AC power converter

[MikeyBskunk]

do i need a new alternater to run an AC power converter??

[roach711]

Do you want to CONvert AC to DC or INvert DC to AC?

If you are charging batteries you'll need an alternator or shore power (plug into an AC outlet). The alternator will charge the batteries directly but if you're hooked up to shore power you'll need an AC to DC converter with a battery charger.

Your existing alternator will power a DC to AC inverter - whether you need to upgrade depends on how much juice you need.

Give us a better idea of your present electrical setup and what you want to power and we can be more specific.

[MikeyBskunk]

i want to run the converter to charge my "house" battries wile im driving then use the "house" battries when camping
if that helps any?? i know that the jesperson bus file explanes it better

[gbstewart]

you need a battery isolater, or a solinod. this allowes the house battery to charge when driving, and when that engine is off , it prevents your start battery to discharge.

gbstewart

[roach711]

If all you want to do is charge the house batteries while driving, you don't need a converter at all. The converter converts 120v AC from shore power to 12v DC that you can use to power 12 volt devices or charge the house batteries.

The simplest way to charge your house batteries while driving is to connect them directly to the alternator. The problem with this setup is that when you're camping your starting battery will run down along with the house batteries. To avoid discharging the starting battery you can use a manual disconnect switch (which relies on you remembering to disconnect the house and starting batteries) or as GB said, install a solid state battery isolater or an ignition switch activated solenoid. Both will automatically break the connection between the house and starting batteries while the engine is off and also allow the alternator to charge both while driving.

RV electricity has a pretty steep learning curve.

[lapeer20m]

Depending on how often you use your bus, you may want to consider adding a second engine driven alternator just to run the "house" system and charge the house batteries.

I have had bad luck with connecting battery banks of Different states of charge together. In the past ten years, I have replaced no less than 8 bus alternators due to failure.

In my case, it has proven to be less expensive and less hassle to simply add an alternator and have two separate 12v systems than to wait for my single alternator to fail while on a road trip.

alternators needed in an emergency from a truck stop can be double or even triple the price of the same alternator from eBay.

[lapeer20m]

Also wanted to add that two separate systems provide some great redundancy. If one system fails, they can be temporarily be tied together until it is convenient to fix.

Most bus engines have spare pulleys available on the crankshaft, or other location that make it simple to install a second alternator.

Here is a kink to a video of an alternator I added to a dd rear engine bus.

http://youtube.com/watch?v=l5Uq42x_ES4

[roach711]

Very good point there Lapeer.

[Stuff]

Originally Posted by lapeer20m

Also wanted to add that two separate systems provide some great redundancy. If one system fails, they can be temporarily be tied together until it is convenient to fix.

Most bus engines have spare pulleys available on the crankshaft, or other location that make it simple to install a second alternator.

Here is a kink to a video of an alternator I added to a dd rear engine bus.

video has been took down

[MikeyBskunk]

Huh like said that is alot of thinking and learning but thanks for the tips and keep postion i now will start my serching for supplies

[MikeyBskunk]

soo i have been lookn at the Prowatt sw 2000 inverter and was wondering if anyone knew if that inverter hooked up to 2 RV battries would be sufficent power to power stuff like a mini fridge, stereo, and like a coffie maker, possibly some lights????

thanks


Mike

[roach711]

You'll need to add up the watt draw of each appliance to get an accurate idea of your power needs. There should be a tag on each listing amp draw.

To get watts, multiply amps times volts. Say your refrig draws 2 amps at 120v, so 2 (amps) x 120 (volts) = 240 (watts). Do this for all your appliances and you'll have your total (peak) watt draw.

Of course, you won't be running all your stuff all the time (and the refrig only draws the full 2amps for a second or two at startup) so your average draw will usually be much smaller than the peak draw. Converting AC to DC costs you about 15% so at a hypothetical 1000watt draw you'll be pulling 1150 watts from your battery bank so you'll need to figure out how many watts you consume in an average day and size the battery bank accordingly.

I'm guessing you're going to be tailgating with no shore power available?

[MikeyBskunk]

"I'm guessing you're going to be tailgating with no shore power available?"

that is correct, i go to alot of music festivals that do not provide shore power. I would like to be able to run my fridge all weekend in cases like that.

Thanks for the formula i will have to do some math homework haha

Mike

[logistix]

I have a 6000 watt power inverter and I run a 42" tv, mini fridge, roof mount Dometic AC and 5000 watts of stereo power off of 3 Type 8D batteries with 2 gauge wire and a 250 amp alternator. This is while the bus is turned on. I'm not too worried about an isolator or anything although some people are. Especially if you are out in the middle of nowhere.

The 3 batteries are strong enough to run the AC and TV and stereo for a while, but I never did the math or tested it to see for how long. Instead of wasting diesel where there is no shore power, I just use a gas generator.

[MikeyBskunk]

thanks for the input everyone!