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Schneider Conext XW Pro 6848

etanstaafl

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I am fairly new & considering using the Schneider Conext XW Pro 6848 to build upon. A simple & complex question, will the XW Pro sync / combine power from different inputs to feed a high start up or short term requirement. Example PV out put or generator will run the load of the house (including AC run) however when the AC starts will need added power from the batteries.

Also are there other options to control & sync four power inputs, Grid, PV, Generator, & battery?
 
The XW Pro 6848 does not have a built in solar charge controller only an AC charger. Solar charge controllers are separate items that connect to the batteries (or battery bus bar) directly so the inverter output is limited to what the inverter and/or batteries can supply. In this case its well in excess of the 6800 Watt rating.
If there is an AC source, either grid on AC input 1 or generator on AC input 2 then there is a possibility of sharing the load between the 2 sources.
The Grid input (AC 1) has a Peak Load Shave feature where you can set the amperage value for the AC input 1 between 0A up to the size of the breaker feeding AC 1. I've never tried it but if the amp value was set to 60A (limit of the internal transfer switch) then the inverter would kick in to help run the load if AC 1 maxed out. Wow, that would be a lot of power!! SEE EDIT below.
Likewise AC 2 has a setting called Gen Support where an amperage value could be set such that the inverter would start up and help supply the load if AC 2 maxed out at whatever value you selected based on the size of the generator.

EDIT: After reviewing the Installation Guide for XW+, which is the older model, it does specify the output breaker should be limited to 60A. Also the mechanical lugs are limited to #4 wire I believe. Based on the above, the peak load shave feature should not set so high that the combined AC input plus the maximum output of the inverter would exceed 60A when sharing a load.
 
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The XW Pro 6848 does not have a built in solar charge controller only an AC charger. Solar charge controllers are separate items that connect to the batteries (or battery bus bar) directly so the inverter output is limited to what the inverter and/or batteries can supply. In this case its well in excess of the 6800 Watt rating.
If there is an AC source, either grid on AC input 1 or generator on AC input 2 then there is a possibility of sharing the load between the 2 sources.
The Grid input (AC 1) has a Peak Load Shave feature where you can set the amperage value for the AC input 1 between 0A up to the size of the breaker feeding AC 1. I've never tried it but if the amp value was set to 60A (limit of the internal transfer switch) then the inverter would kick in to help run the load if AC 1 maxed out. Wow, that would be a lot of power!! SEE EDIT below.
Likewise AC 2 has a setting called Gen Support where an amperage value could be set such that the inverter would start up and help supply the load if AC 2 maxed out at whatever value you selected based on the size of the generator.

EDIT: After reviewing the Installation Guide for XW+, which is the older model, it does specify the output breaker should be limited to 60A. Also the mechanical lugs are limited to #4 wire I believe. Based on the above, the peak load shave feature should not set so high that the combined AC input plus the maximum output of the inverter would exceed 60A when sharing a load.
Great reply & thanks, This brings up a few other issues. Solar will be a second step but soon after. Need to deal with a roof issue & breakout the chainsaw & drop a few more trees. Just been watching PG&E to see how much they do as part of line maintenance.

I will have to go back to understand how the house will be fed by PV first then Grid. If Grid is down roll to generator & battery during sleep time. Battery also to bridge power shortage (short term / well pump & AC startup). With the XW Pro limied to 60a internal breakers & the main 200a will need to better understand how to manage. Today I only have the needed breakers on when on generator.

The weatherhead is on an out building (200a with well pumps) and the best roof for solar panels. Sub panel with AC in the main house. 100a

Am a bit dyslexic so hope this make sense.
Thanks again
 
I will have to go back to understand how the house will be fed by PV first then Grid.
The XW Pro has a large user set up menu with lots of options. I'm sure if you are reading the operating manual its a bit overwhelming the first time, I thought so anyway.
If you want PV priority you would use the Peak Load Shave feature but set Amps to 0. Then using the peak load shave timers you could set the start/stop times for daylight hours only or set peak load shave to operate 24/7 which would mean at night the load would be carried by the batteries. This type of usage would be termed self-consumption. If the batteries reach their low voltage set point the inverter automatically exits peak load shave and reverts back to the grid or generator. I believe you can select AC1 or AC2 priority in the menu. The problem with this would be you are then not sharing the load (grid amps set to 0) to help handle those start up surges. Not to worry though.

The solution to high inrush currents on induction motors is by using soft starters on your AC condenser and well pump. they can cut inrush by up to 70%. I'm using a HyperEngineering product on our 4 ton AC unit, works great. The XW+ starts and runs the condenser no problem.

Our house is only 2000 sq ft and we have natural gas for water heating, space heating & stove top so our peak electrical requirements are modest. I am able to back up our whole house in an outage (200A panel) with a single inverter being fed by a 60A breaker. It just requires a little common sense and practicing manual load control as in not turning on the AC, the double electric ovens, toaster oven, microwave, coffee maker and dishwasher all at once.
 
Great info again thanks, looking into the soft start.

1200 sq ft, all propane other then 2 fridges & 1 freezer also the AC, I manually shut off breakers & only use the above ground pump (cheaper to replace I have two water systems) if needed & control what else is running for the few minutes to pressurize the system, again when necessary.

Was hoping to run selected circuits in the house with AC "at times" through the XW inverter, powered by PV or the generator (7000 watt when on propane, hardwired & piped) & have a 3 kw battery bridge the startup. The soft start will be a great help. Usually only need AC from 3 to 7 pm runs a few times.

Also need to calculate if a 3 kw battery will run the house after I shut off the generator until the next AM. Two fridges & 1 freezer, minimal lights & possible the heater kicking on a few times, if the outage starts after I go to sleep & haven't started a fire.

Is this asking too much from the XW inverter?

Thanks
 
Also need to calculate if a 3 kw battery will run the house after I shut off the generator until the next AM.
I believe you mean a 3kWh battery. Probably will not be enough. LFP chemistry has usable power of 80 to 90% of its rated capacity but does slowly decrease with aging and cycling. I would recommend starting with 5 kWh at a minimum but most of the rack mounted or wall mounted batteries that are popular (SOK, EG4, Orient Power) have a built in breaker and/or BMS that limits the discharge current to 100A. Since the XW Pro can surge to over 10kW (200A at 50V) you would need 2 of the batteries mentioned above or one large battery capable of supplying 200A.
Is this asking too much from the XW inverter?
Not at all the Schneider is a beast but you have to match up the components in your system so they all provide the necessary performance while staying within their specified limits. For example LFP batteries generally should not have continuous discharge rates above 1C.
Soft starters are going to be a key device in your system.
 
Truly apprecaite all your guidance. Was raised by an eningeer & taught to do my homework. Also over build a bit. This is the right path starting with the XW & a battery Will adjust to 5k Wh thanks again
 
If you want PV priority you would use the Peak Load Shave feature but set Amps to 0. Then using the peak load shave timers you could set the start/stop times for daylight hours only or set peak load shave to operate 24/7 which would mean at night the load would be carried by the batteries.

@BentleyJ -- Does the XW have the ability to specify daylight or evening hours on those timers, or would it have to be adjusted as the seasons change? I'd like to set up self-consumption in the evening (with a reserve SoC), and then to recharge from the generator input during daylight hours (the generator input would actually be Sunny Islands with AC-coupled solar). But this would be a pain to keep up with as the seasons change...
 
Does the XW have the ability to specify daylight or evening hours on those timers, or would it have to be adjusted as the seasons change? I'd like to set up self-consumption in the evening (with a reserve SoC), and then to recharge from the generator input during daylight hours (the generator input would actually be Sunny Islands with AC-coupled solar). But this would be a pain to keep up with as the seasons change...
I'm using the older model XW+ but I believe this is applicable to the Pro as well. The Peak Load Shave Timers are based on 2 x 24hr clocks. One for start time and one for stop time. So other than having an automatic Daylight Savings time adjustment, it does not have the capability to self adjust based on Sunrise and Sunset like for example a home automation system. Likewise it does not differentiate between weekends, off peak, and weekdays, on peak times.
There is also another problem with regard to Peak Load Shave and automatic recharging. There is a hard coded firmware feature that forces the Schneider to exit Peak Load Shave mode at +0.5V above the recharge voltage setting. This means that an automatic recharge cycle is not triggered so you would have to initiate it manually everyday or set up a PLC on the RS485 comm port. GXMnow and 400bird have posted info on this subject.
 
If there is an AC source, either grid on AC input 1 or generator on AC input 2 then there is a possibility of sharing the load between the 2 sources.
I think you understand, but I'd like to point out for others, the XW will only qualify and connect to a single AC input at a time. It never will connect to both inputs at the same time.

The weatherhead is on an out building (200a with well pumps) and the best roof for solar panels. Sub panel with AC in the main house. 100a
Seems like it would be a good install, if your house would be fine on the 60 amp pass through.
Just replace the 100 amp breaker at the weather head for a 60
Pull that input wiring from the 100 amp panel and install on AC input 1 on the XW.
Install new wire from XW output to sub panel.

Also need to calculate if a 3 kw battery will run the house after I shut off the generator until the next AM. Two fridges & 1 freezer, minimal lights & possible the heater kicking on a few times, if the outage starts after I go to sleep & haven't started a fire.
Doesn't sound like enough battery. I'd recommend an energy audit or monitoring your overnight use. That could be as simple as checking the meter at sunset and sunrise.
Is this asking too much from the XW inverter?

Thanks
My house is 1400 SQ ft, no well pump, single fridge. We run the central AC off the XW. You should be fine, but your actual numbers will be the deciding factor.
The XW can do 6800 watts continuous. 12,000 watts max, the overloaded curve is very generous. 8,500 watts for something like 30 minutes.
My base load overnight is 300-500 watts. It's an easy life for the XW.

I'm using the older model XW+ but I believe this is applicable to the Pro as well. The Peak Load Shave Timers are based on 2 x 24hr clocks. One for start time and one for stop time. So other than having an automatic Daylight Savings time adjustment, it does not have the capability to self adjust based on Sunrise and Sunset like for example a home automation system. Likewise it does not differentiate between weekends, off peak, and weekdays, on peak times.
Same on the XW pro.
But, peak load shave is likely to be a 24/7 concern or based on utility peak rates. So, I'm not sure sunrise actually effects the need.
There is also another problem with regard to Peak Load Shave and automatic recharging. There is a hard coded firmware feature that forces the Schneider to exit Peak Load Shave mode at +0.5V above the recharge voltage setting. This means that an automatic recharge cycle is not triggered so you would have to initiate it manually everyday or set up a PLC on the RS485 comm port. GXMnow and 400bird have posted info on this subject.
This recharge issue, load shave, PLC, etc is only a concern if your solar is AC coupled or you want to charge from the grid.
With DC coupled PV, everything should work normally.

I'd like to set up self-consumption in the evening (with a reserve SoC), and then to recharge from the generator input during daylight hours (the generator input would actually be Sunny Islands with AC-coupled solar). But this would be a pain to keep up with as the seasons change...
AC coupling on the XW leaves lots to be desired if you are on grid. Off grid, it will charge normally and frequency shift to control the PV inverter.

Also, on the XW you don't connect PV to an AC input.

And why are you connecting a battery inverter (Sunny Island) to a different brand battery inverter through the AC? There's a lot of wasted efficiency there. Plus you could just run your loads right from the Sunny Island.


BentleyJ, I quoted you about 1000 times here, mostly to agree or add to what you said. I couldn't figure out how to quote you but address the OP or others. You know this equipment!
 
AC coupling on the XW leaves lots to be desired if you are on grid. Off grid, it will charge normally and frequency shift to control the PV inverter.

Also, on the XW you don't connect PV to an AC input.

And why are you connecting a battery inverter (Sunny Island) to a different brand battery inverter through the AC? There's a lot of wasted efficiency there. Plus you could just run your loads right from the Sunny Island.

I do have a few reasons--one is redundancy. Another is that I have two battery chemistries (and voltages) that I'd like to take advantage of. The AC-coupled solar has to go somewhere. I'd be tapping directly into that, not having Sunny Island convert to DC and back to AC again... Otherwise agreed that'd be wildly inefficient. :LOL:

After weighing my options, I decided to go with a Victron solution. I'm pretty sure I can stand a Multiplus in between my Sunny Island output and the load, and then I'll gain the ability to supplement the output of SI, sacrifice (some) battery charge overnight, and then top off during daytime from AC coupling.

Maybe that would have been achievable with the XW, but this solution is cheaper, has the ability to hook up a 12V LFP (and keep adding to the bank in parallel), and is still a reputable manufacturer with UL cert, albeit not as many as XW.
 
Seems that every month or two when I try tweaking a setting in the xw6848, I end up in trouble. For instance just tried adjusting float voltage setting from 57.75 to 57.5v. (I have 17 cells) System then proceeded to discharge battery bank from 85% to 72% over then next hour. If I rebooted the box it recovered and no issue.
It's like something corrupts internally and a reboot is needed to properly recover.
Anyone else observe this type of behavior ?
 
The only issues I've noticed related to settings not responding is with "No Float" not turning off charging. I have to Disable the charger to terminate. Not a big deal but then when the charger is Enabled later it triggers a full recharge cycle starting with Bulk even if its not needed.
 
Overnight I do manage thru modbus, the charger on/off stuff
There is a setting from bulk, float and no float, in modbus addresses
Seems to work. On my 17 cells, I turn on float at 56.5v, and no float at 57.5v. Now I must say I've never seen an XW that doesn't have more than 1/2 volt battery error. My mppt says 56.5 when the xw says 57.3v. That is overnight when there is NO CURRENT flowing at all.
 
Overnight I do manage thru modbus, the charger on/off stuff
There is a setting from bulk, float and no float, in modbus addresses.
I do have the published modbus maps, I've been researching RS485 modbus communication with the Gateway for exactly that purpose to trigger a weekly Float recharge. It's not a priority and I don't have an electronics or software background so has proven to be kind of difficult. No so much the theory but for some reason Schneider seems to do things the hard way with their particular implementation.
Question if I may: The manual discusses 3 different power inputs to the Gateway. 1) Via the Xanbus cables. 2) Wall plug-in external power adapter. 3) 24V input on the same screw terminal as RS485 lands. The manual says any of them individually or all 3 can be used but doesn't describe how or if there is priority of one source over the other. In any case, is it necessary to use the 24V input on the screw terminal to power the modbus feature? I'm asking because when I tried to use a RS485 to USB adapter the LED on the Gateway doesn't light up and there is no response from the Gateway even though the adapter is sending a query.
Now I must say I've never seen an XW that doesn't have more than 1/2 volt battery error. My mppt says 56.5 when the xw says 57.3v. That is overnight when there is NO CURRENT flowing at all.
I've compared the XW+ voltage with the BMS values from 2 different batteries and the active balancer. All agree within 0.2V or less depending on resting, charging or Discharging. So complaints here.
 
Have you tried Modbus TCP? That's what I am using successfully.

I can't find it now, but I remember reading that Modbus RS485 hardware was present but the software wasn't implemented, I could be incorrect on that.
 
I do have the published modbus maps, I've been researching RS485 modbus communication with the Gateway for exactly that purpose to trigger a weekly Float recharge. It's not a priority and I don't have an electronics or software background so has proven to be kind of difficult. No so much the theory but for some reason Schneider seems to do things the hard way with their particular implementation.
Question if I may: The manual discusses 3 different power inputs to the Gateway. 1) Via the Xanbus cables. 2) Wall plug-in external power adapter. 3) 24V input on the same screw terminal as RS485 lands. The manual says any of them individually or all 3 can be used but doesn't describe how or if there is priority of one source over the other. In any case, is it necessary to use the 24V input on the screw terminal to power the modbus feature? I'm asking because when I tried to use a RS485 to USB adapter the LED on the Gateway doesn't light up and there is no response from the Gateway even though the adapter is sending a query.

I've compared the XW+ voltage with the BMS values from 2 different batteries and the active balancer. All agree within 0.2V or less depending on resting, charging or Discharging. So complaints here.
I just use the power coming in the Xanbus path. That will die if you lose power on the XW though. The round power cable can be powered from 12v easily and that will always be there even if XW is powered off.
 
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