Lights
Never ever anyone should replace fried fuse with different value one. Fuse value has been calculated with certain marginal, if original value is not enough there is shortcut or connection problem that draws more power, if fuse is replaced with higher value one wires could be melt and devices behind that fuse can be set on fire.
Many car fires are caused by bad ground(earth) and then replaced fuse with higher value.
Electric system is very gently balanced and it is easy to upset that balance, when it happens we call it electric problem, so make sure that all parts are in balance.
Water and electricity is basicly working with same principles, car electrics is like complex waterpipenetwork, where small things in one part affect to whole system.
So, better take your multimeter and check where problem is while you still have where to check
Many car fires are caused by bad ground(earth) and then replaced fuse with higher value.
Electric system is very gently balanced and it is easy to upset that balance, when it happens we call it electric problem, so make sure that all parts are in balance.
Water and electricity is basicly working with same principles, car electrics is like complex waterpipenetwork, where small things in one part affect to whole system.
So, better take your multimeter and check where problem is while you still have where to check
Volvo 360GL -88 -under restoration-
Volvo 343DL vario -81 -running-
Volvo 240 Diesel -83 -undecided-
Citroen ZX Dturbo -97 -daily-
Volvo 343DL vario -81 -running-
Volvo 240 Diesel -83 -undecided-
Citroen ZX Dturbo -97 -daily-
Dude, heed the advice, a relay is what you need. Big current WILL melt switches, and when it goes wrong you will have a fire. I made a small school boy error a lil while ago, and was lucky to stop the thing when I just had smoke. This is a big big boy error, correct it now. If you need help, ask, we have enough electronics/electrics/mechanics here.
'89(G) 340 GLE B172k
'03 S60 D5 SE, '91 (J) MX5, 1954 Cyclemaster
Ex:
'89(F) 340 GL F7R (ex B172k) - Fake -> SBKV 300 Runner Up 08, 12; '91(H) 340 GL B14.4E - Kar; '88(F) 360 GLT B200E - Jet -> BKV 300 Runner Up 09; '89(G) 360 GLT B200E - Beast
'03 S60 D5 SE, '91 (J) MX5, 1954 Cyclemaster
Ex:
'89(F) 340 GL F7R (ex B172k) - Fake -> SBKV 300 Runner Up 08, 12; '91(H) 340 GL B14.4E - Kar; '88(F) 360 GLT B200E - Jet -> BKV 300 Runner Up 09; '89(G) 360 GLT B200E - Beast
well, if the fuse goes out when i connect + and -, i dont see the problem.
fire? when i first got the car i drove around with small pieceses of metal instead of fuses. Drove like this for about 2 months before i put in real fuses, and never had any problems...
if you do your calulations correctly, there should not be any problem to put a higher fuse in, instead of putting in a lot of new wires, and external fuses.
have 3 years in school, studying electrics behind me. mostly 230V though.
cheers, but my car is not burning down.
fire? when i first got the car i drove around with small pieceses of metal instead of fuses. Drove like this for about 2 months before i put in real fuses, and never had any problems...
if you do your calulations correctly, there should not be any problem to put a higher fuse in, instead of putting in a lot of new wires, and external fuses.
have 3 years in school, studying electrics behind me. mostly 230V though.
cheers, but my car is not burning down.
don't see the risk if the work is done properly. the 8A course to the right headlight did not take the current from two extra lights. easy math says that 16A should be fine. then i'v calculated that the fuse will go out when + and - is connected. this is done on all the fuses that is higher than original value.
could anyone please tell me how my car could burn down (remember, all wires are extra isolated and fastened just like the should be, and even if it should fall of or somthing like that, the fuse will go out!) ??
cheers
could anyone please tell me how my car could burn down (remember, all wires are extra isolated and fastened just like the should be, and even if it should fall of or somthing like that, the fuse will go out!) ??
cheers
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antiekeradio
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the wire that conducts the current to the headlamps is designed to transport a certain amount of current.
if you put too much current through it, normally the fuse will prevent the wire from melting.
if you put in a bigger fuse you might get a situation that on a full short the fuse still blows (sounds safe, right) but still there can flow too much current to the wires, causing them to heat up. if wires heat up, their resistance rises. the current limiting factor could easily become the wire itself, wich accelerates the heating even further. isolation melts, full short to ground, but fuse does not work! some more melting, and then you have a fire, deep down under your dash/bonnet, mostly right between some unfused wires and ground. (wire looms are bad heatsinks)
same goes for the light switch. its designed to switch, maybe 10 amps maximum, maybe even less. if you overload it, arcing will occur at every switch. switch material (metal parts) will wear out FAST. at some point you only get an arc, instead of a switch. arcs+lots of plastic = ..
if you put too much current through it, normally the fuse will prevent the wire from melting.
if you put in a bigger fuse you might get a situation that on a full short the fuse still blows (sounds safe, right) but still there can flow too much current to the wires, causing them to heat up. if wires heat up, their resistance rises. the current limiting factor could easily become the wire itself, wich accelerates the heating even further. isolation melts, full short to ground, but fuse does not work! some more melting, and then you have a fire, deep down under your dash/bonnet, mostly right between some unfused wires and ground. (wire looms are bad heatsinks)
same goes for the light switch. its designed to switch, maybe 10 amps maximum, maybe even less. if you overload it, arcing will occur at every switch. switch material (metal parts) will wear out FAST. at some point you only get an arc, instead of a switch. arcs+lots of plastic = ..
Agreed with Wouter. You say you can do the maths, and have lots of electrical knowledge, then follow this through.
The wire you have installed the extra lights with is a key factor... if it is higher rated than the 16A fuse, i.e. using V=IR has less than an ohm per distance you have used, then you are indeed correct, the fuse will blow, everybody is happy. And this will only blow if there is a short, but you know what you are doing, so this won't happen.
If you're wire is rated between the current draw of these new lights, and of the fuse (for arguments sake, lets say between 10A and 15A, then if there is a short on these new wires, the fuse won't blow, the wires will get hot, melt through the insulation, and causes arcing to the bodywork (still not enough current can pass through the wire to blow the fuse, but enough to get the battery hot enough to explode), or through a fuel line. But, as we've established, you know what you are doing, so it won't short.
If you're using wire rated under the lights current draw, it's going to get hot and melt anyway.
But, as I've stated, worse case, and anyway, it won't short.
THERE IS ONE THING YOU HAVE FORGOTTEN
The original car lights are wired with wire rated at the current draw of the original fuse (i.e. 8A) plus a safety margin. If a short occurs, the original wiring CANNOT blow the fuse you have put in, the wire has too much reistance. This resistance gets larger with age due to fatigue, not lower, this is why there is a safety margin.
And before you think you won't cause a short, believe me, there are enough wires in the front clusters to get trapped when you adjust the height of the beam, I've done that before now. Thats when you like fuses, when you are under the car tweaking the spotlamps and cannot get out the way quick enough to advoid fireworks. Or when you are doing 70 down a busy road with your girlfriend/wife/pet hamster.
If you think I am missing the obvious, and you know the electrical maths to prove me wrong, then show me. I will quite happily admit myself and everyone else is wrong. Otherwise stop trying to save yourself an hours work. Your car and yourself are worth more.
That post sounds harsh, it was ment to be. Get it sorted.
The wire you have installed the extra lights with is a key factor... if it is higher rated than the 16A fuse, i.e. using V=IR has less than an ohm per distance you have used, then you are indeed correct, the fuse will blow, everybody is happy. And this will only blow if there is a short, but you know what you are doing, so this won't happen.
If you're wire is rated between the current draw of these new lights, and of the fuse (for arguments sake, lets say between 10A and 15A, then if there is a short on these new wires, the fuse won't blow, the wires will get hot, melt through the insulation, and causes arcing to the bodywork (still not enough current can pass through the wire to blow the fuse, but enough to get the battery hot enough to explode), or through a fuel line. But, as we've established, you know what you are doing, so it won't short.
If you're using wire rated under the lights current draw, it's going to get hot and melt anyway.
But, as I've stated, worse case, and anyway, it won't short.
THERE IS ONE THING YOU HAVE FORGOTTEN
The original car lights are wired with wire rated at the current draw of the original fuse (i.e. 8A) plus a safety margin. If a short occurs, the original wiring CANNOT blow the fuse you have put in, the wire has too much reistance. This resistance gets larger with age due to fatigue, not lower, this is why there is a safety margin.
And before you think you won't cause a short, believe me, there are enough wires in the front clusters to get trapped when you adjust the height of the beam, I've done that before now. Thats when you like fuses, when you are under the car tweaking the spotlamps and cannot get out the way quick enough to advoid fireworks. Or when you are doing 70 down a busy road with your girlfriend/wife/pet hamster.
If you think I am missing the obvious, and you know the electrical maths to prove me wrong, then show me. I will quite happily admit myself and everyone else is wrong. Otherwise stop trying to save yourself an hours work. Your car and yourself are worth more.
That post sounds harsh, it was ment to be. Get it sorted.
'89(G) 340 GLE B172k
'03 S60 D5 SE, '91 (J) MX5, 1954 Cyclemaster
Ex:
'89(F) 340 GL F7R (ex B172k) - Fake -> SBKV 300 Runner Up 08, 12; '91(H) 340 GL B14.4E - Kar; '88(F) 360 GLT B200E - Jet -> BKV 300 Runner Up 09; '89(G) 360 GLT B200E - Beast
'03 S60 D5 SE, '91 (J) MX5, 1954 Cyclemaster
Ex:
'89(F) 340 GL F7R (ex B172k) - Fake -> SBKV 300 Runner Up 08, 12; '91(H) 340 GL B14.4E - Kar; '88(F) 360 GLT B200E - Jet -> BKV 300 Runner Up 09; '89(G) 360 GLT B200E - Beast
HeheChris_C wrote:Agreed with Wouter. You say you can do the maths, and have lots of electrical knowledge, then follow this through.
The wire you have installed the extra lights with is a key factor... if it is higher rated than the 16A fuse, i.e. using V=IR has less than an ohm per distance you have used, then you are indeed correct, the fuse will blow, everybody is happy. And this will only blow if there is a short, but you know what you are doing, so this won't happen.
hard to argue with you guys...
anyways, i dont got a lot of electrical knowledge. but i know my ways around high voltage (230V)...
okey, after your fine speach i'll admit, there is a small risk that somthing could go wrong, even though i dont belive it's any big risk..
i can do the maths, but in english
, I=P/U, A=W/C, Ampere=Watt/Current.i'll eat my hat if the car burns down
cheers
As I say, the chance might seem slim but its not only there, it's bigger than you think. Auto electrics is different to standard stuff by the fact it's in an enviroment where extremes are common, and shock forces are going to be large. We just care too much... none of us can stand to see a 300 hurt
'89(G) 340 GLE B172k
'03 S60 D5 SE, '91 (J) MX5, 1954 Cyclemaster
Ex:
'89(F) 340 GL F7R (ex B172k) - Fake -> SBKV 300 Runner Up 08, 12; '91(H) 340 GL B14.4E - Kar; '88(F) 360 GLT B200E - Jet -> BKV 300 Runner Up 09; '89(G) 360 GLT B200E - Beast
'03 S60 D5 SE, '91 (J) MX5, 1954 Cyclemaster
Ex:
'89(F) 340 GL F7R (ex B172k) - Fake -> SBKV 300 Runner Up 08, 12; '91(H) 340 GL B14.4E - Kar; '88(F) 360 GLT B200E - Jet -> BKV 300 Runner Up 09; '89(G) 360 GLT B200E - Beast