Inverter, magical solution, or evil battery destroyer?

[K1ngN0thing]

I mean the house battery. I also have another house battery that is not connected with that one. So battery 1 powers 12v, and I want battery 2 to power 120v ac by hooking my shore power cable to the inverter it's connected to.

 

[K1ngN0thing]

To simplify, let's say I just had the one house battery, and I plug into shore power. Would I be able to use that battery for 12v applications while using the shore connection for AC applications if I turn off my converter, so the shore power isn't converted to DC and doesn't charge my house battery?

 

[sushidog]

Sure. That would work. Just pull your 12v fuse on the converter while leaving the a/c breakers operative. Is there reason to believe that if the converter is providing both ac throughput and DC charging that it would exceed the capacity of the converter?

I intend on building a TT which has 3 electrical systems, a 12v dc, a 48v dc and a 120v ac. You can isolate any battery bank you like or have them overlap too. There are even new inverters that will allow the inverter to add a/c current to low amperage shore power, say when moochdocking with a small extension cord, but a high amp draw like air conditioning is needed.

Chip

 

[Sabatical]

@kingnothing
Yes. Your battery can power both 12v and 110v through your coachs power center by plugging the shore whip into your INVERTER that is connected to your house battery. I had to unwire my converter as the breaker did not cut all power going to it. You maybe could wire your two batteries parallel if they were near each other thereby giving you more ah at the same voltage. It's not good to hook two batteries together that aren't the same age and shape but if you need it and that's what you have then give it a shot.

 

[Canine]

Would 48 volt DC inverted to 110 volt AC be more much more efficient than 12 volt DC to 110 volt AC?

My understanding is transforming from 48 volt DC to 12 volt DC is very efficient, so if 48 DC to 110 AC is significantly more efficient, then that would open up more options with electrical devices. Lots easier to find a hot pot, a microwave, or other appliances in 110 volt AC that 12 volt DC.

 

[highdesertranger]

K1 I am kinda confused about all you are asking. "I want to route my shore power cable indoors to connect to my inverter" I don't understand this. your invertor runs off of 12v not 120v, do you mean your converter?

"While that battery and inverter are providing AC power, will I be able to utilize DC power" the short answer is yes you can run both your invertor and your 12v side.

"If I turn the converter off, will I be able to, say, use DC for the lights, water pump, etc, while simultaneously nuking a burrito?" I have never seen a converter that you can switch on and off, it's automatic when you plug in and unplug.

a converter is like an onboard power supply it takes 120v and converts it to 12v it also has a battery charger(barely) to charge your house battery.

an invertor takes 12v and inverts it into 120v. two totally different things here. highdesertranger

 

[highdesertranger]

ok I posted without reading page 3, duh. so let me try again. you want to take the 120 from your invertor and plug it into your 120v shore power input, right? yes I could see this being done just make sure you are not powering your converter, that would make a loop in your system at the very least it will kill your batt pretty fast. you are going to have to make sure that your 120v to the converter is cut but that the 12v side still works. I don't know what converter you have or how it's wire but it shouldn't be to hard to figure out. highdesertranger

 

[sushidog]

The inverters I looked at are only 1-2% more efficient, (within the same brand) comparing 12v to 48v models. The biggest advantage is being able to use much smaller wires, especially at high voltage, high wattage applications (over 2,000 watts).

The reason I'm going to have a 48v battery bank is to run a 48v dc native super high-efficiency air conditioner. I will lose less power with smaller wires from my solar panels to the charge controller and will save money on using a lower amp rated charge controller too. For example, a Tristar TS-MPPT-45 solar charge controller will only handle 600 watts of solar power at 12v, but will handle 2,400 watts at 48v.

Chip

 

[akrvbob]

Is there a reason you want to do that? If it were me I would just bypass the converter all together by plugging a powerstrip into the inverter and plug my 110 items into it.

I don't know enough about converters to know for sure, but taking power out of the battery, running it through the inverter and then running it through the converter to distribute it through the RV seems like it has to waste a bunch of power. Does the converter warm up when you plug it into shore power? If so that is wasted power.

Unless you have a Pure Sine inverter, how is the converter going to like the quality of power it gets from the inverter?

When it comes to electriciy I think simple and certainty are better, and this is plan is the opposite of simple and has a lot of unknows. I don't like unknowns when a wrong guess can burn my home down and kill me.

But maybe that's just me.
Bob
Bob

 

[SternWake]

Most RV converters are wired right next to the 12v and 120v distribution panels.
However
12v loads when not plugged in do not run through the converter. The converter is like a charger whose alligator clamps are on the battery, but the power cord is not plugged in.

With Inverters, some RV's have automatic transfer switches. I cannot claim any familiarity with these devices or their specific method of operation. The Inverter should never power a converter. Unplug it / flip the breaker for it, if there is a concern that it will be powered by the inverter.

Think about it, the converter is a battery charger. the inverter is a battery depleter. using one to power the other on the same battery bank at 85% efficiency on the 120v to 12v and then only 855 at 12v to 120V, simply wastes battery power as heat.

 

[K1ngN0thing]

Most RV converters are wired right next to the 12v and 120v distribution panels.
However
12v loads when not plugged in do not run through the converter. The converter is like a charger whose alligator clamps are on the battery, but the power cord is not plugged in.

With Inverters, some RV's have automatic transfer switches. I cannot claim any familiarity with these devices or their specific method of operation. The Inverter should never power a converter. Unplug it / flip the breaker for it, if there is a concern that it will be powered by the inverter.

Think about it, the converter is a battery charger. the inverter is a battery depleter. using one to power the other on the same battery bank at 85% efficiency on the 120v to 12v and then only 855 at 12v to 120V, simply wastes battery power as heat.

I have two battery banks (1 battery each) so I wouldn't be making a closed loop. I just wanted to make sure I could use both batteries simultaneously for 12v and 120v respectively, which looks to be possible as long as I'm not powering my 12v outlets with my inverter's output, which means I'll need to flip the breaker on my converter.

Is there a reason you want to do that? If it were me I would just bypass the converter all together by plugging a powerstrip into the inverter and plug my 110 items into it.

I don't know enough about converters to know for sure, but taking power out of the battery, running it through the inverter and then running it through the converter to distribute it through the RV seems like it has to waste a bunch of power. Does the converter warm up when you plug it into shore power? If so that is wasted power.

Unless you have a Pure Sine inverter, how is the converter going to like the quality of power it gets from the inverter?

When it comes to electriciy I think simple and certainty are better, and this is plan is the opposite of simple and has a lot of unknows. I don't like unknowns when a wrong guess can burn my home down and kill me.

But maybe that's just me.
Bob
Bob

I do have a pure sine inverter, but I don't want to convert it to DC at all. Reason I want to run my shore cable to the inverter is convenience. My microwave's too far from the inverter to use without running an extension cord through the middle of the aisle. I guess I just have to figure out how my converter works and what breaker to flip so there's no conversion going on.

 

[highdesertranger]

I am totally confused, and I thought I had it.
one more time an inverter takes 12v and converts it to 120v. the only time 12v is involved is on the input side. an inverter does not put out 12v. perhaps a diagram. maybe I am missing something. highdesertranger

 

[K1ngN0thing]

I want to power my 120v AC house outlets with battery b while simultaneously powering my 12v house outlets and functions with battery A. Batter A is the one that came with the RV and is connected to the converter.

 

[akrvbob]

My microwave is also at the back of the van and my inverter is at the front. Because I much prefer simple to complicated, I just took my 10 gauge 110 volt extension cable and ran it to the back and plugged the micro into it. Very simple and I had the cord anyway.

Unless you have plenty of power to possibly waste by running it through both the inverter and converter, I'd suggest you do the same.

I'm sorry, but I know too little about inverters to answer your questions.
Bob

 

[akrvbob]

I am totally confused,  and I thought I had it.
one more time an inverter takes 12v and converts it to 120v. the only time 12v is involved is on the input side.  an inverter does not put out 12v.  perhaps a diagram.  maybe I am missing something.   highdesertranger

If I understand right, he wants to get 110 volt from the inverter to power his microwave. But the microwave is in the back and he doesn't want to run an extension cord through the van.

He wants to plug the microwave into his Class B existing wiring and then plug the converter into the inverter. That way the microwave works and he doesn't have to run an extension cord. 

He just wants to use the exiting wiring by powering the coach from the inverter.

I'm satisfied this is a bad idea, so I haven't tried to sort out the Battery A and B question.
Bob

 

[jimindenver]

he doesn't want to plug into the converter into the inverter, he wants to use the shore power plugged in to the inverter to energize the outlets and run his microwave. As long as he can turn off the converter it will do just as he wishes. Leave it on is not a good idea at all.

 

[akrvbob]

This is where my ignorance of RVs comes into play. Doesn't the plug for shore power go to the converter?

How can you bypass the converter to energize the rest of the wiring?
Bob

 

[highdesertranger]

well Bob don't feel ignorant I know RV's and I am confused. highdesertranger

 

[jimindenver]

In my trailer the shore power cord goes into the power center distribution center with breakers. One of those breakers feeds the converter that in turn charges the battery and provides 12v power to the trailer which has it's own fuse center for the various 12v loads. There are also breakers for the A/C, microwave, outlets and 120 Vac side of the fridge too.

So just because the cord is plugged in doesn't mean the converter is on.

 

[akrvbob]

Okay, I see. He has a class B so I wonder if it is the same thing?

If so then it should work. But I would still just use an extension cord! A 2000 watt pure sine burns a lot of power not even running, you would only want to have it on when totally necessary.

Getting back to Sterns Original Post, you want everything that possibly can be converted to 12 volt and minimize 110. It seems like extra work for very little gain.
Bob