Community Forums

magwa1 · 09-20-2009, 10:01 PM

I think I've decided on a Pure Sine (as opposed to modified) inverter in the 2000W range.

For now, and to keep it simple, I think I can find the room for 2 batteries and the inverter in one space fairly close together. And, to keep it *cheap and simple*, I think I'll manually connect my shore power plug to the inverter when it's needed.

I have two questions for anyone that's doing this in a similar fashion: Do I want 2 6v batteries such as the ones in my battery bank now? I see many on the market and I'm flummoxed as to which ones to buy. In fact, I am just figuring that the norm dictates good sense. And the norm for house batteries is 2 6V deep cycle batteries. So, which ones are best? I see some rated at ~250AH for about $110. Do I need 4 for long boondocks? I know, that's a stupid question to ask. The proper answer is always, "How much are you going to use?" I guess I'm just looking for anecdotal answers. I'm using satellite box, 2 TV's, (neither more than about 1 hr/day) lights at a minimum, sat. finder, water pump on and off when required (2 people), frig igniter only, water heater igniter only, and radio pretty often...but I think that runs off of the auto battery. I bought a Watt use gage today, so I'll know my peak and AH use after testing and adding up the use. But for now....Any thoughts?

Next, what about a charger for the batteries? Something I can leave attached to the batteries and plug into an "on board" shore power socket when "docked"?

Is that more than three questions?

Thanks.

Bob (WA0MQE) · 09-21-2009, 06:25 AM

Two batteries is not enough, trust me. You will need at least four batteries. And, if you plan on boondocking very much you should, if you don't already have them, get some good sized solar panels.

garym114 · 09-21-2009, 08:30 AM

For the AC loads you listed, TV's , sat finder, probably a sat receiver a 2000w inverter is probably overkill. You will want some receptacles for charging laptop ect.
Are you going to string extension cords or install a sub panel for inverter loads?

magwa1 · 09-21-2009, 09:09 AM

First, I intended to "plumb it in" to the system. I think the Prosine inverter has a built in switch that reads whether shore power is connected or not and directs current accordingly. It also has a charger. So, without seeing it, I'll assume that the connections and switching would allow recharge from shore power when "hooked up"

When I started all of this, I called an RV place here in California's Central Valley. They listed parts and costs that came up to over $5,000. Including "$800 - $1,000 for wiring". So I wouldn't do it. Then, I figured that if I overkill on the safety side, "how difficult could this be?"

I'm now planning to place an electrical plug-in box in the shore power chord area and hard wire that to the inverter with the proper gauge wire. Depending upon the advice here, I'm looking for the right spot for the batteries and inverter so that they are close, and I have some air flow around the inverter and access to the battery bank. I don't know why, but I really feel it would be good to isolate the inverter battery source from the current house batteries. That system is really good, of course has the genset and a small solar system connected for charging. So, I don't want to mess up something that is already working perfectly.

Without getting too complex (so I can do it myself), I'd like to make sure that I can get a charge on the inverter bank of batteries using the Prosine system I'm looking at on ebay. Of course, I'd like to have an automatic change-over from shore to inverter power. But, as I said, I have to keep it simple to stay close to my knowlege-base...Hahaha!!!

Frankly, although I'm not cheap, I can't abide by going in to someone who wants to retire of on my already "broken" 401k... just to wire me up... when I think I can do it myself with the proper education and investigation. Professionals should be used when needed. I've seen a lot of DIY jobs on a lot of things that are laughable. But, with proper care and an eye and hands on detail, this has to be do-able.

So, until I get some more input from you folks, or directions from you to someone who's got the info, I'm planning on buying an inverter that is bigger than I need, getting a bank of batteries (4 - 6's, I guess, huh? two in series, two parallel?) wired up to the inverter, wiring up "Romex" or whatever proper wire to a simple plug in box in the shore power compartment. Then, unless I get feedback to the contrary, I'll run a charger between the battery bank and an existing plug-in that is hot when on shore power.

Thanks in advance for any more suggestions or directions.

DAN L · 09-22-2009, 01:47 AM

Quote:

Originally Posted by magwa1

I think I've decided on a Pure Sine (as opposed to modified) inverter in the 2000W range.

For now, and to keep it simple, I think I can find the room for 2 batteries and the inverter in one space fairly close together. And, to keep it *cheap and simple*, I think I'll manually connect my shore power plug to the inverter when it's needed.

I have two questions for anyone that's doing this in a similar fashion: Do I want 2 6v batteries such as the ones in my battery bank now? I see many on the market and I'm flummoxed as to which ones to buy. In fact, I am just figuring that the norm dictates good sense. And the norm for house batteries is 2 6V deep cycle batteries. So, which ones are best? I see some rated at ~250AH for about $110. Do I need 4 for long boondocks? I know, that's a stupid question to ask. The proper answer is always, "How much are you going to use?" I guess I'm just looking for anecdotal answers. I'm using satellite box, 2 TV's, (neither more than about 1 hr/day) lights at a minimum, sat. finder, water pump on and off when required (2 people), frig igniter only, water heater igniter only, and radio pretty often...but I think that runs off of the auto battery. I bought a Watt use gage today, so I'll know my peak and AH use after testing and adding up the use. But for now....Any thoughts?

Next, what about a charger for the batteries? Something I can leave attached to the batteries and plug into an "on board" shore power socket when "docked"?

Is that more than three questions?

Thanks.

plz add what kind and year, etc your moho is to your signature box. that info will help us answer your questions intelligently.

Gary RVRoamer · 09-22-2009, 11:24 AM

For what you have described, a 2000W inverter is way overkill and two batteries is plenty, especially since most of the loads you listed (12v lighting, water pump, etc) will draw from the house bank, not the inverter. But have you considered that you might like to run an electric coffee pot or the microwave? Once you have the 120v power, you tend to use it for more things. But if you estimate is accurate, then a 1000 or 1500 watt inverter is plenty.

The Prosine is available as standalone or with an integrated 100A charger. The integrated charger model has the transfer switch as well, so you get both in one package. The charger charges whenever it has 120v available to it, so it will take care of the batteries as long as you plug in often enough. The transfer switch, however, is of no benefit in your wiring plan - it is there to switch the loads powered by the inverter over to the regular house 120v system when shore power is available. You will be doing that by plugging the shore cord, so the switch is useless to you. The switch is not part of the charging system and serves no function there.

Keeping the inverter battery bank separate from the rest of the house is a personal choice. There are very minor pros and cons each way and its hardly worth the space/time to list them, let alone debate. Do what you like.

As for the type of battery, the 12v golf cart type is an excellent quality deep cycle. A pair of them (Trojan T105 or Interstate U2200) will give you 220 AH. The slightly larger U2600 or T108 is about 240-250 AH.

Always-RVing · 09-22-2009, 11:49 AM

Hmmm,,,, Is there another reason for Inverters than providing 110vac to devices from your batteries? If you really use the batteries for 110v devices, wouldn't the batteries be sucked dry in minutes.

magwa1 · 09-22-2009, 01:12 PM

Quote:

Originally Posted by DAN L

plz add what kind and year, etc your moho is to your signature box. that info will help us answer your questions intelligently.

Okay. Thanks.

Let's see...Did this work?

magwa1 · 09-22-2009, 01:37 PM

Thanks, Gary.

This illuminated (sorry for the pun) something for me. Even with the shore power plugged in, the system takes the shore power and simply charges the house batteries...The source of juice for the lights, water pump, and ceiling fans is still 12V coming from the house batteries, huh?

That makes sense. They are 12v utilities. So, what I'm doing in plugging in the shore power to the inverter is just "hotting up" the 110 plugs (black faced switches/plugs in my MH..maybe everyones?), and the hard-wired appliances like the frig and the micro and micro fan.

As you said, if I only use the 110 plugs with loads as I stated, and switch the fridge to gas, and forget the AC, 2.0kw or 2.5kw *would* be overkill. But if The Boss cranks up the hair dryer (draws 1410w constant - measured yesterday), or the micro, then I guess I'd rather go too big than too small.

And getting a unit with a switch would allow someone smarter than I am to later plumb the inverter into the system...I'm afraid I know my limitations...But, it seems if I'm hunting out a source for 110 to start with to use an inverter with an integrated charger, then why not go all the way and just get the shore power plumbed into the system to start with?

I suppose that buying a 1500w Pure Sine inverter, two 12v batteries placed in parallel, and a separate charger (that plugs into a 110 plug using shore power) is closer to my capacity to install. And probably cheaper, too.

I guess I'd have to have a remote on the charger to turn it off while on the inverter is sending out 110v. Pity, I guess the inverter can't charge itself.... (that part's a joke). I bet if I left the charger plugged in to a 110v socket in the MH that the inverter is trying to fire up, something bad could happen.

Thanks so much for the tips.

garym114 · 09-22-2009, 11:05 PM

You should probably go to the Xantrex site and take a look at what you are considering. You can download the install guide and instructions to see what is involved.
I installed a Xantres 2000 watt inverter and a combined 100amp battery charger and in the process added 4 more 6v batteries. All is operated from a remote panel which also gives the condition of the batteries. Not connected to AC, when we need AC for something I turn the inverter on at the remote panel. Without any AC loads the inverter still draws power so we turn it off when through. When connected to AC or the gen is running the inverter senses the AC and passes it through to a subpanel. It doesn’t have to be turned on to do this. With AC if I need to charge the batteries I turn the charger on at the remote panel and the batteries are charged with the three stage charger.
The AC to the inverter/charger is from a 30 amp breaker in my main breaker box. That is the AC that is passed through and supplies the power to operate the charger. All inverter AC output goes through a 20 amp and a 15 amp breaker built into the inverter and on to a sub panel. The only AC loads in the MH that are still in the main breaker box are the front and rear A/C’s , water heater, refer, inverter power and two more outlets I installed that don’t go through the inverter. All the other breakers for all outlets in the MH I removed from the main breaker box and put in the sub panel, even the outlet for the microwave. We have a hair dryer, two heat settings, 600 and 1000 watts. Try to find her one of those. Operating 1410 watts from a 1500 watt inverter is to close to the max capacity.

magwa1 · 09-22-2009, 11:52 PM

Great. Thanks. Much great info. Also, the piggy hair dryer goes. I think, after looking at it today, a 600/1000w drier will work just as well. You should have seen the "blockage"!! Hahaha. Now, for digesting the switching/charging/110 circuit sourcing. Spent some time measuring for batteries today. A couple of spots. But I've read that they have to be close but not too close to the inverter (heat, explosive fumes, etc.), and each in some sort of reasonable and separate air-flow spot. Lots to consider. But with all of your help, I'm getting there. Thanks again to one and all.

DAN L · 09-23-2009, 12:15 AM

Quote:

Originally Posted by magwa1

Great. Thanks. Much great info. Also, the piggy hair dryer goes. I think, after looking at it today, a 600/1000w drier will work just as well. You should have seen the "blockage"!! Hahaha. Now, for digesting the switching/charging/110 circuit sourcing. Spent some time measuring for batteries today. A couple of spots. But I've read that they have to be close but not too close to the inverter (heat, explosive fumes, etc.), and each in some sort of reasonable and separate air-flow spot. Lots to consider. But with all of your help, I'm getting there. Thanks again to one and all.

agm batteries like lifeline batteries require very little venting. kinda expensive though. i got mine from bd batteries online.

Gary RVRoamer · 09-23-2009, 09:11 AM

Quote:

Even with the shore power plugged in, the system takes the shore power and simply charges the house batteries...The source of juice for the lights, water pump, and ceiling fans is still 12V coming from the house batteries, huh?

Not exactly. The inverter/charger (or converter/charger, if no inverter) is pumping out somewhere around 13.6v most of the time and it goes into the 12v system. If a 12v appliance is running, it sucks that juice right out and it never reaches the batteries. As 12v power demand falls off, any excess capacity goes to charging the batteries, if needed. By the same token, if the demand exceeds the inverter or converter output, the extra is taken from the batteries. Both the inverter/charger and the batteries feed the 12v system and the system does not know or care where it draws from - it's all just "12v".

magwa1 · 09-23-2009, 10:09 AM

Quote:

Originally Posted by RV Roamer [Gary]

Not exactly. The inverter/charger (or converter/charger, if no inverter) is pumping out somewhere around 13.6v most of the time and it goes into the 12v system. If a 12v appliance is running, it sucks that juice right out and it never reaches the batteries.

Gary,

Does that mean that, with a system that has only a converter/charger, even if you are plugged into shore power, but enough 12v appliances are "on"...(lights, water pump, etc.), your house batteries could potentially get no charge and eventually go bye-bye?