24 volt inverters?

[happycamperbrat]

I just want to make sure I got this straight, I have a 24 volt alternator and the 50-60 Vanner which gives me 12 volt for head lights and such. Now my understanding is

1) NOT to touch the batteries or Vanner in order to do a house/battery/inverter system,
2) I need a 24 volt inverter attached to my alternator and another set of batteries like this http://cgi.ebay.com/Magnum-4000-W-Inverter-24-V-105-Charger-more-/250774908231?pt=LH_DefaultDomain_0&hash=item3a63596d47
3) the inverter brands to use are Outback, Xantrex or Magnum (stay away from Chinese made ones)

Will most inverters work with 24 volt solar panels as well as wind power (small windmill when parked sometimes) as well as a big a$$ 24 volt alternator as well as a bunch of batteries wired together to make 24 volt power?

I just want to make sure I am getting all this right...... Thanks!

[Oonrahnjay]

Tell us more about #2, Teresa.  You understand about the need for both a "start" and "house" battery bank and the need to keep them separate, right?

[bevans6]

There is nothing wrong with quality Chinese made inverters, if you buy a quality one.  Xantrex is made off-shore now, for at least some of their product.  I bought a Samlex 3000 watt pure sine inverter, Samlex is a Canadian company that has the product manufactured off-shore.

Brian

[NeoplanAN440]

Yes, you want a separate house battery bank that is disconnected from the coach start batteries when the coach is not running. this way your start batteries will always be charged to get the coach running.
can be done easy with a heavy duty relay , thats controled via the R output on your DN50.

as for size of your house battery bank. you will have to check how much appliances will run for how long.
same goes for the size of the inverter.

in my system , i have a 800 amp house bank build from cheap golf cart batteries. my inverter is a xantrex sw4024. i went this large , because i run a houshold fridge and run the  ac on the inverter while driving .
when driving the 50 dn charges start and house batteries .
when parked , i can run a gen that will charge my housbank via the build in charger in the inverter.

a solar array sized to keep up with the demand for the fridge will also keep my house bank happy and reduces generator times.

some tried to have enough solar to run the ac, but keep in mind that you will need about 2500 watt of solar panels to run one 13k roof ac. thats a lot of space for panels that you need.
about 800 watts keep my fridge and other loads like water pumps, espar heaters and short term use for microwave and other household items.

for wind energy, a cheap starter unit are the air x with 400 watts. they have a build in regulator and a electric brake for these stormy days. i have one now for 6 years and it served me well.

i run my off grid house on only 2500watt array, but thats after a lot of changes in lifestyle and how we use our electricity.

as for inverters.
some cheaper ones will do for easy loads. but keep in mind that brands like xantrex can handle large surge loads and will also hold their rated output. some cheaper units wont hold the rated max for longer then 10 sec.  ( its about how max output will be rated )
also the cheaper units have mostly NO build in charger or the charger has a very low charging rate.
if you have a large battery bank , you dont wanna only trickle charge them, you need real dc amps to get them up.

[Sean]

I just want to make sure I got this straight, I have a 24 volt alternator and the 50-60 Vanner which gives me 12 volt for head lights and such. Now my understanding is

1) NOT to touch the batteries or Vanner in order to do a house/battery/inverter system,

Maybe yes, maybe no.  This is a matter of preference, how you use your bus, and how your generator starts.

I have three battery systems: the original chassis batteries (24-volt, with Vanner), a large 24-volt house bank (also with Vanner), and a 12-volt battery to start the generator.  I have a 250-amp relay that connects the house batteries to the alternator when going down the road.

If I were to do it all over again, I would eliminate the chassis batteries.  I would have a single house bank, which would also run the starter and chassis loads.  It would be connected full-time to the alternator.  There would be no need for the connection relay or for the second Vanner.

The usual reason folks choose to have separate house batteries from chassis/start batteries is to prevent the house loads from dragging the start batteries down so far that the coach can't be started.  However, with a generator like mine that starts from its own completely separate battery, if a single house/start bank was too low to start the main engine, I could simply start the generator, wait until the charger came on for a few minutes, and then start normally.

So it's really up to you.  If you are nervous about messing with the chassis system, or if you will have no other way to start the main engine if your house loads drag the batteries down, then keep the systems separate.  If you do elect to keep them separate, then, yes, they need to be separate at both the 24 and 12 volt points, so the existing chassis Vanner is no help to you on the house side.  You would need another equalizer on the house batteries if you intend to run both 24 and 12 volt loads there.

2) I need a 24 volt inverter attached to my alternator and another set of batteries ...

Your inverter voltage and house battery voltage should be the same.  If you have a 24-volt alternator, then a 24-volt house battery system makes the most sense, and, yes, you would then want a 24-volt inverter/charger.

As far as "attached to the alternator" that is a relative term.  If you have separate house and chassis systems, the alternator will be permanently part of the chassis system, and your house batteries should be attached to it only through either a relay that closes only when the alternator is charging (using the Relay terminal as Peter suggests is one way to do that), or through a "battery isolator."  I recommend the relay method because it gives you a built-in emergency start capability, is smaller, does not require cooling air flow, and does not have the energy losses associated with isolators.

3) the inverter brands to use are Outback, Xantrex or Magnum (stay away from Chinese made ones)

Lots more good brands than just those three. Victron and MasterVolt come to mind, for example.  Besides brand, there are many other issues to consider in selecting an inverter, such as

• "True" sine wave vs. modified sine
• Continuous and surge output rating
• With or without integral charger
• With or without internal pass-through
• One or two AC inputs
• Load sharing capability
• Output boosting capability

When all is considered there are dozens if not hundreds of choices.  Even within a single brand there will be four or five models in your size range.

Will most inverters work with 24 volt solar panels as well as wind power (small windmill when parked sometimes) as well as a big a$$ 24 volt alternator as well as a bunch of batteries wired together to make 24 volt power?

Inverters don't care where the underlying power is coming from, so long as the voltage is within established limits.  However, if the inverter has a built-in charger, the charger's three-stage charging profile might be confused by simultaneous charge from other sources.  Coordinating multiple charge sources to a single bank is a matter of system engineering.

Your underlying nominal battery voltage will dictate the voltage you need for things like solar and wind.  If you have a 24-volt bank you need 24-volt charge controllers and sources.

HTH,

-Sean
http://OurOdyssey.BlogSpot.com

[happycamperbrat]

Sorry guys, I didnt word #2 very well. The way it is worded even confuses me. But maybe I can better clarify here.

2) I need a 24 volt inverter attached to my alternator and another set of batteries like this http://cgi.ebay.com/Magnum-4000-W-Inverter-24-V-105-Charger-more-/250774908231?pt=LH_DefaultDomain_0&hash=item3a63596d47

2) I need a 24 volt inverter like  http://cgi.ebay.com/Magnum-4000-W-Inverter-24-V-105-Charger-more-/250774908231?pt=LH_DefaultDomain_0&hash=item3a63596d47 to hook up to my house batteries.

Tell us more about #2, Teresa.  You understand about the need for both a "start" and "house" battery bank and the need to keep them separate, right?

Yuppers! Actually I will end up with 2 battery systems for the house on the bus when/if everything is said and done (provided I live long enough and finish what I want to do). Im going to have an electric vehicle/toad that will carry most of my house batteries (think of it as a really big battery box). Im also going to have probably 4 12 volt lead acid batteries on the bus which will stay at all times with the bus. The ev/toad has it's own charger (and more then likely, even a different type of battery... not lead acid) and "maybe" a separate inverter will be needed for it.... Im not sure and need to research more before I can say. It requires a 30amp plug. But for right now I want to just concentrate on the 4 batteries actually in the bus at all times and the inverter needed.

There is nothing wrong with quality Chinese made inverters, if you buy a quality one.  Xantrex is made off-shore now, for at least some of their product.  I bought a Samlex 3000 watt pure sine inverter, Samlex is a Canadian company that has the product manufactured off-shore.

Brian

That's encouraging, but I have read some horror stories too......... how do you know which ones are "quality" before they blow up?

can be done easy with a heavy duty relay , thats controled via the R output on your DN50.

in my system , i have a 800 amp house bank build from cheap golf cart batteries. my inverter is a xantrex sw4024. i went this large , because i run a houshold fridge and run the  ac on the inverter while driving .
when driving the 50 dn charges start and house batteries .
when parked , i can run a gen that will charge my housbank via the build in charger in the inverter.

a solar array sized to keep up with the demand for the fridge will also keep my house bank happy and reduces generator times.

some tried to have enough solar to run the ac, but keep in mind that you will need about 2500 watt of solar panels to run one 13k roof ac. thats a lot of space for panels that you need.
about 800 watts keep my fridge and other loads like water pumps, espar heaters and short term use for microwave and other household items.

for wind energy, a cheap starter unit are the air x with 400 watts. they have a build in regulator and a electric brake for these stormy days. i have one now for 6 years and it served me well.

i run my off grid house on only 2500watt array, but thats after a lot of changes in lifestyle and how we use our electricity.

as for inverters.
some cheaper ones will do for easy loads. but keep in mind that brands like xantrex can handle large surge loads and will also hold their rated output. some cheaper units wont hold the rated max for longer then 10 sec.  ( its about how max output will be rated )
also the cheaper units have mostly NO build in charger or the charger has a very low charging rate.
if you have a large battery bank , you dont wanna only trickle charge them, you need real dc amps to get them up.

You are what I dream about! Living off the grid and running WVO in everything! I would love to reach that level of independence one day.

Ive looked into making windmills and they dont seem too hard, just noisey. But a small portable one will probably be okay. I have been the route of exploring loading up with solar panels on the roof to run air conditioners and the cost (in watts and $$$ and roof top space). Im encouraged by thinking one day the price on solar will come down as the technology goes up (like digital watches). In the mean time, there are swamp coolers that use very little juice and are sold for vehicles... since I live in a dry climate at least one will accomodate me and maybe a couple roof tops. At least part of this will probably be run from the large battery array on the ev/toad (which is also where the genny will be). As for the charging inverter opposed to non charging inverter, I guess I will need at least one inverter to be able to charge...... otherwise how would I recharge the house batteries on the bus when on shore power/genny/alternator ?

Maybe yes, maybe no.  This is a matter of preference, how you use your bus, and how your generator starts.

I have no preference or experience, I just want to copy the experts advice. Ideally, I want to be as self sufficient as possible. The generator I have is an Onan 3500 and came out of my old motorhome with a converter. It ran the roof top air conditioner that I also salvaged. My converter/genny/motorhome was hooked up where the start battery took priority of charging before my separate house battery (I think that is the isolator or relay I have read about). Shore power took priority in supplying electric to the motorhome and charging all batteries (house and starter), 2nd was the genny as the priority supply of juice to the entire system and charging, and 3rd was the house batteries (but when on them I could not run my microwave or air conditioner as these were set up strictly AC and the converter made everything DC... but an inverter will turn that around). For the most part, I liked this system but it was all 12 volt system and my understanding is that since I have the 24 volt alternator that I should go with a 24volt system.

I have three battery systems: the original chassis batteries (24-volt, with Vanner), a large 24-volt house bank (also with Vanner), and a 12-volt battery to start the generator.  I have a 250-amp relay that connects the house batteries to the alternator when going down the road.

If I were to do it all over again, I would eliminate the chassis batteries.  I would have a single house bank, which would also run the starter and chassis loads.  It would be connected full-time to the alternator.  There would be no need for the connection relay or for the second Vanner.

The usual reason folks choose to have separate house batteries from chassis/start batteries is to prevent the house loads from dragging the start batteries down so far that the coach can't be started.  However, with a generator like mine that starts from its own completely separate battery, if a single house/start bank was too low to start the main engine, I could simply start the generator, wait until the charger came on for a few minutes, and then start normally

So it's really up to you.  If you are nervous about messing with the chassis system, or if you will have no other way to start the main engine if your house loads drag the batteries down, then keep the systems separate.  If you do elect to keep them separate, then, yes, they need to be separate at both the 24 and 12 volt points, so the existing chassis Vanner is no help to you on the house side.  You would need another equalizer on the house batteries if you intend to run both 24 and 12 volt loads there.
.

Very interesting.... I will give this more thought for the system that is actually on the bus.

As far as "attached to the alternator" that is a relative term.  If you have separate house and chassis systems, the alternator will be permanently part of the chassis system, and your house batteries should be attached to it only through either a relay that closes only when the alternator is charging (using the Relay terminal as Peter suggests is one way to do that), or through a "battery isolator."  I recommend the relay method because it gives you a built-in emergency start capability, is smaller, does not require cooling air flow, and does not have the energy losses associated with isolators.

Good enough for me! A relay it is!

Lots more good brands than just those three. Victron and MasterVolt come to mind, for example.  Besides brand, there are many other issues to consider in selecting an inverter, such as

• "True" sine wave vs. modified sine
• Continuous and surge output rating
• With or without integral charger
• With or without internal pass-through
• One or two AC inputs
• Load sharing capability
• Output boosting capability

When all is considered there are dozens if not hundreds of choices.  Even within a single brand there will be four or five models in your size range.

I understand about pure sine opposed to modified. I also know about stacking the inverters. I "think" only one inverter needs to be able to charge. I understand surge and continual supply. Internal pass-through is not something I am familiar with. I understand about having more inputs on the inverter. What is output boosting capability?

Inverters don't care where the underlying power is coming from, so long as the voltage is within established limits.  However, if the inverter has a built-in charger, the charger's three-stage charging profile might be confused by simultaneous charge from other sources.  Coordinating multiple charge sources to a single bank is a matter of system engineering.

Your underlying nominal battery voltage will dictate the voltage you need for things like solar and wind.  If you have a 24-volt bank you need 24-volt charge controllers and sources.

YIKES! I barely understand the answer here....... I understand that the solar and wind system and battery set up would need to be 24 volt to match my alternator and then a 24 volt inverter. I understand what a 3 stage charging profile is. I dont know nothin about "system engineering", I only know how to copy lol

[garhawk]

There is a multitude of wrongs about a "quality inverter" from China but, ...

[garhawk]

Ooops - Bad grammar!

There are a multitude of wrongs about a "quality inverter" from China, but...

[buswarrior]

Good thing about a giant solar array in an attempt to power the air conditioning?

The solar panels help keep the coach cool with shading...

good topic hcb!

happy coaching!
buswarrior

[happycamperbrat]

I totally agree BW!! Constant shade is a huge plus  If someone was good at soldering and wanted and had the $$$, there are single cells sold on ebay all the time and someone could custom make a strip and/or folding awnings that were made with the cells for additional coverage that the roof alone cannot support.