Am I correct in guessing that if a fella was to run an alternator,without a diode pack,that it would produce 120 volts? Granted,the frequency would depend on the speed. I ask this for a future project....of sorts. Say you did a mount set up on the differential,and wanted to use the A/C current to power a heating element. Say you wanted to use that element to heat some fuel....... Vegetable oil fuel,that is. Broach the subject here iffn' it ain't too O/T,or PM me please. Seems you could do something of this nature as well,if you had a homebuilt vehicle,and needed heat whilst rolling down the road. Maybe in a box or plenum built under the bench seat,with a fan. Talk to me Squirrel!
I have heard about this, I have also heard that it does not give a real steady output but for your purposes, it might just work. You need to supply voltage to the fields (after the regualtor is disconnected) and spin it. Just wondering, Aren't there 12V heaters out there? Maybe the boat or RV guys?
If one needed heat "whilst going down the road"...Motor makes heat - why not leech some from there???
Nope, not even close to 120VAC... The diode pack is a bridge rectifier, not a step down transformer (it takes the full wave AC wave and flips the negative half over to positive, which is "close enough" to DC for a car, not to mention there may be a few smoothing capacitors to smooth the full wave recitifed voltage to a fairly stable level). The output of a bridge rectifier in DC volts is .636 x VACin, so the typical alternator is probably dumping out about 20ish VAC. You could step it up with a step up transformer, but god knows what the frequency would be.
That's a lot of work and engineering to get heat in your car...even I wouldn't go THAT far out into Left Field for it! Seriously, though...I recently installed an aftermarket Mojave Heater in my car and I can tell you it works GREAT! It's compact and self contained with a three speed fan and an optional plenum kit that makes directing the air flow and hooking up a defroster a real breeze. It uses two coolant hoses just like an OEM heater, but the whole unit is small, light and easy to mount just about anywhere. It's designed as an auxillary heater, or one for street rods and small vehicles like pickups...but it keeps me plenty warm in a regular sized, four seater passenger car! You can get them through JEGS mail order...I'm sold on 'em now!
Alternators put out 13-15 vdc because they have a regulator. Bypass it and easily get 120VDC (at high enough rpm). Eliminate the diodes and you've got AC. That's the simple version of the how. The why is your business, but I am puzzled by your solution to get heat. There are better ways, and they only use electricity to run a fan/blower.
Mainly mentioned this,as there has been some discussion here in the past as to where,and what type of heater to install. I think it was mainly on severely channeled vehicles,where firewall and foot room were already compromised. As far as relying on engine coolant as heat,I was trying to come up with something that would heat up faster,and in no way compromise the 'prolly already taxed vehicle electrical system. The vehicle is an '86 model diesel,and I figured something "stand alone" would probably be the best route. As far as the electrical load on it,I would have to do a mockup prior to execution and see what the amp load would be,and if a current limiter of sorts would be required. I decided an A/C current power source would give me more,(read cheaper), options on heater elements,temp controls,and the like. Also figured that,when you stop rolling,the complete system would inoperative,and the system could be enabled by a simple ,single switch. C'mon,tell me more please.
I still don't understand what you're hoping to accomplish in the way of heating your vehicle with some wacky AC-powered french fry maker or something??? The Mojave unit I mentioned is about 6" tall by 8" wide and 10" deep and completely self-contained...easily able to fit into just about ANY interior, cramped or not...and all you need to do is run two coolant hoses from the engine through the firewall and hook up one 12v power supply wire to the three position rotary switch (included) and run the black wire to a good ground. The draw on the vehicle's electrical system from the fan is almost nill, and the coolant gets warm real quick...I go about four blocks and I already got warm air coming out of mine, and after a few miles, it's nice and toasty! For all the engineering involved with trying to make some Doc Brown heating device that uses AC current and only works when the car is moving, I think you'd be happier in the long run with a simple, cheap aftermarket heater unit! Believe me...I was looking for the simplest, cheapest way to add a heater to my car so it could be driven daily even through a Michigan winter (cuz that's what cars are for...you DRIVE them, good weather or bad!) and the aftermarket heater solved my problems! I'll use them in all future projects...you just can't beat the results for the amount of work involved!
He's not trying to heat his vehicle, he's trying to prer-heat heat his vegtable oil bio-diesel so it'll work in the car...
In that case, I suggest (without judging) that there are forums that specialize in that sort of topic. Probably lots of folks have already worked this problem out.
Yup,they have some solutions worked out,however they are stopgap measures at best I think. This was just an idea I was tossing around how to possibly do it better. Who better to brainstorm with,and glean ideas from,than my HAMB bretheren,(and sisteren). Is that a word. No intention to step on any toes,thats why I put "Possibly O/T". Just looking for some electrical info.
How hot do you have to get the oil? I don't think trying to pull any useable AC level out of an alternator is a very practical way of doing it; voltage, frequency, and current capability are all going to be big wild cards IMO. If you absolutely HAVE to use an AC heating element, you'd be better off getting a large DC/AC power inverter that would output a consistant voltage at a specific frequency. If it were me though, I'd try to keep it simple and get a DC heating element... Maybe a heating element out of some car with heated seats? My Lincoln has heated seats and that element probably gets to 150-200 degrees. You could probably snap a couple of those up fairly cheap.
yes, how hot do you have to get the vegtable oil? i know that the big diesel trucks have a heater in their saddle tanks to keep the fuel warm enuff to keep from gelling in the cold...maybe one of them could be adapted? i have no idea what powers them(12 volt dc? ac? propane? ) , maybe one of the truckers on here could tell you
I've been reading 160-180 degrees,and I figured the hotter,the better. Heated seat elements huh,think they get that hot? I'll check on the big rig tank heaters too. I was thinking if I could get it up to 200 degrees in a timely fashion,that would work great. If I could reach 275-300 degrees,I could scoop up and prepare fresh road kill as I see it go down!
I Google'd heated seats and found a couple aftermarket suppliers, looks like "high" temperature on alot of the aftermarket ones are about 140 degrees. Dunno if that would be high enough or if any stock ones would be more, but if you got a few of 'em and insulated the tank to keep the heat contained, who knows. I also happened upon this site too, maybe something like this would also work well for you, they don't cost much. http://www.hydrogenappliances.com/hotwater.html
The main idea is that veg oil is higher viscosity than diesel when its cool. So for it to flow properly, it needs to be heated.
Bugman,yes. The exhaust will be routed in a "U" bend fashion under the tank,in an insulated enclosure. It will enter the front of the bed,"U" under the tank,then exit thru the bed floor. NeverDie,thanks for the link.I'll scope it out.
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