CONEXT SW 4048 - Possible to use this with the grid?

[Anit767]

The website claims this can be used as a hybrid inverter and tie to the grid. What else would I need to make this setup work? Also, is this inverter battery agnostic? So to recap…

1. I want to be able to reduce energy usage from the grid and prioritize solar. Will I need a grid tie pv inverter? Will any brand work? For example can I use a Sunny Boy?
2. I want to charge the batteries with solar when there’s extra unused energy,
3. I want to use diy lifepo4, not proprietary overpriced batteries.
4. Bonus - grid agnostic - auto switch to off grid when power goes out.
5. I don’t need to sell power back to the grid.

 

[Anit767]

From the Schneider website

Flexible

• Available in 24VDC and 48VDC models. All models support both 50Hz and 60Hz output
• Supports AC coupled and DC coupled off-grid and grid-tie architectures
• Intelligent functionality enables self consumption with solar prioritization, peak shaving and, assisting small generators with heavy loads

 

[MrM1]

Sorry u got no response. Are you still looking at this setup? I have the SW4024 inverter and can answer any of your questions.

 

[MrM1]

Never mind. See u went SMA.

 

[Wolfpv]

Sorry u got no response. Are you still looking at this setup? I have the SW4024 inverter and can answer any of your questions.

Hi - perhaps I should start a new topic - but I'll try this for now. I have a grid-tied system with Enphase M215 micro-inverters. I want to set up a relatively inexpensive battery backup with two 48V x 100A rack batteries. In order to tie to my household wiring I'd need both phases of 240V, and the SW4024 seems to be the only reasonably priced inverter I can find which meets UL1741, and does two-phase. The vendor says it can't work in a grid-tie environment, but the literature says it can. Have you any sage advice? Also, do I absolutely need the battery controller and the battery monitor and the Distribution Panel (and the smart home controller) - the vendor says the system won't work without these.

 

[timselectric]

Hi - perhaps I should start a new topic - but I'll try this for now. I have a grid-tied system with Enphase M215 micro-inverters. I want to set up a relatively inexpensive battery backup with two 48V x 100A rack batteries. In order to tie to my household wiring I'd need both phases of 240V, and the SW4024 seems to be the only reasonably priced inverter I can find which meets UL1741, and does two-phase. The vendor says it can't work in a grid-tie environment, but the literature says it can. Have you any sage advice? Also, do I absolutely need the battery controller and the battery monitor and the Distribution Panel (and the smart home controller) - the vendor says the system won't work without these.

Yes, you should definitely start your own thread.

 

[JoeHam]

You will want the SW 4048 for your 48 V batteries, not the SW 4024.

I use one with the grid as a backup for a critical loads sub-panel I installed in my home.

I believe grid tie implies selling to the power company and all the BS that entails. I have no experience with that nonsense and likely never will ?.

I’m calling BS on what the vendor told you. You definitely will need a Gateway or a SCP or a ComBox to set up and monitor the inverter but that’s it. The rest of my equipment is Victron and basic electrical subpanel, wiring etc.

I will be away from the forum for a few days but let me know if I can answer any questions.

If you start a new thread I will find it.

 

[Wolfpv]

You will want the SW 4048 for your 48 V batteries, not the SW 4024.

I use one with the grid as a backup for a critical loads sub-panel I installed in my home.

I believe grid tie implies selling to the power company and all the BS that entails. I have no experience with that nonsense and likely never will ?.

I’m calling BS on what the vendor told you. You definitely will need a Gateway or a SCP or a ComBox to set up and monitor the inverter but that’s it. The rest of my equipment is Victron and basic electrical subpanel, wiring etc.

I will be away from the forum for a few days but let me know if I can answer any questions.

If you start a new thread I will find it.

Joe (are you a ham? I was long ago, WA6YJY)

Did you need the battery monitor box in order to hook up to the batteries? At least one vendor says that you can't hook to batteries without it.

-Steve

 

[Wolfpv]

Sorry u got no response. Are you still looking at this setup? I have the SW4024 inverter and can answer any of your questions.

 

[Wolfpv]

Sorry u got no response. Are you still looking at this setup? I have the SW4024 inverter and can answer any of your questions.

Hi - I've noticed you have a Schneider SW4024, and I'm thinking of getting the SW4048, but I have some questions:

• What other partner eqpt is needed (the vendors have a long list).
  • Battery Monitor (I'll be connecting to decent generic rack batteries)? I'm told the SW4024 simply won't work without it.
  • Distribution box?
  • For communication and control, I suppose I'll need something. Is the control panel (RNW865105001) adequate, or is the new insight home (RNW8650330) a better option?
• As far as you know, will this inverter do AC coupling (specifically with enphase M215 micro-inverters)?

It seems like all of the vendors are trying constantly to steer me to more and more expensive options. The SW4048 isn't free, but it's reasonably priced if it will work without all the other "stuff". Your help and comments are greatly appreciated.

-Steve

 

[BentleyJ]

I believe the SW4048 is a "baby brother" to the XW 6848 models but I haven't specifically read any of the manuals for the SW4048.
1) You don't need the Battery Monitor the inverter will work with most any 48V battery. However, without the Schneider Battery Monitor the State of Charge info is not available on the Xanbus thus without this value, SoC cannot be used to trigger a recharge cycle. I've seen some chatter regarding battery vendors that are working with Schneider to integrate communications with Xanbus but is not quite there yet.
2) For communication and control you should definitely go with the Gateway it communicates with the inverter and gives you remote access for monitoring and control. If you do add any charge controllers later the gateway will communicate with those also. If you really want to get fancy, the Gateway has RS-485 which can be used with a Programmable Logic Controller. I'm currently in the process of learning about the RS-485 interface.
3) If the SW4048 is compatible with AC Coupling then it should work just fine with M215's. I have 11 M250's & a Fronius string inverter both AC Coupled to a 6848.

 

[Wolfpv]

Bentley - Thanks for the quick and helpful reply. I've been going round and round with this, trying to avoid adding a $7K inverter setup to my $3K worth of batteries. I keep coming back to the SW4048. I'm just hoping it will frequency shift (AC couple) with the M215's. I haven't yet gotten a response from anybody who's had this particular combination. As far as battery communication, it would be nice, but I'm assuming that the latest battery BMS's can handle a constant voltage charge rate, and the inverter can serve that up. The batteries are EG4's

 

[BentleyJ]

The M215 microinverter was available in 2011 and then replaced by the M250 in 2013. The M250 model does shut down when the frequency shifts to 60.5Hz. As far as I know the older version of UL1741 (non SA, Rule 21) was in force in 2011 so the M215 should have no problem working with the SW4048. I was curious and looked up the SW4048 manual and it has a section describing AC Coupling, you should be good to go.

 

[JoeHam]

Joe (are you a ham? I was long ago, WA6YJY)

Did you need the battery monitor box in order to hook up to the batteries? At least one vendor says that you can't hook to batteries without it.

-Steve

Yes and I have no idea what battery monitor gizmo they might be taking about. Please provide a model number or something so we know what they are talking about.

As mentioned above, I have the ComBox although a SCP or Gateway could serve the same function.

I have zero interest in the batteries communicating with the inverter. The most elegant solution is the simplest one that does the job well.

My GYLL battery (the version before EG4) runs 24/7/365 happily this way. I check cell level voltages every few months with the monitoring program and it’s always been fine.

 

[BentleyJ]

I have no idea what battery monitor gizmo they might be taking about. Please provide a model number or something so we know what they are talking about.

Conext Battery Monitor

The Conext Battery Monitor indicates the hours of battery life left on your system while detecting for battery string imbalances.

solar.se.com

This is the battery monitor that is compatible with the Xanbus communication system on all the Conext devices. Its wildly overpriced, the inverters are already monitoring both DC and AC voltages and current coming and going. All they need to do is include a coulomb counter in the firmware to provide SoC instead of trying to rip off their customers. The really bad part is this device only monitors total pack voltage and mid pack voltage its not even a BMS.

 

[JoeHam]

Thanks @BentleyJ , that is definitely not necessary.

@Wolfpv I would suggest you get a different vendor promptly.

I got mine through NAWS which has no tax on solar equipment and gives you 5% off your first order when you sign up for yhe occasional email. I’m sure there are other honest vendors also.

Here is a link :

Schneider Electric Conext SW 4048 3,800 Watts, 48VDC Inverter/Charger for Split-phase 120/240 VAC

The Schneider Electric SW model inverters do NOT support stacking. These inverters are only designed to operate independently. If you need stacking ability, take a look at the XW line of inverters. Please email us or give us a call if you have any questions.

www.solar-electric.com

 

[ChrisG]

Thanks @BentleyJ , that is definitely not necessary.

@Wolfpv I would suggest you get a different vendor promptly.

I got mine through NAWS which has no tax on solar equipment and gives you 5% off your first order when you sign up for yhe occasional email. I’m sure there are other honest vendors also.

Here is a link :

Schneider Electric Conext SW 4048 3,800 Watts, 48VDC Inverter/Charger for Split-phase 120/240 VAC

The Schneider Electric SW model inverters do NOT support stacking. These inverters are only designed to operate independently. If you need stacking ability, take a look at the XW line of inverters. Please email us or give us a call if you have any questions.

www.solar-electric.com

@JoeHam , how are you telling your inverter when to charge, etc? I know if you use a Schneider Compatible closed loop battery/bms you don’t need the monitor at all.

 

[BentleyJ]

how are you telling your inverter when to charge, etc?

This is one of the quirks of Schneider Inverters. When using in AC coupled mode and there are no charge controllers, the only way to recharge the batteries is with the inverter charger but without the battery monitor there is no SoC data so you are left with only one option in the Inverter menu called Recharge Voltage. When the battery voltage drops below this setting it triggers a recharge cycle. (A recharge cycle is also triggered if there is a brown out or power outage) It would be super nice if the inverter had a clock based recharge function where you could top up the batteries once every few days or once a week or whatever when its in AC pass-thru mode with only minimal parasitic loads. Likewise if you need to use the Peak Load Shave feature every weekday evening there should be a way to trigger a recharge cycle every time a PLS session is used to be ready for the next day, but that feature is absent also.
Since we are Grandfathered in on the CA NEM 1.0 program for another 9 years, supposedly we will not be forced to Time of Use Metering until then but the utilities are pushing hard to transition everyone. In the meantime I'm investigating the RS-485 interface so I can use a PLC to program in the functions that are needed.

 

[Wolfpv]

Thanks for all the helpful information Joeham, BentleyJ and ChrisG. I guess I'll go for the SW4048 inverter without all the ancillary C**p and see how she flies.

Incidentally, regarding Time of Use, it's worked well for me. I installed my first panels facing West so I'd maximize my afternoon revenue - Sell electricity in the PM and charge my Tesla at midnight. Now I have more panels, but we now have a local community power company option which pays for overproduced power at the yearly "True-up" at prevailing rates (PG&E paid at some production cost rate, about $.02 per KWH). So now I get free power, free transportation (via Tesla) and get a check for $1000 at the end of the year. All that with an extensive (48 250-280W panels) but inexpensive solar system I installed myself. It's been about 5 years and it's fully paid back the investment, and then some. I'm a happy camper.

 

[JoeHam]

@JoeHam , how are you telling your inverter when to charge, etc? I know if you use a Schneider Compatible closed loop battery/bms you don’t need the monitor at all.

Simple voltage trigger set in the CSW4048.

Solar does almost all my charging and the 4048 charger has to kick in once or twice a month.

Most of the time I have the grid backup breaker turned off to reduce idle consumption from the grid. If we’re going to have a string of cloudy/rainy days then I leave the grid backup on.

For giggles I did add the Victron SmartShunt to watch the ins and outs (coulomb counting) but it’s absolutely not necessary.