placed in parallel will give you 9 lamps taking a total of 900mA plus the extra bit. So, you can run your lamps conservatively to increase their life but run the supply at or above it's rated load with dubious results for the life expectancy; or you could throttle back to 2 strings for a reasonable life for the 6 lamps and the supplies. Maybe, you could throw in a switch to run 1, 2 or 3 strings, bearing in mind that 3 strings with 9 lamps might be pushing your luck a bit with those 2 supplies. If they are more modern switch mode supplies, don't try combining them, the results may well be unpredictable, and the language unprintable. Don't expect to read fine print with this lighting setup though. |
R2x1 (4628) | ||
| 667441 | 2008-05-12 10:26:00 | Thanks R2x1. I decided to just try it out and see what happens. Guess i'll just see how the lamps / power supply holds up, then decide if it's worth 'fixing'. Maybe by then I may have created something more fantastical and this will just be junk, who knows. Finished it tonight, just letting the paint dry. I'll post pics if it dries tonight, or tomorrow. |
pine-o-cleen (2955) | ||
| 667442 | 2008-05-12 10:39:00 | Get the picture now, the wet look is in vogue for designer lamps. ;) | R2x1 (4628) | ||
| 667443 | 2008-05-12 10:40:00 | PS, remember to paint the bulbs a very "light" shade. Sorry. |
R2x1 (4628) | ||
| 667444 | 2008-05-13 06:32:00 | Quite amateurish, but I like it. Attached file: P1110660_sm.JPG (www.imagef1.net.nz) (86 KB) Attached file: P1110661_sm.JPG (www.imagef1.net.nz) (92 KB) |
pine-o-cleen (2955) | ||
| 667445 | 2008-05-13 08:32:00 | That actually looks quite cool. I like the copper color. Nice :thumbs: | beeswax34 (63) | ||
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