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| Thread ID: 78358 | 2007-04-12 12:06:00 | 12v 15A battery lead to car CD player | Strommer (42) | PC World Chat |
| Post ID | Timestamp | Content | User | ||
| 540457 | 2007-04-13 09:42:00 | Tweake and Graham: You must understand that the 1A fuse was with the old tape player and that is gone, so forget the warnings about a 1A rating being pushed to 15A. The wire itself can handle 5A easily, probably 10A or 15A, but remember I have a 5A fuse in the line and it has not blown. And that is the worst that can happen - the fuse will blow. If it does, I will find the current rating for the gauge of wire and put in the appropriate (higher amp) fuse. it does depend on the wiring a bit. some vechiles use really thin cabling. even 5A might be pushing it on some. others use the same cabling on just about everything and are ok for 10A-15A. however thats all in electrical speak, not audio speak. amps can draw peak current a lot higher than the fuse rating without blowing the fuse. my old rule of thumb was to allow 2-3 times the fuse rating. ie 15A fuse, need 30-45A wire. for good audio you work by the peak current not by the average current draw. the other thing to remember is the standard car audio circuit often runs other devices eg cigerette plug, just something to check. and one last thing.....don't forget a decent earth. |
tweak'e (69) | ||
| 540458 | 2007-04-13 12:00:00 | 15A is a serious drain on a piece of wire, even at 12V. Power supplies in a car are apparently naturally very spiky. Although this means that car stereo systems tend to be fairly tolerant, you should not rely on this. I bet you shelled out quite a lot for a new stereo. If you're unsure of how the wiring is organised why not spend a little more to get it installed safely and properly? The worst you can do is not simply blowing a fuse. You could quite easily cause other important electronics to fail. | TGoddard (7263) | ||
| 540459 | 2007-04-13 12:06:00 | How? | roddy_boy (4115) | ||
| 540460 | 2007-04-13 14:03:00 | For one thing if you accidentally connect the positive terminal of the battery to the car's metal body you could cause a short circuit, damaging the electronics or if you're unlucky causing the battery to explode (lead acid batteries produce hydrogen and oxygen - a rather nasty combination if you get a spark). The wire is rated for 5 Amps - that doesn't mean it won't survive a greater load for the few seconds required to destroy something else. The main issue is liability. If a car mechanic stuffs something up and destroys something their insurance will cover it (or they will). If you stuff something up nobody will help you. Car electronics are evil. Balance the risks against the cost of having it installed - is it worthwhile installing yourself? By the stage where I were unsure whether a given wire can take the load three times what it's rated for I would be revising my original estimates. P.S. I may of course be over-cautious. At least unlike many people my age I'm not excessively reckless. |
TGoddard (7263) | ||
| 540461 | 2007-04-13 23:01:00 | For one thing if you accidentally connect the positive terminal of the battery to the car's metal body you could cause a short circuit, damaging the electronics or if you're unlucky causing the battery to explode (lead acid batteries produce hydrogen and oxygen - a rather nasty combination if you get a spark) . The wire is rated for 5 Amps - that doesn't mean it won't survive a greater load for the few seconds required to destroy something else . The main issue is liability . If a car mechanic stuffs something up and destroys something their insurance will cover it (or they will) . If you stuff something up nobody will help you . Car electronics are evil . Balance the risks against the cost of having it installed - is it worthwhile installing yourself? By the stage where I were unsure whether a given wire can take the load three times what it's rated for I would be revising my original estimates . P . S . I may of course be over-cautious . At least unlike many people my age I'm not excessively reckless . It seems you did not read my post above . The stereo is installed and working perfectly, and the head auto electrician at an established business said what I had was OK (I showed him the wiring harness) . I used a multimeter to test the two 12v leads and ground, and had the correct wiring code, using previously installed plugs . Of course your comments are for the wider audience, so I agree: most people should get their stereo installed professionally . BTW, we bought the CD-mp3 player at SuperCheap last Saturday during their 25% sale . At $150 it is a true bargain . Panasonic . Sounds and operates magnificently (although head banging heavy bass boy racers would not be too impressed) . |
Strommer (42) | ||
| 540462 | 2007-04-13 23:27:00 | Forgot to say that the auto electrician did say he got disasters to fix, like when some young hot shot connected a 12v lead to the speakers . I once told a friend of mine that Jaycar had a good deal on multimeters . He looked at me blankly, asking what use they were . . . . groan . . . |
Strommer (42) | ||
| 540463 | 2007-04-14 00:08:00 | It seems you did not read my post above. The stereo is installed and working perfectly, and the head auto electrician at an established business said what I had was OK (I showed him the wiring harness). I used a multimeter to test the two 12v leads and ground, and had the correct wiring code, using previously installed plugs. Sorry, I missed that post :) |
TGoddard (7263) | ||
| 540464 | 2007-04-14 07:05:00 | For one thing if you accidentally connect the positive terminal of the battery to the car's metal body you could cause a short circuit, damaging the electronics or if you're unlucky causing the battery to explode (lead acid batteries produce hydrogen and oxygen - a rather nasty combination if you get a spark). Yes. Using a different wire would fix this of course. I see your point. Oh wait... |
roddy_boy (4115) | ||
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