Location for a power inverter - RV-Dreams Community Forum

breckrider · RV-Dreams Family Member

Location for a power inverter

RVDude · RV-Dreams Family Member

3,300 watts (continuous - 6,600 watts intermittent) is a whopping monster - at that 3,300 watt output the input AMPS from the battery will be in the 330amp range. Given your intended use, you would only need some 400-600 watts which gives you easier and more options in mounting.

Search this forum for inverter and you'll get a lot of very good info about them.

SHORT cable length is the absolute rule in low voltage high amp situations. that 3,300 watt output inveter is going to draw 330 amps from the battery and per code is going to take around 4/0 that's 0000 gauge wire that's about as fat as a thumb. You don't want to mount it any further than the (I am sure code inadequate) provided cables.

You said house "battery"? I hope you meant batteries as in 4 or more for that level inverter.

-- Edited by RVDude on Thursday 21st of May 2009 11:01:42 AM

Jack Mayer · RV-Dreams Family Member

The inverter is capable of a quite large output. However, the output is only what the load demands. If you only run a small TV or other ligh loads - not the microwave or other heavy draw items - then the demand on the battery (ies) will not be that great.

HOWEVER, by code the inverter must be wired for the max load. I assume this is a direct wire unit. What is your intention about wiring it? Are you planning to install a sub-panel and power your existing circuits? Are you planning to only power a TV with a separate circuit that you plug the TV into when needed?

The inverter needs to be close to the battery bank - within 5' or so wire run. It must be in a location protected from weather and ventilated well. You can go farther, depending on load, but much farther than that and you start getting into complications with the wiring.

If you paid less than $500 for this inverter then it is what I refer to as a cheap occasional use item. It likely will not operate long if loaded heavily - the cheap inverters (for the most part) as simply not well built. Providing more info on exactly what you want ot power will help with the answers.

You might want to look at my website for some additional info. Just overlook the detailed technical stuff that is not of interest to you.

breckrider · RV-Dreams Family Member

I paid close to $200 for it. I was told by a fellow rv'er that the more amps the better. I plan to run the tv, computers, anything electric except for refrigerator that I can so that I don't have to run the generator until absolutely necessary.

I have just one battery for the "house" part and one for the motor.

The cables are not quite the thickness of my thumb and they're only about 3' long direct connect. I'm going to have to put it some where close to the step well. I just can't decide where then run cords to the tv and computers.

This is what is is...


Description

Item Specifics - Item Condition
Condition:	New

NEW MOBILE POWER INVERTER 3300/6000 WATT DC TO AC nr!!
Brand New In The Box
6000 Watt Peak DC to AC Power Inverter!

Product Specifications:
.: 3300 Watts Continuous Power
.: 6000 Watts Peak Power
.: Low Batter Alarm w/ Auto Shutdown
.: Overload & Short Circuit Protection
.: High Surge Capability (to start motors)
.: Voltage Input Range: 11-15V DC
.: Voltage Output: 115V AC
.: Output Frequency: 60 Hz
.: Modified Sine Wave (MSW)
.: No Load Current Draw: 3A
.: Efficiency: 85%
.: Fuse: 40A x 8
.: Dimensions: 17"L x 7.5" W x 3.75"

If it will run the microwave occasionally, more the better. The reason I want to use this is because we will be parked in the driveway of a friend while at the beach and I don't want to run the generator unless I absolutely have to and I'm concerned about overloading her circuit while running the air conditioner. Plus, the kids can use the tv and xbox while on the road without using the generator.

RVDude · RV-Dreams Family Member

With one house battery you really need to read all the other threads and Howard's and Jack Mayer's info on inverters. No need to repeat all that info. But, you have a non-workable setup. With all the existing house loads, I'm sorry to say, you won't even get one cup of coffee out of that setup.

-- Edited by RVDude on Saturday 23rd of May 2009 07:31:23 AM

Speedhitch · RV-Dreams Family Member

Hey this inverter stuff has me crosseyed! I think the best thing to do is go out and check out some rigs that are rigged out and see what they did to get off the grid....Well that is what I am going to do...I can read Jack and Jeff's advice column all night long and I still am bumfuzzeled on what it all means. I have to have my hands on to understand...good luck I am sure you will get it all to work out.

Speedy

Jack Mayer · RV-Dreams Family Member

I would STRONGLY recommend that you have someone who has some experience in this area design you a proper electrical setup. What you intend to do simply will not work, and could be dangerous. If you are handy and want to spend the time learning then you can figure it out yourself with some guidance. But it is not going to be easy to do yourself.

Terry · RV-Dreams Community Member

If this inverter is just to run the TV and Xbox, all you really need is a good quality 600 watt pure sinus wave inverter. This is all i have in my rv and it works fine for the sat. dish, sat. dish reciever and both tv's. BUT, do note, inverters use a small amount of power at rest and 1 battery holds very limited power.
Regards,

bjoyce · RV-Dreams Family Member

".: No Load Current Draw: 3A"

3 amps of current with no load means it will use 72 amp-hours of battery in 24 hours (24x3) which is more than you can pull out of one battery (40 to 50 amp-hours per day max).

": Voltage Input Range: 11-15V DC"

When the incoming voltage goes to 11 volts DC the inverter will turn off. You will be surprised at how easily that will happen.

breckrider · RV-Dreams Family Member

I don't intend to wire this to run the entire RV. I'm only going to plug in the tv and/or xbox or computer when I need it it. Or the coffee pot. Perhaps I didn't explain it correctly.

RVDude wrote:

With one house battery you really need to read all the other threads and Howard's and Jack Mayer's info on inverters. No need to repeat all that info. But, you have a non-workable setup. With all the existing house loads, I'm sorry to say, you won't even get one cup of coffee out of that setup.

-- Edited by RVDude on Saturday 23rd of May 2009 07:31:23 AM

RVDude · RV-Dreams Family Member

You explained it clearly. I want you to be happy with your project and pleased with the results - but you need to do some homework first. You simply will not be able to run a single battery (unless it is an 8D size) and have it do what you want in any way or any way close to what you want.

How to do it is in previous threads and Howard's and Jack's own web sites. This is not casual reading and is far too much to repeat here.

Good luck!

-- Edited by RVDude on Saturday 23rd of May 2009 01:51:34 PM

breckrider · RV-Dreams Family Member

Where is Howard's website?

Racerguy · RV-Dreams Family Member

Rv-Dreams.com

Jack Mayer · RV-Dreams Family Member

>>> "I plan to run the tv, computers, anything electric except for refrigerator that I can so that I don't have to run the generator until absolutely necessary."
<<<<

Sorry I was confused, but the above statement led me to believe you wanted to run everything in the rig that you could.

If you just want to run one or two items with a separate recepticle for just the inverter then that is relatively easy. I would place the inverter somewhere waterproof and vented, but close to the battery bank - I say bank because you will need at least 2 battereis. ONe battery will simply not cut it.

Then just wire a separate outlet off the inverter for yor coffee pot, and maybe one for your TV. How you route the wires is installation specific so I can not comment on that. But in a class C you can usually go under the rig and then up through the dinette seats, or up into the kitchen cabinets. Put the 120-volt lines in flex conduit (generally the blue stuff you see at Home Depot).

If you are familiar with residential AC wiring this should be a relatively simple job. If you are not DO NOT attempt it yourself. You do need to supply proper fusing if the inverter does not have branch circuit protection, and you do need to supply a DC catastrophy fuse between the battery bank and the inverter. If all of the above sounds like Greek to you, then you need to either study a lot more or - better yet - get some qualified help.

I don't want to scare you, but done improperly installing other than a simple plug-in inverter can destroy items in your rig, or burn it down in the worst case. Also, be aware that working with multiple batteries can be very dangerous - they weld with DC current.....

If you need questions answered after studying your options I would be glad to answer them, or to review any plans you come up with.

-- Edited by Jack Mayer on Sunday 24th of May 2009 08:25:27 AM