Inverter/Charger or separate components?

kaipo_boy

I'm sure this has been hashed through before, so feel free to point me in the right direction to read up on it... although, in my own defense there are a lot of new items on the market so the new capabilities for new components are constantly changing.

I've noticed that the people who seem to be frequent posters here and familiar with these systems are using integrated inverters/chargers (the Outback name pops up a lot, along with Magnum and Xantrex) as opposed to the way I went, which is a separate inverter from Cotek and a charger from Meanwell and Iota. The reason I went that way was the cost was very low (primarily) and quality/reliability still seems very high. I'm starting to see now that inverters like a 'range' of voltage within which they are comfortable, so the charge profile you are using with the charge controller may or may not be compatible; this is also true of your battery charger, of course; not to mention my Meanwell needs to have the loads turned off before it will do its job well (i.e., have to turn off the inverter while the charger is on). But assuming you could pick and choose carefully enough and work through these little niggling details, this is a rather minor detail you could work through and save a ton of money as the integrated inverter/chargers all seem rather pricey. So, what is the rationale behind going with an integrated inverter/charger from, say Outback or Xantrex? Is there something else here that I'm missing?

This is not just a rhetorical discussion, I've located a 875ah 24v lift battery that is perhaps 5 years old and thinking about picking it up (no price yet). IF I can snag it for relatively cheap, my next considerations will be the other components needed for it... which is why I'm playing with the above discussion.

SolarPowered

Depends on the load demands you require. There is nothing wrong with Cotek or Meanwell. The only difference is the ones you purchased are better suited for mobile/automotive applications.
Other types such as magnum/outback/Xantrex are better suited for home use.

Home/off grid inverters have a tendency to be more efficient on loads, VS mobile application inverters.

Cost ultimately plays a huge factor, but if it works, then it suits it's purpose.

mike95490

How many watts can a "stand alone" charger provide to your batteries ? Less than 2,000 watts usually, since that's often the limit of a household circuit. The integrated chargers in an inverter can usually supply several times that amount. That's a Big Deal to reduce charging of a large battery bank

My 48V 15A IOTA = 800w ( with a 20A 120V plug on it's power cord)
My 48V inverter charger on a 10KW generator, 100A (4,000w)

vtmaps

kaipo_boy wrote: »

my Meanwell needs to have the loads turned off before it will do its job well (i.e., have to turn off the inverter while the charger is on).

Having separate chargers and inverters means you can do DC coupling. DC coupling is not as efficient as AC coupling, but it is usually very robust and allows equipment from different manufacturers to be used together.

I'm not sure why you are having problems with the Meanwell charger... I recall that someone else mentioned that it doesn't play nice with other equipment.

In order to play nice, all charging equipment must use the same bulk-absorb-float protocol that is used in most RE systems. Some chargers use the terms 'bulk', and 'absorb' differently... that is they try to maintain constant current during absorb. That type of charging will not work well with typical RE charging in which 'absorb' is defined as a constant voltage.

--vtMaps

lkruper

vtmaps wrote: »

Having separate chargers and inverters means you can do DC coupling. DC coupling is not as efficient as AC coupling, but it is usually very robust and allows equipment from different manufacturers to be used together.

I'm not sure why you are having problems with the Meanwell charger... I recall that someone else mentioned that it doesn't play nice with other equipment.

In order to play nice, all charging equipment must use the same bulk-absorb-float protocol that is used in most RE systems. Some chargers use the terms 'bulk', and 'absorb' differently... that is they try to maintain constant current during absorb. That type of charging will not work well with typical RE charging in which 'absorb' is defined as a constant voltage.

--vtMaps

Does RE charging mean a daily discharge/charge cycle as opposed to a UPS style backup used infrequently? Would RE charging be three-stage as opposed to UPS style maintenance mode?

vtmaps

lkruper wrote: »

Does RE charging mean a daily discharge/charge cycle as opposed to a UPS style backup used infrequently? Would RE charging be three-stage as opposed to UPS style maintenance mode?

RE charging is what is known as "IUoU". There are many other types of charging.

Here's a good link to get you started: http://forum.solar-electric.com/foru...re-we-missing=

In the above link, check out the posts by StephenDv (post #11 and #13)

--vtMaps

lkruper

vtmaps wrote: »

RE charging is what is known as "IUoU". There are many other types of charging.

Here's a good link to get you started: http://forum.solar-electric.com/foru...re-we-missing=

In the above link, check out the posts by StephenDv (post #11 and #13)

--vtMaps

Thanks, that looks very interesting. Of these types, which one would be the typical three-stage charger? Is there such a thing?

inetdog

lkruper wrote: »

Thanks, that looks very interesting. Of these types, which one would be the typical three-stage charger? Is there such a thing?

The typical three stage charger for RE use has the following characteristics:
Bulk stage is current limited, with a voltage set point which will terminate Bulk. The voltage is not regulated during Bulk.

Absorb stage is a set voltage, but the overall current limit applicable to Bulk will still be in effect. If the voltage drops low enough the CC may shift back to Bulk. The end of Absorb cannot be voltage based, so it will be terminated either by a timer (which may vary with the length of the previous Bulk as well as other factors) or a decrease in current to the chosen End Amps level. If you do not have a shunt, the End Amps value will be confused by any loads that are taken from the battery at the same time it is charging. Different CCs support different Absorb end conditions.

Float is a maintenance voltage, with no current limit other than the one set for Bulk and with a variety of conditions that may take the CC back into either Bulk or Absorb. These include a terminal voltage drop and a high current draw.

Now if you mean what string of letters describes this, I will leave that as an exercise for you.

kaipo_boy

mike95490 wrote: »

How many watts can a "stand alone" charger provide to your batteries ? Less than 2,000 watts usually, since that's often the limit of a household circuit. The integrated chargers in an inverter can usually supply several times that amount. That's a Big Deal to reduce charging of a large battery bank

My 48V 15A IOTA = 800w ( with a 20A 120V plug on it's power cord)
My 48V inverter charger on a 10KW generator, 100A (4,000w)

So far, this is the only convincing argument I've heard. So why do lots of people have them? Cachet? Easy of use? or to enjoy heavy charging if needed?
I thought there was a 'sweet spot' at the C10 rate that batteries liked to be charged at... to go heavier was not recommended? or is that hogwash? Since my system can make about 29amps on a sunny day (just), I thought it was perfect for the Kid and its 30amp max... with the battery bank at 208ah, at the usual low-mid 20 amp range it was right bang on at the C10 rate...
Mike, don't you have Ni-Fe? which might not mind heavier amps charging...

mike95490

kaipo_boy wrote: »

So far, this is the only convincing argument I've heard. So why do lots of people have them? Cachet? Easy of use? or to enjoy heavy charging if needed?
I thought there was a 'sweet spot' at the C10 rate that batteries liked to be charged at... to go heavier was not recommended? or is that hogwash? Since my system can make about 29amps on a sunny day (just), I thought it was perfect for the Kid and its 30amp max... with the battery bank at 208ah, at the usual low-mid 20 amp range it was right bang on at the C10 rate...
Mike, don't you have Ni-Fe? which might not mind heavier amps charging...

Yep, mostly, lead acid batteries can be charged pretty hard till they reach 80% of full. (BULK) The battery is pretty efficient and does not heat up much, so folks with a 600ah battery bank, could easily feed it 60 amps, with no issues Getting 60amps from a plug in charger, for a long period of time (15 minutes or more) is not going to happen 60A @ 24V, and 80% eff will pull 1,728 watts, which is a full 15 amps Mostly, outlets don't like that and will heat up on you. But if your 48V bank needs a quick charge, standalone chargers are generally going to be pretty small

Mountain Don

One thing I like about the inverter charger units from Outback and Xantrex has been that they ramp up the battery charger amps rather than slam on full rate charge like the Iota do. That and the ability to program the maximum amps into the battery. (Mostly familiar with Outback VFX series).

vtmaps

Mountain Don wrote: »

One thing I like about the inverter charger units from Outback and Xantrex has been that they ramp up the battery charger amps rather than slam on full rate charge like the Iota do. That and the ability to program the maximum amps into the battery. (Mostly familiar with Outback VFX series).

It's even better than that... the Outbacks, although not PF corrected, have a very good PF (assuming they are provided with a clean sine wave). The Iota has a very poor PF and an enormous startup surge... not a problem on the grid, but causes much grief to those with generators.

Also, the Outbacks can be configured to protect the generator from overload... I have my Outback set to draw no more than 12 AC amps from my generator. It will use the full 12 amps while charging, but if I pull the trigger on my circular saw the Outback will instantaneously stop charging the battery so the generator's output goes to the saw. When I turn off the saw, the Outback begins charging again. With smaller loads (washing machine) the Outback will divide the load between the washer and charging, so as not to exceed 12 AC amps from the generator.

--vtMaps

Belmont Solar

There's nothing like an Outback inverter/charger for reliability, keeping the batteries healthy etc.
We do have a few installations that have a setup such as your's with a separate charger due to upfront cost, but they often are not satisfactory in the long term and they end up upgrading to the inverter/charger

zoneblue

I'll second the sticker shock of a proper UL listed for hardwire inverter (almost all come with charger functionaliy). I tried to avoid it too, but finally at inverter number 3, ended up with the vfx, what i should have done at the outset. And we dont even use the charger!

kaipo_boy

zoneblue wrote: »

I'll second the sticker shock of a proper UL listed for hardwire inverter (almost all come with charger functionaliy). I tried to avoid it too, but finally at inverter number 3, ended up with the vfx, what i should have done at the outset. And we dont even use the charger!

Zoneblue, can you say which 3 inverters you had which failed? were the failures simply hardware/normal use related or were there extenuating circumstances (bugs, dropping out a plane at altitude, death by .45 cal, you know... the usual and, were you able to make any sort of warranty claims? how long did they last?

2manytoyz

My coworker's Xantrex Prosine 3.0 is toast. The downside is when one feature fails, the other can too. He can neither produce AC power, or charge his batteries with it.

I went with a cheap setup, using a basic Xantrex sine wave inverter, and a separate Iota 75A charger. All these components have worked flawlessly so far. If the charger fails, I can use the 55A Iota from the camper. If one inverter fails, I already have another hardwired. Only takes moments to move the loads.

If I had the money up front, I would like to have purchased an Outback setup. It has the ability to adjust many parameters that I cannot with my setup. But I have no regrets. The hardware all works as advertised, though I have more bits and pieces to do what the all inclusive systems already have in one nice package.

zoneblue

#1 i was new to the industry, and trusting the seller of a 4kW (wow) 'pure' sine inverter. It had all the right specs but was made in china with no real branding. Readily available locally online etc. A friend said they were ok. Got it, lasted exactly 7 days then went pop. Read up about them, people imported container lots of the things, and fully 20% failed within one week. No quality control. Got wise sent that sucker back and demanded a full refund.

#2. As we had just bought the place, didnt have the funds to buy a UL listed inverter, (thats how we arrived at #1) so another friend loaned us a 1kW inverter. We had the thing for long enough that we ended up buying it off him, despite that it wasnt the size we wanted. And it cost an arm and a leg, being european. The thing worked well, but wasnt big enough for some of our loads.

#3 3W vfx. finally. woud have been cheaper to started here, but you live and you learn. We actually got the thing reasonably cheap in the end by importing it ourselves.

The money buys you the quality assurance of the brand, and the UL listing, which lets me sleep at night.
Tares still a little high. But i prefer LF inverters with some weight to them. Call me old fashioned. There are some ok non listed HF mid tier inverters, Samlex, Cotek, Xantrex, Excel etc. These appear to serve ok, you just need to do your homework.

kaipo_boy wrote: »

Zoneblue, can you say which 3 inverters you had which failed? were the failures simply hardware/normal use related or were there extenuating circumstances (bugs, dropping out a plane at altitude, death by .45 cal, you know... the usual and, were you able to make any sort of warranty claims? how long did they last?

Lake_Man

vtmaps wrote: »

Having separate chargers and inverters means you can do DC coupling. DC coupling is not as efficient as AC coupling, but it is usually very robust and allows equipment from different manufacturers to be used together.

--vtMaps

What is DC coupling ?

I also would prefer to have a separate charger and inverter. I currently have a Victron 5000 VA Quattro and am happy with it. However the disadvantage i see is that when mains power is UP, then the grid power passes straight through the inverter to the loads. Not ideal where i live with the grid being as it is where we are.

So to split the system out to a charger seems a better way to go. When the grid is UP the charger is on and supplies current to the batteries. The batteries are in turn connected to an Inverter system. The end loads never "see" the grid - only ever get clean sine wave from the inverter. All the dirty grid issues never get past the DC battery bank. I think the only issue is protecting the charger from voltage surges?

What are the pros and cons to this approach?

inetdog

That is essentially how a dual conversion UPS works, so the pros and cons would be very similar.
Biggest pro is zero time, zero glitch transfer from grid power to battery power when necessary.

vtmaps

Lake_Man wrote: »

What is DC coupling ?

DC coupling means that you have several sources of DC power such as solar, wind, hydro, generator, or grid, and that all the DC power goes to a battery. The loads (a DC load and/or an AC load via an inverter) are also connected to the battery.

If you do DC coupling, it is usually necessary that all charging sources use the same RE charging protocol.

--vtMaps

Lake_Man

vtmaps wrote: »

t all charging sources use the same RE charging protocol.

--vtMaps

OK so what does "all use the same RE charging protocol" mean ?

vtmaps

Lake_Man wrote: »

OK so what does "all use the same RE charging protocol" mean ?

Go back to post #6 in this thread and follow the link. In brief, an RE charging protocol is the familiar bulk-absorb-float that most RE (renewable energy) equipment uses.

--vtMaps