Xantrex6048 and 8 230ah 6v batterys and 4 12v deka marine batterys 187ah

islandboy43444

I am using XANTREX6048 AND 8 230AH 6V BATTERYS AND 4 12V DEKA MARINE BATTERYS 187AH with 12 sun 285w panels with a flex80 charge controller, the system was installed about a week and it worked ok until now its like the batteries are not being charged because i loose power before a few hours and it wasnt this was when in the beginning I need help please

Cariboocoot

Re: Xantrex6048 and 8 230ah 6v batterys and 4 12v deka marine batterys 187ah

Welcome to the forum.

Let's do a little analysis and see what is wrong.

For one thing, you've got mixed type and size batteries: one string @ 230 Amp hours and one string @ 187 Amp hours. The capacity difference here is over 20%. This means you can't properly charge the 230's without over charging the 187's and if you set the parameters for those the others would be undercharged. They don't really add up to 417 Amp hours. Xantrex recommends 600+ Amp hours for the XW 6048, btw.

You've got a 3420 Watt array which ought to provide 54 Amps peak current, which should charge the batteries. Even if you get the right battery bank it will work. But you need to check the Absorb time settings to make sure it stays at the right Voltage for long enough.

The other question is how much power is being used. Even mismatched batteries would be able to supply some power. Based on minimizing the bank: about 8 kW hours worth. If you're using less than that then there is definitely some deficit charging problem (incorrect Absorb Voltage and/or time).

Can you provide details about the charging parameters?
Have you taken specific gravity readings of the battery cells?
Can you get the XW to charge from generator input?

islandboy43444

Re: Xantrex6048 and 8 230ah 6v batterys and 4 12v deka marine batterys 187ah

Thanks for the response i am new to this what should the absorb time and voltage be set at and i did try from a generator the honda 4500kw and it didnt work so for on the flex80 its saying i have used 18kwh and on the 6048 it maximum read that i have seen is 2.72 it usually sits around .68 -.98 on the display

Cariboocoot wrote: »

Welcome to the forum.

Let's do a little analysis and see what is wrong.

For one thing, you've got mixed type and size batteries: one string @ 230 Amp hours and one string @ 187 Amp hours. The capacity difference here is over 20%. This means you can't properly charge the 230's without over charging the 187's and if you set the parameters for those the others would be undercharged. They don't really add up to 417 Amp hours. Xantrex recommends 600+ Amp hours for the XW 6048, btw.

You've got a 3420 Watt array which ought to provide 54 Amps peak current, which should charge the batteries. Even if you get the right battery bank it will work. But you need to check the Absorb time settings to make sure it stays at the right Voltage for long enough.

The other question is how much power is being used. Even mismatched batteries would be able to supply some power. Based on minimizing the bank: about 8 kW hours worth. If you're using less than that then there is definitely some deficit charging problem (incorrect Absorb Voltage and/or time).

Can you provide details about the charging parameters?
Have you taken specific gravity readings of the battery cells?
Can you get the XW to charge from generator input?

Cariboocoot

Re: Xantrex6048 and 8 230ah 6v batterys and 4 12v deka marine batterys 187ah

islandboy43444 wrote: »

Thanks for the response i am new to this what should the absorb time and voltage be set at and i did try from a generator the honda 4500kw and it didnt work so for on the flex80 its saying i have used 18kwh and on the 6048 it maximum read that i have seen is 2.72 it usually sits around .68 -.98 on the display

To charge using the XW you need to program it too. That is an adventure in masochism and I believe you need the System Control Panel http://www.solar-electric.com/xaxwsycopas.html to do it properly.

Your FM80 will report the kW hours it has delivered to the batteries, but not the kW hours your system has used. These can be two quite different numbers.

I do not know which numbers from the XW you are reporting. It could be kW hours or it could be Watts at the moment. I will say here and now that I am not a Xantrex man, having been completely disillusioned with their products and service, so I am not familiar with the nuances of the machines.

Fortunately we have several people on the forum who have the necessary masochistic tendencies to put up with XW equipment who have learned how to make it function.

You should have a manual for the thing. If you can decipher it, it will tell you how to set various charging parameters such as Absorb Voltage (which I believe they call "Bulk Voltage") and Absorb time limit as well as generator input parameters for Voltage and current.

But I can at least help you with the parameters on the FM80. Again you need the manual to find where in the menus the various items are set. You should have Absorb Voltage at 59.2 and maximum Absorb time set to 4 hours to begin with. Float Voltage should be set at 55.2 to start. Do you ever see the word "Float" come up on the display? That is a big clue.

If you are seeing 18 kW hours output from the FM80 you are using at least that much power, and it's quite a lot. For your 3420 Watt array to produce that much you must be getting over 5 hours of good sun. The trouble would be if you are using even more than that: the batteries end up supplying the balance and that means deficit charging; more kW hours goes out of the batteries in a day than the panels put back in.

At this point it looks as though the basic problem is an undersized and mismatched battery bank.

islandboy43444

Re: Xantrex6048 and 8 230ah 6v batterys and 4 12v deka marine batterys 187ah

I am in the bahamas we have plenty of sun atleast 10hrs per day,i have the remote controll panel and yes i have seen float on the fm80 i currently do not have those settings it has default settings in it will adjust and monitor it.

Cariboocoot

Re: Xantrex6048 and 8 230ah 6v batterys and 4 12v deka marine batterys 187ah

Just to note that 10 hours of sun a day does not mean 10 hours of sun on the panels or 10 hours of "equivalent good sun". We get 16 hour days here in Summer, but the panel exposure is still limited by the angle as the sun "moves through the sky", and early/late sun has to travel through more atmosphere.

You're still better off than we are, though, because we get the opposite in Winter: 6 hour days with about 2 hours equivalent good sun.

Your hotter temperatures won't be doing you any good; drops panel Voltage and stresses batteries. It is important to have a remote temperature sensor on your FM80 to compensate for high battery temp. Otherwise they could get too much Voltage when hot and lose more water.

YehoshuaAgapao

Re: Xantrex6048 and 8 230ah 6v batterys and 4 12v deka marine batterys 187ah

You do need the system control panel to program a XW inverter to charge off of grid or generator on anything other than default flooded battery settings.

The Display on the XW inverter is output. When charging it is amps going to battery, when inverting or selling/loadshaving/gridsupporting, is KW of AC output. When it is doing neither (passthrough), it displays '---'

Xantrex XW inverters will not talk to non-Xantrex charge controllers over the XANBUS network (Outback speaks a more standardized MODBUS; XANBUS is proprietary) so you will always operate on max duration absorption charge cycles on the FM80 if the inverter is doing any work so it will be important to set a reasonable absorb time on the charge controller.

XW6048's sweetspot for inverting efficiency is 1500-2000 watts with an extended sweetspot between 1000 and 2500 watts. Below 1000 watts, efficiency drops quickly. For charging the efficiency sweet spot is 40A but power factor (important on generators) is highest at 50A so that balances out to 45A. With my system 50A charge current plus house loads keeps the generator working near-max.

My house loads runs 0.7-1.3 in winter morning, 1.0-1.5 summer morning, 1.5-2.0 winter evening, and 1.5-2.5 in summer evening. It is a subpanel that doesn't cover the whole house since I am grid tied - it has all 120V circuits not in the kitchen (does have fridge) or laundry. My battery bank is not large enough to handle these loads indefinitely off-grid so I have circuit breakers labeled for short-term (a few hours - 1 hr thunderstorm outage or 2-6 hr daytime rolling blackouts, open circuit breaker at utility; patio, garage), long-term outage / generator-assisted off-grid (a couple days - weather disaster, blown substation transformer, cascading regional power failure; living room / no stereo, family room, bedrooms), and indefinite outage / battery-only off-grid (week or longer - EMP from coronal mass ejection, war, non-SHTF martial law; fridge + chest freezer + swamp coolers + SHW pumps)

islandboy43444

Re: Xantrex6048 and 8 230ah 6v batterys and 4 12v deka marine batterys 187ah

Thanks for the info and advice,what the largest load you can run on 3 xw 6048 in parallel with 32 batterys

YehoshuaAgapao wrote: »

You do need the system control panel to program a XW inverter to charge off of grid or generator on anything other than default flooded battery settings.

The Display on the XW inverter is output. When charging it is amps going to battery, when inverting or selling/loadshaving/gridsupporting, is KW of AC output. When it is doing neither (passthrough), it displays '---'

Xantrex XW inverters will not talk to non-Xantrex charge controllers over the XANBUS network (Outback speaks a more standardized MODBUS; XANBUS is proprietary) so you will always operate on max duration absorption charge cycles on the FM80 if the inverter is doing any work so it will be important to set a reasonable absorb time on the charge controller.

XW6048's sweetspot for inverting efficiency is 1500-2000 watts with an extended sweetspot between 1000 and 2500 watts. Below 1000 watts, efficiency drops quickly. For charging the efficiency sweet spot is 40A but power factor (important on generators) is highest at 50A so that balances out to 45A. With my system 50A charge current plus house loads keeps the generator working near-max.

My house loads runs 0.7-1.3 in winter morning, 1.0-1.5 summer morning, 1.5-2.0 winter evening, and 1.5-2.5 in summer evening. It is a subpanel that doesn't cover the whole house since I am grid tied - it has all 120V circuits not in the kitchen (does have fridge) or laundry. My battery bank is not large enough to handle these loads indefinitely off-grid so I have circuit breakers labeled for short-term (a few hours - 1 hr thunderstorm outage or 2-6 hr daytime rolling blackouts, open circuit breaker at utility; patio, garage), long-term outage / generator-assisted off-grid (a couple days - weather disaster, blown substation transformer, cascading regional power failure; living room / no stereo, family room, bedrooms), and indefinite outage / battery-only off-grid (week or longer - EMP from coronal mass ejection, war, non-SHTF martial law; fridge + chest freezer + swamp coolers + SHW pumps)

Cariboocoot

Re: Xantrex6048 and 8 230ah 6v batterys and 4 12v deka marine batterys 187ah

islandboy43444 wrote: »

Thanks for the info and advice,what the largest load you can run on 3 xw 6048 in parallel with 32 batterys

Well ... three XW 6048's can supply 18 kW of power. But "32 batteries" is subjective; they'd have to be quite large batteries to sustain that amount of power for any significant amount of time.

For example Xantrex recommends a minimum of 600 Amp hours on the 6048 (mostly for filtering reasons but we have to start somewhere). That's 300 * 48 = 14 kW hours. If you had three such banks it would be 42 kW hours which the 18 kW load would drain in about 2 hours. The 375 Amps that such a load would draw would also "flatten" the bank fairly easily as it is about 20% of capacity - twice the 'normal' maximum draw one would expect to use.

So you see you have two things to consider when supply large loads: enough Amp hour capacity to supply the power over time and enough Amp hour capacity to handle the maximum current draw at the moment without suffering too much Voltage drop.

Tricky stuff.

YehoshuaAgapao

Re: Xantrex6048 and 8 230ah 6v batterys and 4 12v deka marine batterys 187ah

Worse, XW6048 can surge to double its capacity for 10-15 seconds, so it can load a whopping 750 amps (820 at 44V) on them batteries if you are say starting some monster 3-phase motor. You should plan on half the inverter's capacity for continuous usage and battery sizing while sizing your wire for full capacity continuous. So 3 inverters (18000W) / 44 volts (lowest LBCO; 100% DOD; 1.75V per cell) is 410 amps. You would want at least 10 times that in amp hours. 4100 amp hours (Yes my battery bank is undersized to this standard but I am grid-tied/bi-modal and using batteries for backup power and load shaving).

The wire would need to be sized for 410 amps continuous - 700KCMil (900KCMil derated for 105-113F) over one set of wires 4/0 (250KCMil derated for 105-113F) over two sets of wires. If you plan on using inverter surge capacity, you would need to increase wire size accordingly - 410 continuous plus 410 more amps noncontinuous - 600KCMil over two cable sets (700KCMil derated) or 300KCMil (350KCMil derated) over three cable sets.

Looks like the highest capacity you can get in a single string is 2400 amp hours (Surrete 2 YS 31P - 2V, 24 batteries for a 48 volt string). Get 2 strings of those, 4800 amp hours. You would need at least 11.5KW (5% AH rating @ 48V) of solar to charge all these up. Especially if you are grid tied, it would be better to max out the inverter and then some (capacity is AC, not DC) so 20-21KW of solar which is just under C/10.

Powering a whole house off-grid (or bi-modal) is very expensive. And the last guy on the forum that tried to do that with 4 XW6048 inverters had a clueless installer (3 inverters are more complex - external bypass requried; 4 inverters are lots more complex - 2 subpanels, 2 PDPs) and probably wasted all his money especially on the battery bank that was getting bare minimum maint charging at best with the system not up and running for so long.

Cariboocoot

Re: Xantrex6048 and 8 230ah 6v batterys and 4 12v deka marine batterys 187ah

The 10-15 second surge load usually isn't a problem because wiring is rated for continuous current and a momentary jump above that can be handled. Likewise batteries can usually take a momentary "hit" (especially AGM's) but not sustained high current.

We may oversimplify things when explaining how to get a system up and running but on the other hand if we went into every detail every time and put in all the fine math - our host NAWS would have to buy 10X the server space to hold all the additional info, and our fingers would drop off from all the typing.

NorthGuy

Re: Xantrex6048 and 8 230ah 6v batterys and 4 12v deka marine batterys 187ah

YehoshuaAgapao wrote: »

The wire would need to be sized for 410 amps continuous.

Each inverter gets its own set of wires, so you woudn't need a single wire carrying 410A.

islandboy43444

Re: Xantrex6048 and 8 230ah 6v batterys and 4 12v deka marine batterys 187ah

K thanks would a three phase 20k generator being tied in to charge the battery make it any more easier and stable

inetdog

Re: Xantrex6048 and 8 230ah 6v batterys and 4 12v deka marine batterys 187ah

Cariboocoot wrote: »

We may oversimplify things when explaining how to get a system up and running but on the other hand if we went into every detail every time and put in all the fine math - our host NAWS would have to buy 10X the server space to hold all the additional info, and our fingers would drop off from all the typing.

And fewer people would start reading the threads! Got to get them hooked first....

BB.

Re: Xantrex6048 and 8 230ah 6v batterys and 4 12v deka marine batterys 187ah

islandboy43444 wrote: »

K thanks would a three phase 20k generator being tied in to charge the battery make it any more easier and stable

Probably will make the problem more complex... We have this poster that is struggling with a 3 phase install with what is really a single phase installation:

Is the system set up right

All things being equal (which they rarely are), single phase is probably a lot simpler.

-Bill

Cariboocoot

Re: Xantrex6048 and 8 230ah 6v batterys and 4 12v deka marine batterys 187ah

Really you can only use a 3 phase generator on a 3 phase system.
Unless you like endless headaches. :roll:

YehoshuaAgapao

Re: Xantrex6048 and 8 230ah 6v batterys and 4 12v deka marine batterys 187ah

NorthGuy wrote: »

Each inverter gets its own set of wires, so you woudn't need a single wire carrying 410A.

In the Xantrex PDP the inverter is wired to the DC busbars in the PDP. The batteries connect to the DC busbars separately - someone could easily run only a single set of cables from the PDP to a multi-string battery bank.

Cariboocoot

Re: Xantrex6048 and 8 230ah 6v batterys and 4 12v deka marine batterys 187ah

YehoshuaAgapao wrote: »

In the Xantrex PDP the inverter is wired to the DC busbars in the PDP. The batteries connect to the DC busbars separately - someone could easily run only a single set of cables from the PDP to a multi-string battery bank.

This is where you'd run into trouble as you aren't going to find a single wires capable of handling over 300 Amps. Curiously, to get three stacked inverters to function together correctly the DC has to be tied. The best way to do this, I think, would be to wire each inverter to some very large bus bars and have three separate battery banks wired to those same bars. That way each battery bank would feed the bars (through a fuse) and each inverter would draw (or feed when charging) from those bars (through a fuse).

Wiring gets complex when you enter the realm of heavy current. You can parallel large conductors by code, but each one still needs to be protected individually in case another fails. Sometimes the off-the-shelf wiring equipment can not accommodate the needs and some custom fabrication is necessary.

YehoshuaAgapao

Re: Xantrex6048 and 8 230ah 6v batterys and 4 12v deka marine batterys 187ah

Cariboocoot wrote: »

This is where you'd run into trouble as you aren't going to find a single wires capable of handling over 300 Amps. Curiously, to get three stacked inverters to function together correctly the DC has to be tied. The best way to do this, I think, would be to wire each inverter to some very large bus bars and have three separate battery banks wired to those same bars. That way each battery bank would feed the bars (through a fuse) and each inverter would draw (or feed when charging) from those bars (through a fuse).

Wiring gets complex when you enter the realm of heavy current. You can parallel large conductors by code, but each one still needs to be protected individually in case another fails. Sometimes the off-the-shelf wiring equipment can not accommodate the needs and some custom fabrication is necessary.

Still have the issue of coming up with the connectors for the ends and attaching them, but Wire and Cable to Go sells up to 1000 KCMIL THHN. They also have XLP/USE-2/RHH/RHW-2 up to 750 MCM (costs 50% more). They are cheaper than home depot (if buying enough for free shipping, $1000 currently I think) but more expensive than contractor pricing at a electric supply shop. Probably only going to find pre-connectored wire at 2/0 or 4/0.

Xantrex PDP has each inverter going through a 250A breaker (12KW @ 48V), but the battery strings reach the busbar without any fuses or breakers because I'm using the PDP's busbar as the parallelling busbars. James probably would only fuse each battery string separately through a dedicated fuse or breaker box, and he would want the battery busbars in a box too. The fusing would add several hundred bucks to cost (big current is expensive). The PDP has 250A breaker for each inverter in the PDP I think that would satisfy the protection requirement (but all battery DC is pooled prior to any over-current protection). The DC Postive busbar has 4 screws for wiring from the charge controlers (after 80A breaker), 3 lug holes for 250A inverter breakers, and 2 lug holes for battery cable (no breaker or fuse). I've found it costs less to follow directions.

NorthGuy

Re: Xantrex6048 and 8 230ah 6v batterys and 4 12v deka marine batterys 187ah

YehoshuaAgapao wrote: »

James probably would only fuse each battery string separately through a dedicated fuse or breaker box.

I would too. I would use a breaker or a disconnect on each string so that I could disconnect one string without disconnecting inverter. This way I could take one string off for maintenance without interrupting power to the house.

YehoshuaAgapao

Re: Xantrex6048 and 8 230ah 6v batterys and 4 12v deka marine batterys 187ah

NorthGuy wrote: »

I would too. I would use a breaker or a disconnect on each string so that I could disconnect one string without disconnecting inverter. This way I could take one string off for maintenance without interrupting power to the house.

Makes sense off-grid. No grid to take advantage of. Bi-modal you can just flip the bypass breaker and shut off all the other breakers and the DC busbar will have no juice on it (I did that when replacing the standard washers with stainless steel washers - standard washers corroded white within weeks; stainless shows no sign of corrosion after 3.5 months). Battery terminals and cables are still hot but probably can't avoid that. Best to do that at night though. Battery cable disconnect/breakers would allow it to be done during the day without losing production, disconnecting only the string being worked on at the moment.