Ignition Switch Wiring

I have a 2002 Ford Taurus and am in the process of installing a 30 amp relay under the hood for an accessory. Could someone tell me where to find the ignition switch wire that works ONLY when the ignition is on? I have a good idea about working with other 3 wires going to the relay...just don't know where to look for that ignition wire. Thanks in advance.

hello,why not just hook into the fuse box??not all are hot with the key on but some are.good luck

hello,why not just hook into the fuse box??not all are hot with the key on but some are.good luck

Thanks for the suggestion...I found a 15 amp fuse that just works when the car is on. I'm in the process of hooking up a hydrogen fuel cell. Do you think there would be any problem with using a 10 amp add-a-circuit and running through a 30 amp inline fuse to the generator? Or would the 10 amp fuse blow because the 30 amp inline was between it and the generator? I'm not too sure if there is any conflict between the two amperages.

i think it would be alright.someone else may no better

It probably won't matter because after a week, when you realize the fuel cell doesn't work, you'll remove the whole thing anyway. ;)

I'm not quite following what you're doing with the 10-amp inline fuse. If it will be in series with the 30-amp fuse, the 30-amp fuse will never blow. Your circuit will be protected for a 10-amp current draw. If you're wanting to use a fuse holder intended for a 10-amp fuse and put a 30-amp fuse in instead of the 10-amp, you would run the risk of the wire melting under a continuous 30-amp draw. Melting wire plus potential for hydrogen vapors = not good.

If you're wanting to use the 10-amp inline fuse to the coil of the relay, then powering the relay contacts with a separate the 30-amp protected circuit, you'll be fine. The relay coil will not draw anywhere near 10-amps, and the purpose of a relay is to allow a low current source to switch an isolated higher current source.

Honestly though, consider looking at some of the truly independent reviews on the add-on hydrogen fuel cells if there's a chance you can get your money back for the kit. Besides, if it were really this easy to improve fuel economy, power and emissions, don't you think the manufacturers would be using these?

-Rod

A relay only uses a tiny bit of amperage to energize it, so I suggest finding a source on the fuse panel. Most relays draw less than 0.2 amps, so adding the relay to an existing circuit shouldn't affect it.

I don't understand your question, though. A hydrogen fuel cell is a complete vehicle engineering design that uses compressed hydrogen to generate electricity for an electric motor by inducing an electric potential over an electrolytic membrane. You can't magically add that to an existing car. If you are designing a hydrogen supplementation system using brown's gas, HHO, or anything involving a quart jar and water, save your money. The law of conservation of energy is the first and most fundamental truth of chemistry and physics. Breaking that law is impossible regardless of what website tells you it can be done.

... and I'm a libertarian who believes in conspiracy theories. I'm also a scientist who knows that all of the laws of physics have yet to be defied.

It probably won't matter because after a week, when you realize the fuel cell doesn't work, you'll remove the whole thing anyway. ;)

I'm not quite following what you're doing with the 10-amp inline fuse. If it will be in series with the 30-amp fuse, the 30-amp fuse will never blow. Your circuit will be protected for a 10-amp current draw. If you're wanting to use a fuse holder intended for a 10-amp fuse and put a 30-amp fuse in instead of the 10-amp, you would run the risk of the wire melting under a continuous 30-amp draw. Melting wire plus potential for hydrogen vapors = not good.

If you're wanting to use the 10-amp inline fuse to the coil of the relay, then powering the relay contacts with a separate the 30-amp protected circuit, you'll be fine. The relay coil will not draw anywhere near 10-amps, and the purpose of a relay is to allow a low current source to switch an isolated higher current source.

Honestly though, consider looking at some of the truly independent reviews on the add-on hydrogen fuel cells if there's a chance you can get your money back for the kit. Besides, if it were really this easy to improve fuel economy, power and emissions, don't you think the manufacturers would be using these?

-Rod

Thanks for your input...personally, I think that the manufacturers would be putting their heads on chopping blocks by going against the oil industry. I do know a mechanic who is experimenting with these. I didn't buy a kit either...I came up with a design that would fit under the hood with limited space.

"Murf," in case this is still a problem (I see this is an old "thread"), you might try an oil pressure switch arrangement (use a relay after the switch, too).