inverter installation........wondering about system "layout"

[mikeylikesit]

Going to take the plunge and add some house batteries and an Inverter.  I am wondering what would be the pros and cons of keeping the new batteries and inverter "separate" from the existing house batteries and existing 110v coach system vs integrating it into the existing system. 

would there be a "conflict" between the power CONVERTER I currently have and the new INVERTER?  or would I disconnect the converter once the inverter is functional? 

would the INVERTER OUTPUT just connect to the 110v distribution panel? I'm reading the tutorials.....I understand the sizing, the battery capacity, etc. 

Probably just overthinking it, (a product of my boating days), but having separate systems and the redundancy it would provide could be a good thing, right? 

 

[HueyPilotVN]

I recently gave my Stacker away, but when I had it I actually had three totally separate systems between the Stacker and the Country coach DP.

The coach system that I still have has a 3KW Invertor/Charger that came from the factory and is intergrated into the distribution panel.  I added 750 watts of solar panels, a networked Blue Sky charge controller system with two controllers, a Blue Sky battery monitor and 4 T-105 batteries.

The Stacker Trailer has two discreet systems.

Each of the systems has a 1KW Invertor/charger and one charge controller each.

One of the systems has 450 watts of solar panels and 4 T-105 wet cell batteries and a trimetric battery monitor.

The other system has 300 watts of solar and 2 Optima Blue top sealed AGM batteries.

I also designed a switching system to allow my golf cart to convert the 6 t-105 batteries from a 36 volt power source into a large 12 volt battery bank.  Using quick disconnect cables I was able to directly interconnect all 14 of the T-105 batteries into a single huge 12 volt battery bank.

The combined systems all charged separately into the combined batteries, with 1500 watts of panels and over 1500 amp hours of batteries.

There is another post on the Forum with more details.

 

[grashley]

Bill has forgotten more on this topic than I ever knew, so my answer is much more simple.

A CONverter takes 120V and makes 12VDC to charge batteries, and the INVerter takes 12VDC and makes 120VAC.  You knew that.  Two different functions.  No direct conflict unless you power the CONverter from the INVerter, which creates a power consuming loop.

In my ideal system, I would remove the "General" circuit from my panel and connect the INVerter to that location, then connect the General circuit to the INVerter through the auto transfer switch.  Now this will only power TV and entertainment systems and plugs and central vac.

I connect the INV to the batteries, which is also connected to the CON and the power panel.  The batteries power the coach and INV. when 120V power is absent.  When 120V is present, auto transfer switch takes the INV out of the circuit, and the CON charges the batteries and powers the coach.

I would keep all the batteries together in one large bank (except chassis battery) to make sure all stay charged and provide the most power available from the INV with minimum battery depletion.

 

[Bobtop46]

Going to take the plunge and add some house batteries and an Inverter.  I am wondering what would be the pros and cons of keeping the new batteries and inverter "separate" from the existing house batteries and existing 110v coach system vs integrating it into the existing system. 

would there be a "conflict" between the power CONVERTER I currently have and the new INVERTER?  or would I disconnect the converter once the inverter is functional? 

would the INVERTER OUTPUT just connect to the 110v distribution panel? I'm reading the tutorials.....I understand the sizing, the battery capacity, etc. 

Probably just overthinking it, (a product of my boating days), but having separate systems and the redundancy it would provide could be a good thing, right?

Inverters can come with automatic relays built in to prevent this conflict, but more importantly the size of the inverter and how you integrate it is the question.  I would leave the converter installed so when you are connected to power it can charge your batteries, depending on how you wire the inverter.  Also depends on if it is just a straight inverter or inverter/charger.

Depends on the size of the battery bank and inverter.  Powering your entire panel from an inverter is difficult because of high power appliances.  Trouble ones are the AC's, microwave, and electric water heater.  The water heater is easy, switch it to propane.  Most people set up a sub panel and move the circuts they want on the inverter over to the sub panel. 


http://www.rvforum.net/SMF_forum/index.php/topic,115752.msg1046557.html#msg1046557

The diagram is off, the black ground from existing system goes to the shunt.  I wired it correctly just have't fixed the diagram.

 

[John From Detroit]

Well the advantage of 2 banks would be if you run either the existing house or the new inverter bank down you still have the other.. The disadvantage is additional cost for more batteries. (you will want more batteries by the way).. I run two banks in parallel.  Connected at the inverter (Lower resistance over all due to more copper.. Expensive copper)

Conflict betwen existing converter and inverter... NOT going to happen

First. in a DC system (The converter/inverter connection is on teh DC side) having multiple sources of power does not matter.. They work it out. Each according to it's ability Or need. The ultimate in communies type communities. Pure socialism at it's finest.. (Very few places does that work out but it does with batteires and converters.

2nd. If you are like me.. I have what I consider to be "The world's best converter" A Progressive Dynamics. IN my case a 9180 with wizard (The 9200 or 4600 lines in fact all the wizard lines are what I call "Best"...  and a Xantrex Inverter/charger. Currently a Freedom 2000xc (DO NOT recommend this model due to 120 volt connections but ... Otherwise nothign wrong with it. If you can make the connections work. More power (2000 watts) to you).

I figured out how to TURN OFF the Freedom's charger (Turns out to be very easy and remotely un-doable) I ran a wire from IGNITION SENSE terminal to the ground lug and menu4 26 Enable.  To enable the charger I just menu 26 OFF and the converter comes on.. Yes. I know. backwards

My old Prosine it was easier. >Toggle switch.

 

[mikeylikesit]

thanks for the replies! Great information, as usual. 


edit: So, looks like the "best" available place for the batteries (4 - T105's) would be under the bench seat on one side of the dinette. Half of it is wasted space anyway, and its adjacent to the bathroom, and right under the breaker panel in the overhead cabinet.  Looks like much of the wiring is already in that compartment.

I've decided to keep the inverter batteries separate from the existing coach batteries. Mostly because there is not room for more batteries up under the hood with existing.

I'm going to go ahead and connect it to the whole breaker panel, mostly for ease of install, and because we won't use the microwave or AC's unless the genset is running. (or shore power)
Fridge only runs on 120v or propane, water heater is LP only.

looking at the Tripp Lite APS2424 Inverter / Charger 2400W 24V DC to 120V AC 14A / 55A Hardwire . I have several friends who have this model and they are all happy with it.

1st challenge is venting the batteries to the exterior of the coach.......I'm sure that is doable.  Then weather/air proofing the compartment so battery gas can't get in the interior.
2nd challenge is getting DW to give up one of her storage compartments.

Is it OK to put the inverter in the same compartment as the batteries?  I guess I could partition it off and seal it (batteries vent to outside, inverter vent to inside) if not.

only thing I'm still a bit unsure of is how the inverter connects to the breaker box.  Inverter has it's own transfer switch.......so does the inverter 120v output connect to the buss bar in the breaker box?  If so, where does it get it's 120v input? (surely there will be a wiring diagram included...)

Thanks folks! 

 

[grashley]

I assume you know you said 24V inverter, so you will wire the battery bank to deliver 24V power.  It appears this unit will also charge the 24V battery bank when shore power or genny is available?

Is your rig 30A (one 120V breaker bank) or 50A ( two separate 120V breaker banks)?  If 30A, just add a breaker to the panel, which will feed the panel.  Make absolutely sure there is an ATS in the system so you are not supplying 120V from the inverter and shore power at the same time!!

 

[mikeylikesit]

Yes, 4 - 6 volt batteries wired to deliver 24 volts to the inverter.

I have a 30 amp service.  so, the existing AC power system has an ATS for the shore power/generator already.........selecting which one to use to send juice to the breaker panel.  I have found that if I start the generator when plugged into shore power, it trips the GFCI adapter I have attached at the end of the shore power cord.....no biggie but I try to NOT do that.

So, now I have 120 volts feeding the breaker panel, either from shore or genny.  Still unclear how to feed the inverter (120v).  Do I disconnect the feed to the breaker box and use that to feed the inverter, and  connect output of inverter to the buss bar? I don't see how it could work any other way.........if I just feed the inverter from a breaker on the panel, it would create a loop where it ALWAYS see's 110v, either from shore power or genny or ITSELF.

I'll be calling the mfg tomorrow, I understand that they have excellent customer support.

 

[solarman]

thanks for the replies! Great information, as usual. 


edit: So, looks like the "best" available place for the batteries (4 - T105's) would be under the bench seat on one side of the dinette. Half of it is wasted space anyway, and its adjacent to the bathroom, and right under the breaker panel in the overhead cabinet.  Looks like much of the wiring is already in that compartment.

Is it OK to put the inverter in the same compartment as the batteries?  I guess I could partition it off and seal it (batteries vent to outside, inverter vent to inside) if not.


Thanks folks!

yes, you can put the inverter in the same location as batteries, if you have active ventilation using a computer fan or the like
to pull clean air through the space. you can do it but I would not recommend it, for peace of mind it's much better if you can isolate the two.
a build up of gasses and a spark from a faulty inverter will give you a serious problem..!

 

[grashley]

You will need a SECOND ATS.  Often, one is built into the inverter.

Power the inverter from your existing power panel through a breaker  AND  24V from the battery bank.  The ATS determines whether to pass 120V through or if it needs to use inverter power.
For the circuits you wish to power from the inverter, remove them from the main panel and move to a sub panel box.  Power this box from the inverter.

Several items should not be on the inverter, including the converter you mentioned, as well as A/C and water heater, among others.

 

[mikeylikesit]

Got it. 

I talked to the tech support at Tripp Lite, and was told that the 120 volts that feed the inverter "pass thru" to the output when the inverters senses 120 volt input.  Basically, it acts as a UPS (because of it's internal Auto Transfer Switch).

It's becoming much clearer.  I had mistakenly thought that the circuits I removed from the primary breaker panel would no longer be powered by generator power or shore power.....but the pass thru feature negates that.

So, a small 4 breaker mini subpanel (box) should do the trick.

1 circuit to the entertainment center c/o (tv, sat receiver, and sat antenna box), 1 circuit to the kitchen counter for a small appliance c/o, 1 for another c/o for phone chargers, and 1 for future.

Now thinking I didn't need this large of Inverter, but that's ok.  Gives me options should I need to McGuyver something out in the boonies......

Thanks all, I'll try to take pics and post as I go.

 

[grashley]

If you plan much boon dock camping, consider adding USB charging outlets powered directly from the battery.  It is more efficient than converting power from 12V to 120V to convert back to 5V to charge the phone.  Granted, it is small amps.  However, it does not rely on the inverter.