electrical experts?

[Craig 94 TA GT]

Can I use a toggle switch rated at 3A 125VAC/1A at 250 VAC for a 12VDC application? I want to use them for some switches in the car (fan switch, e-cutout, etc.), hooked up to the ACC slot in the fuse panel. Could this be done? Thanks in advance.

[pandorasboyfriend]

WIRING

Can you find a higher amp toggle switch? the 250 amp vs. 125amp is a 100% more load. I'm thinking you'll burn out the toggle switch first then probably burn out the fan motor. What gauge wire do you have?

[Craig 94 TA GT]

Thanks for the reply. I figured it might be too low since I've seen most automotive switches rated at 20 amps at 12VDC. The fan switch is actually connected to the PCM, not the actual fans. So I believe it's 18 gauge or thinner wire. My DRLs are using 18 gauge wire, and the E-cutout uses a bit thicker. I needed a "uniform" looking set of switches for these, and the only ones I could find that are compact and similar looking are the ones I mentioned before. 1 is a single pole double throw, and the others are DPDT.

[Jeff_in_Atl]

Can I use a toggle switch rated at 3A 125VAC/1A at 250 VAC for a 12VDC application? I want to use them for some switches in the car (fan switch, e-cutout, etc.), hooked up to the ACC slot in the fuse panel. Could this be done? Thanks in advance.

It depends on the current pull of the device you want to switch.
Here is how you figure it.
amps times volts equals watts
so to refigure what that switch is rated at for 12 volts you have to do a little math.
3amps X 120 volts = 360 watts
360 watts / 12 volt = 30 amps
More than likely your answer is yes.
One more thing to keep in mind is you loose current more at lower voltages in your wire runs. I can't remember the current loss verses wire gage verses length. If you have a devise that pulls 30 amps and you have say 0 gage wire with a length of 1 inch to the switch, the switch is going to have 30 amps going through it. If you have 100 feet of 0 gage wire between the switch and the 30 amp object the switch is going to see a lot more current running through it than 30 amps. This is the reason the power companies raises the voltage to run power line long distances.
http://www.angelfire.com/pa/baconbacon/page2.html

[Craig 94 TA GT]

Thanks Jeff, you da man I really want to use those switches because they're very compact, and can fit in a custom fabricated plate hiding underneath the ashtray. So it doesn't matter about the AC or DC application?

[Jeff_in_Atl]

Thanks Jeff, you da man I really want to use those switches because they're very compact, and can fit in a custom fabricated plate hiding underneath the ashtray. So it doesn't matter about the AC or DC application?

no

[DeWynter]

one could also go with a relay system. tehn you can use a low voltage/amp switch and use the relay to switch your high voltage/amp .

[Craig 94 TA GT]

Thanks for all your guys' help and advice. I installed a new set of switches to match, be accessible, and hidden in the ashtray...so they had to be small. And most of all, I didn't want to cut into any part of the console, or poke any holes. Considering one switch is a SPDT, and two are DPDT, I had to search hard to find matching ones. I'm glad I can use them for this application. I also made a custom plate to fit in the ashtray section, and mounted the switches on it. Here's a pic:

[Blazer]

No you should not use A AC switch on DC the air gap is not that wide it will
work but will not last very long. Go to a parts store an a DC switch.

[Z Ya Later]

That looks pretty cool. Now we just need to fab up a cover with some labels and it'll look super trick. Good job man, I dig it

[Craig 94 TA GT]

No you should not use A AC switch on DC the air gap is not that wide it will
work but will not last very long. Go to a parts store an a DC switch.

Are you sure...I'd really hate to switch them out because they don't make DC switches that small...from what I've seen. What will happen when they fail? Is there a chance of fire or anything catasthrophic? This electrical stuff always gets me a bit worried

[Jeff_in_Atl]

Are you sure...I'd really hate to switch them out because they don't make DC switches that small...from what I've seen. What will happen when they fail? Is there a chance of fire or anything catasthrophic? This electrical stuff always gets me a bit worried

I have never heard of there being any difference in the way and AC or DC switch is made. Actually I've never seen a switch that specified it being a DC switch. Sounds to me like a marketing scheme to sell switches. I've been dealing with electronics in cars for over 20 years. I've burned up a switch trying to pull too much current through it. It melted the contacts together and just wouldn't turn off. I've melted a relay from a bad voltage regulator. I really doubt it would cause a fire. The worst thing is it could melt the switch contacts together and drain your battery.

The switch isn't your biggest problem with the switches you have. The biggest problem is whether the wire gage that you are using is big enough for the current load. Anybody that has ever put a battery in the trunk knows how you have to increase the wire gage to compensate for the added distance to the trunk.

[Craig 94 TA GT]

OK thanks Jeff...I think I understand now. So the contacts would melt internally or externally? I made sure to wrap each external contact with electrical tape. Also, I'm using the exact same wiring previous to changing the switches, so hopefully it'll give me no problems. In case one of the switches does fail and keep on all the time, it's so accessible for me to simply pull the wires, so I don't think it should be too hard on the battery...if I catch it on time.

[Jeff_in_Atl]

OK thanks Jeff...I think I understand now. So the contacts would melt internally or externally? I made sure to wrap each external contact with electrical tape. Also, I'm using the exact same wiring previous to changing the switches, so hopefully it'll give me no problems. In case one of the switches does fail and keep on all the time, it's so accessible for me to simply pull the wires, so I don't think it should be too hard on the battery...if I catch it on time.

Both of the failures I have seen were the contacts sort of arc welded together. The switch body was slightly deformed but not anything close to melting through the case.

The only way to answer whether you might have a problem is to know the current draw of the item you are trying to power. If you are using the original wiring and the wire is like 18 gage you are not going to have a problem with the switches you have. 18 gage couldn't carry enough current to melt a 3amp@125 volt switch.

[Jeff_in_Atl]

Here is a wire gage calculator. Back figure your watts as described above and enter it in the formula. For the heck of it change the length of wire and watch how the wire gage needed changes.
http://www.plattcctv.com/ExternalLin...age_cal.cfm%3F