Schneider Conext XW and GenSupp Plus

I tested this and it does work. But your loads have to exceed your GenSupp amps setting to get it to work. I have that set to 15 amps for our generator. I started it and was charging batteries at full gen output to test it. Then I turned on some test loads and got L1 up to 26 amps while L2 was at 16 amps load. It kept the L1 leg on the generator at 15 amps while 26 amps was going to the load on that leg (although it dropped the charger as soon as the loads exceeded the GenSupp setting).

Near as I can tell, it works identical to using a PSX-240 (or similar) to balance the legs of a split phase generator. In the PSX-240 you hook L1 and L2 to the breakers and one breaker is hooked to the primary and other to the secondary, and the neutral is hooked to other leads on both the primary and secondary (the primary and secondary windings are identical). Then try to pull a big 120V load off either L1 or L2 and the split phase power source will stay perfectly balanced despite the 120V load and power flowing in the neutral.

This is exactly what is going on inside the XW. It hooks the transformer center tap to the AC2 neutral and you got a built-in balancing transformer for your generator - as long as the inverter is in Gen Support mode.
--
Chris
«13

Comments

  • NorthGuyNorthGuy Solar Expert Posts: 1,925 ✭✭
    Re: Schneider Conext XW and GenSupp Plus

    So, it is only work when inverting, but does not work when charging. This makes sense. XW by itself can handle big imbalances while inverting. I was worrying about XW handling my loads because it is really hard to avoid imbalances, but, after testing, it handled all reasonable imbalances very well. Looks like it still not a problem when generator is added.

    PSX-240, however, would work with charging too. The downside of PSX-240 is that it has 5-7% of losses. In XW, you get it "for free".
  • ChrisOlsonChrisOlson Banned Posts: 1,807 ✭✭
    Re: Schneider Conext XW and GenSupp Plus

    I have measured the loaded power consumption of the PSX-240 at less than 12 watts with a 2 kVA imbalance and ~55 watts @ 4.5 kVA. So the insertion loss for the PSX-240 is very, very low with loads balanced within a couple kW. The transformer will actually handle 60 amps on a balanced load. It's 6 kVA rating is what it will handle for imbalance. If you examine the windings of a PSX-240 they appear to be 10 AWG and the resistance of the primary and secondary is very low.

    The transformer in the XW is the same deal - the I^2R loss in the windings will depend on the design, so it's not "free". So I now understand why Mike Mui (Schneider Tech Support) recommended to me to install the PSX-240 on the output of our generator - using it to balance the generator is more efficient than using the XW's internal transformer, and we get perfect generator balance during charging with the PSX-240 as well. Schneider was concerned about our small generator being disqualified by the XW during battery charging with a large leg imbalance issue because it can only supply 20.8 amps on either leg for 15 seconds and 15 amps continuous.

    For this test I measured the imbalance (or lack thereof) on the output of the PSX-240. During charging and normal operation I see imbalances on the legs on the PSX-240. But with GenSupp Plus enabled, and using Gen Support mode, the XW can balance your generator.

    Now, it says in the manual to not use a larger than 5 kW generator for Gen Support, and once you understand it, the reason for this is obvious. If you look at the wiring of an auto-transformer it is like a see-saw. With equal weight on each end of the see-saw (no leg imbalance) you are powering up the primary (or secondary) at 120+ on the sine wave and the other side at 120- simultaneously. And the see-saw is rocking back and forth 60 times per second. Nothing happens as long as the loads are balanced - there is no current flowing in the windings and the only losses is in switching the polarity of the core @ 60 Hz.

    As soon as you introduce an imbalance, current starts to flow in the windings and neutral, and the transformer does what auto-transformers do - the flux density on the heavier loaded side is higher and it assists the input on the other side of the transformer. There's a limit to how much one side of the transformer can assist the other side, and that limit is 5 kVA in the XW's transformer. Once you exceed that you get a circulating current between the legs and a loss in efficiency.

    I'm one of those weirdos that has to know how things work or it bothers me and I can't sleep at night. I'm satisfied that the XW is a solid unit and about the only way you could hurt one is to run over it with a bulldozer.
    --
    Chris
  • Dave AngeliniDave Angelini Solar Expert Posts: 4,477 ✭✭✭✭✭
    Re: Schneider Conext XW and GenSupp Plus
    ChrisOlson wrote: »
    I'm one of those weirdos that has to know how things work or it bothers me and I can't sleep at night. I'm satisfied that the XW is a solid unit and about the only way you could hurt one is to run over it with a bulldozer.
    --
    Chris

    Another way to hurt an XW is to place a book on the convection vent at the top and run the unit for months in a power shack in the desert. There were months of fault/warnings in the log.

    Hey Chris, so in your opinion, if you have the auto transformer for balancing a 2 leg generator, how would you "program" to get the best out of a 2KW single leg honda driving an XW split phase? I am assumming that you re-wire the the auto-trans to take a single leg and output 2 legs into the XW. When I have tried this it just drops the gen when a hair dryer comes on. The SW was better but it was single phase. I guess it is in the math....
    Thanks for the post!
    "we go where power lines don't" Sierra Mountains near Mariposa/Yosemite CA
     http://members.sti.net/offgridsolar/
    E-mail [email protected]

  • NorthGuyNorthGuy Solar Expert Posts: 1,925 ✭✭
    Re: Schneider Conext XW and GenSupp Plus
    ChrisOlson wrote: »
    I have measured the loaded power consumption of the PSX-240 at less than 12 watts with a 2 kVA imbalance and ~55 watts @ 4.5 kVA. So the insertion loss for the PSX-240 is very, very low with loads balanced within a couple kW. The transformer will actually handle 60 amps on a balanced load. It's 6 kVA rating is what it will handle for imbalance. If you examine the windings of a PSX-240 they appear to be 10 AWG and the resistance of the primary and secondary is very low.

    That's real good efficiency, closer to 99%. I didn't know they were that good. May be I should consider one.
    ChrisOlson wrote: »
    The transformer in the XW is the same deal - the I^2R loss in the windings will depend on the design, so it's not "free".

    It is "free" in a sense that you're already using it, so there's no additional losses from balancing. I'm not sure, but it is quite possible that losses may become smaller because of the balancing.
    ChrisOlson wrote: »
    ... we get perfect generator balance during charging with the PSX-240 as well.

    Could you explain more on that. In the XW there's a "Breaker size" setting for AC2. If the (charging current + load) on any leg approaches 80% of that, XW dials down the charhing and, in case of a small generator, may drop it completely. You probably have it set to 19A or so. Say, you get 0-15A load on L1 and L2. Because 15A is close to 80% of 19A, the charging gets completely eliminated. The load is then changed to [email protected] by PSX-240. In this situation, generator is loaded to only 50%, but there's no charging taking place to utilize the other 50%.

    What I would want to see in this situation is 7.5A charging, so the load becomes 7.5-22.5A, which then is translated to 15-15A (or [email protected]) at the generator. Generator would work at 100%, half would go to loads and half would be used by charging. That, in my mind, would be balancing.
  • ChrisOlsonChrisOlson Banned Posts: 1,807 ✭✭
    Re: Schneider Conext XW and GenSupp Plus
    NorthGuy wrote: »
    Could you explain more on that. In the XW there's a "Breaker size" setting for AC2

    Correct. With the PSX-240 on the output of the generator the generator itself always stays balanced so full power from the generator is available for either leg, even at a 100% imbalance (like your 0A-L1, 15A-L2 example). This prevents the XW from dropping the generator. The output of the PSX-240 isn't balanced, but the XW doesn't expect it to be - it only expects it to remain within spec for voltage and freq. And that's what the PSX-240 does for the generator - that 0A-L1, 15A-L2 example that you gave would put a small generator into overload on one leg (sometimes causing it to drop out of spec). With the transformer the generator is only 50% loaded (or whatever) with that imbalance so it doesn't care.

    The XW is way better at handling leg imbalances than the generator is. The PSX-240 on the generator's output makes it more capable (100% possible imbalance) than the XW (75% max imbalance). And that keeps XW happy with the generator's output.
    --
    Chris
  • NorthGuyNorthGuy Solar Expert Posts: 1,925 ✭✭
    Re: Schneider Conext XW and GenSupp Plus
    ChrisOlson wrote: »
    And that's what the PSX-240 does for the generator - that 0A-L1, 15A-L2 example that you gave would put a small generator into overload on one leg (sometimes causing it to drop out of spec). With the transformer the generator is only 50% loaded (or whatever) with that imbalance so it doesn't care

    So, with PSX-240, your generator can take [0A-L1,30A-L2] or [15A-L1,15A-L2] or [30A-L1,0A-L2]. The XW's "AC2 Breaker" is just one number, which protects the generator from overload.

    If you set it to only allow 15A (by setting AC2 breaker to 19A), then it will not let generator handle [0A-L1,30A-L2] or [30A-L1,0A-L2] even though it's perfectly good with the generator.

    If you set it to allow 30A (by setting AC2 breaker to 38A), then it will let generator any of [0A-L1,30A-L2] or [15A-L1,15A-L2] or [30A-L1,0A-L2], but if [30A-L1,30A-L2] comes in, it'll overload the generator and XW will have to drop it.

    So, how did you set the AC2 breaker size?
  • ChrisOlsonChrisOlson Banned Posts: 1,807 ✭✭
    Re: Schneider Conext XW and GenSupp Plus
    NorthGuy wrote: »
    So, how did you set the AC2 breaker size?

    I have it set to 20A, which is what the generator will actually put out in what is called "iAVR" mode. Our Honda generator is somewhat of a strange unit. It has a continuous (prime) rating of 3.6 kVA. But it will produce 4.0 kVA for 30 minutes and 5 kVA for 15 seconds and maintain perfect 120/240V and 60 Hz. I have never seen the XW spit it off yet because it doesn't like its output. Not once.

    But the difference may be that I am using Gen Support and I have the Gen Support amps set at 15. So if the generator gets to > 15 amps output instead of telling it to take a hike the XW drops the charger and supports the gen.
    --
    Chris
  • NorthGuyNorthGuy Solar Expert Posts: 1,925 ✭✭
    Re: Schneider Conext XW and GenSupp Plus
    ChrisOlson wrote: »
    But the difference may be that I am using Gen Support and I have the Gen Support amps set at 15. So if the generator gets to > 15 amps output instead of telling it to take a hike the XW drops the charger and supports the gen.

    I see, so the Gen Supports comes before AC2 breaker is hit, and it starts supporting the generator.

    How are you going to charge the batteris? You probably need at least 15A for this. That's 7.5A on L1 and 7.5A on L2. Any time a single-legged 8+A load comes in, the leg will hit 15A, it'll be dropping charging and start supporting.
  • ChrisOlsonChrisOlson Banned Posts: 1,807 ✭✭
    Re: Schneider Conext XW and GenSupp Plus
    NorthGuy wrote: »
    How are you going to charge the batteris? You probably need at least 15A for this. That's 7.5A on L1 and 7.5A on L2. Any time a single-legged 8+A load comes in, the leg will hit 15A, it'll be dropping charging and start supporting.

    No, 15A is 15A RMS on each leg. That amps setting is at 240V. It charges batteries just fine and as loads increase it dials the charger power back accordingly until the gen overloads - and then it supports the gen.

    Unless you change the jumpers inside for 120V output and change the firmware for it, all settings in your XW are for 240V, not 120V.

    On the Home Screen where it display watts, that's total watts of both legs combined, regardless of imbalance. But the menu settings are for 240V, and split phase power is L1 -> L2 with imbalance current flowing in the neutral.

    I haven't done enough testing to determine if the XW calculates amps including imbalance (sum of L1 and L2 divided by two) or excluding imbalance (real time peak on either leg).
    --
    Chris
  • ChrisOlsonChrisOlson Banned Posts: 1,807 ✭✭
    Re: Schneider Conext XW and GenSupp Plus
    NorthGuy wrote: »
    How are you going to charge the batteris? You probably need at least 15A for this. That's 7.5A on L1 and 7.5A on L2. Any time a single-legged 8+A load comes in, the leg will hit 15A, it'll be dropping charging and start supporting.

    No, 15A is 15A RMS on each leg. That amps setting is at 240V. It charges batteries just fine and as loads increase it dials the charger power back accordingly until the gen overloads - and then it supports the gen.

    Unless you change the jumpers inside for 120V output and change the firmware for it, all settings in your XW are for 240V, not 120V.

    On the Home Screen where it display watts, that's total watts of both legs combined, regardless of imbalance. But the menu settings are for 240V, and split phase power is L1 -> L2 with imbalance current flowing in the neutral.

    I haven't done enough testing to determine if the XW calculates amps including imbalance (sum of L1 and L2 divided by two) or excluding imbalance (real time peak on either leg).
    --
    Chris
  • NorthGuyNorthGuy Solar Expert Posts: 1,925 ✭✭
    Re: Schneider Conext XW and GenSupp Plus
    ChrisOlson wrote: »
    No, 15A is 15A RMS on each leg. That amps setting is at 240V. It charges batteries just fine and as loads increase it dials the charger power back accordingly until the gen overloads - and then it supports the gen.

    I found that mine does it differently. I don't know about GenSupport but the AC2 Breaker operates on the highest of L1 and L2 currents, not on average. As the highest of two starts hitting the limit, it starts to dial back. Charging is, however, always equal on both legs. For example, if you would have 15A limit, and it's a 10A load on one leg, you get only 5A charging (5A on one leg and 5A on the other leg). so that overall [load+charging] becomes 15A on one leg and 5A on the other. At least that is how mine is doing this.

    May be I have an obsolete firmware. What's your firmware version?
  • inetdoginetdog Solar Expert Posts: 3,123 ✭✭✭✭
    Re: Schneider Conext XW and GenSupp Plus
    NorthGuy wrote: »
    May be I have an obsolete firmware...
    Usually the answer to that is the same as the answer to "Do you have a Schneider product?" :-)
    SMA SB 3000, old BP panels.
  • Blackcherry04Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    Re: Schneider Conext XW and GenSupp Plus
    inetdog wrote: »
    Usually the answer to that is the same as the answer to "Do you have a Schneider product?" :-)
    Or you can ask the distributer how many years has it been sitting in your warehouse.
  • ChrisOlsonChrisOlson Banned Posts: 1,807 ✭✭
    Re: Schneider Conext XW and GenSupp Plus
    NorthGuy wrote: »
    I found that mine does it differently. I don't know about GenSupport but the AC2 Breaker operates on the highest of L1 and L2 currents, not on average. As the highest of two starts hitting the limit, it starts to dial back. Charging is, however, always equal on both legs. For example, if you would have 15A limit, and it's a 10A load on one leg, you get only 5A charging (5A on one leg and 5A on the other leg). so that overall [load+charging] becomes 15A on one leg and 5A on the other. At least that is how mine is doing this.

    May be I have an obsolete firmware. What's your firmware version?

    We have 1.07 firmware.

    Ours does the same thing as you describe with charging, which I would consider completely normal for a split phase inverter. Like I said, I haven't tested it enough to know if it's using the peak of either leg or the average because we haven't run it much out of balance when I've been watching it. I have to put my clamp-on meters on it to know what it's doing, and the first time I did that I tested that GenSupp Plus to see what it does, and was quite pleased to see that it works.

    What I got confused over is when you said:
    You probably need at least 15A for this. That's 7.5A on L1 and 7.5A on L2.

    Ours definitely does not work that way. 15 amps is 15 amps on BOTH legs, not 7.5 on L1 and 7.5 on L2. I'm going to do some fiddling with it tomorrow when I get some time with some imbalances and figure out if it uses the high leg for determining generator load. I'm pretty sure, like you say, that it has to because it would take some wizardry in there to do it any other way. I think with our auto-transformer on the generator we got considerable leeway because I am able to use the full output (overload) rating of the generator for the AC Breaker size without actually overloading the generator - AND I got the inverter set to start Gen Support before that happens.

    I dunno - it works so seamlessly here that I'd have to deliberately screw something up to invent a glitch in it.
    --
    Chris
  • NorthGuyNorthGuy Solar Expert Posts: 1,925 ✭✭
    Re: Schneider Conext XW and GenSupp Plus
    ChrisOlson wrote: »
    We have 1.07 firmware.

    That's what I have too. (inetdog and BC4 - are you listening? :p)
    ChrisOlson wrote: »
    Ours does the same thing as you describe with charging, which I would consider completely normal for a split phase inverter.

    I guess you're right. I just do not like that this keeps the generator underloaded.
    ChrisOlson wrote: »
    What I got confused over is when you said:
    You probably need at least 15A for this. That's 7.5A on L1 and 7.5A on L2.

    I probably misunderstood you. I thought your generator was 30A 120V (probably because you used it in your 120V before). And you use PSX-240 to convert 120V to 240V. To get a reasonable current to batteries, your generator would need to produce at least [email protected] When you take 15A from 120V generator, you get 7.5A on L1 and 7.5A on L2 on the the other side of PSX-240 and on XW. That's what I tried to say. I'm really bad at explaining things.
  • ChrisOlsonChrisOlson Banned Posts: 1,807 ✭✭
    Re: Schneider Conext XW and GenSupp Plus
    NorthGuy wrote: »
    I probably misunderstood you. I thought your generator was 30A 120V (probably because you used it in your 120V before). And you use PSX-240 to convert 120V to 240V.

    Ah, yes OK. That's what we did originally. That was what Mike at Schneider recommended. I was the one that got the wild hair to put the generator on 240V output (it will do either full power 120 or 240) and use the transformer on the inverter output to balance everything. That didn't work because the generator could not carry the loads by itself on leg at only 15 amps.

    So I put the transformer back on the generator. But also like I said before, our Honda is a not-normal generator from the standpoint that it's what any other manufacturer would call a 4,000 watt generator. You pull the others down to 5,000 watts (125% of "rated" output) and they'll fall flat on their face. The Honda don't. It's computer-controlled engine and generator will deliver 125% of "rated" for a full 15 seconds and maintain 120/240 and 60 Hz - and then the worst thing that happens if you leave it at that load level is that the voltage starts to drop very gradually to where after about 5 minutes at that load the voltage will drop to about 112/224 but the freq is still at 60 Hz. Due to the voltage drop as the stator windings heat up under overload the actual output ends up being about 4.7 kVA after five minutes.

    There are very, very, very few generators that can do that. Usually that sort of overload capability is only found in commercial/industrial grade prime power generators. Honda, a company that prides itself on not being outdone in the engineering dept no matter what it takes, put it in a portable, for pete's sake.
    --
    Chris
  • Blackcherry04Blackcherry04 Solar Expert Posts: 2,490 ✭✭✭
    Re: Schneider Conext XW and GenSupp Plus
    NorthGuy wrote: »
    That's what I have too. (inetdog and BC4 - are you listening? :p)

    .
    Since the XW6048 been around since 2007, I am sure there is some in stock somewhere that is not up to date. I don't blame Schneider though, once it goes out their door it becomes a issue for the dealer to take care of. Of course these days of the Internet Purchasing , you get what you get. I am sure NAWS would never sell a Inverter with out of date firmware. The last revision I think was 2009-2010 so it's been awhile.
  • ChrisOlsonChrisOlson Banned Posts: 1,807 ✭✭
    Re: Schneider Conext XW and GenSupp Plus

    I haven't studied the manual or read about what it takes to upgrade the firmware in a XW. But I think it would be easy to do should it become necessary. Someplace I read about a XW config tool (I'd have to read more about it at this point) so it's probably not a lot different than upgrading the firmware in my Classic 150's.
    --
    Chris
  • NorthGuyNorthGuy Solar Expert Posts: 1,925 ✭✭
    Re: Schneider Conext XW and GenSupp Plus
    ChrisOlson wrote: »
    I haven't studied the manual or read about what it takes to upgrade the firmware in a XW. But I think it would be easy to do should it become necessary. Someplace I read about a XW config tool (I'd have to read more about it at this point) so it's probably not a lot different than upgrading the firmware in my Classic 150's.

    XW Config tool doesn't come cheap.
  • ChrisOlsonChrisOlson Banned Posts: 1,807 ✭✭
    Re: Schneider Conext XW and GenSupp Plus
    NorthGuy wrote: »
    XW Config tool doesn't come cheap.

    No, but we bought our inverter from a brick and mortar local dealer, even thought it cost more than buying it online. The dealer has one of those things and if I need to use it they'll let me use it because I've done business with them for years.
    --
    Chris
  • mike95490mike95490 Solar Expert Posts: 8,284 ✭✭✭✭✭
    Re: Schneider Conext XW and GenSupp Plus
    ChrisOlson wrote: »
    I haven't studied the manual or read about what it takes to upgrade the firmware in a XW. But I think it would be easy to do should it become necessary. Someplace I read about a XW config tool (I'd have to read more about it at this point) so it's probably not a lot different than upgrading the firmware in my Classic 150's. Chris

    It's a mess to do. You have to find a dealer to borrow or rent the tool. ( The Implanter ). The only other option is to use the Gateway if you have one. Then you get your host computer to talk to the tool. Then after you finish and return the tool, you find that you didn't get the very latest version (they only email it out, no FTP site to pull it from) and you have to start over.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • ChrisOlsonChrisOlson Banned Posts: 1,807 ✭✭
    Re: Schneider Conext XW and GenSupp Plus
    mike95490 wrote: »
    (they only email it out, no FTP site to pull it from) and you have to start over.

    Actually, when I have requested tech information or a manual download from Schneider they have always sent me an email with a link where I can download the requested information. The link is usually good for like 24 hours, or whatever.

    Your description is about what I figured - it's a pretty simple process. Really no different than upgrading the firmware in a Classic controller, except different tools required.
    --
    Chris
  • Dave AngeliniDave Angelini Solar Expert Posts: 4,477 ✭✭✭✭✭
    Re: Schneider Conext XW and GenSupp Plus
    ChrisOlson wrote: »
    Actually, when I have requested tech information or a manual download from Schneider they have always sent me an email with a link where I can download the requested information. The link is usually good for like 24 hours, or whatever.

    Your description is about what I figured - it's a pretty simple process. Really no different than upgrading the firmware in a Classic controller, except different tools required.
    --
    Chris
    It is reasonably simple to upgrade firmware. One has to remember when this unit was developed there was nothing like this. Everything had to go back to the factory. Offgrid, the XW was the holy grail ! It is too bad they have not chosen to be more user friendly. Each transition from Trace to Xantrex to Schneider has made it harder to deal with for "do it yourself" types. They are great with their dealers and I have never had anything but great phone support in the field for offgrid. Your firmware probably has not been changed for 3 years and most of that was grid-tie issues.
    "we go where power lines don't" Sierra Mountains near Mariposa/Yosemite CA
     http://members.sti.net/offgridsolar/
    E-mail [email protected]

  • ChrisOlsonChrisOlson Banned Posts: 1,807 ✭✭
    Re: Schneider Conext XW and GenSupp Plus

    Mainly for NorthGuy,

    I have played with our Outback PSX-240 on the output of the generator, allowing the inverter to handle leg imbalances but keeping the generator balanced. And also on the output of the inverter, which leg balances BOTH the inverter and generator simultaneously. After switching it back and forth a couple times to test things, it is better on the output of the inverter. I got the transformer wired in to the main disconnect panel for the inverter with #8 Type SEOW cable (easier to bend around sharp corners), and the transformer is using the 240V from the inverter to power the 120V loads (we have separate panels for 120V and 240V being we used to have a 120V inverter).

    Attachment not found.

    The main advantage with using the auto transformer on the inverter output is that the inverter runs more efficient and has more capacity before it calls for the generator with Load Start. One of the side effects is that you get more power from the charger with the transformer on it. If you have a leg imbalance the XW will use the value from the highest loaded leg to de-rate the charger, leaving the other leg basically idling. With the legs balanced you get your full 80% of the AC2 Breaker setting, minus de-rate for loads, at all times.
    --
    Chris
  • NorthGuyNorthGuy Solar Expert Posts: 1,925 ✭✭
    Re: Schneider Conext XW and GenSupp Plus
    ChrisOlson wrote: »
    Mainly for NorthGuy

    Thank you Chris. So, the transformer on the output of the inverter solves all the imbalances problems at a cost of 1.5-2% loss. Perhaps, I need to do this too. I tweaked the breakers and moved them between L1 and L2 a lot, but no matter what I do one-sided loads keep showing up.
  • ChrisOlsonChrisOlson Banned Posts: 1,807 ✭✭
    Re: Schneider Conext XW and GenSupp Plus

    Yes, it does a beautiful job of balancing the inverter AND generator. I think the inverter runs more efficient when it's leg balanced and whatever losses there are in the transformer (which is very, very low) is made up for in increased inverter efficiency, so it's a wash.

    The only caveat is that you need to split out your 120V loads from your service panel and put them in a sub panel. For us this was no big deal because 120V is all we had for years, other than the well pump on a transformer. When we put in lots of 240V stuff here we put in a new 240V panel for it. I know from putting in generator transfer switches that when you remove 120V circuits from a service entrance panel that the wires don't always reach to put them into a sub panel. So it can be a pain.

    I believe that for most people it wouldn't be necessary to leg balance the XW. But if you want to push the inverter and charger to its raw limits the transformer makes a world of difference.
    --
    Chris
  • BB.BB. Super Moderators, Administrators Posts: 29,189 admin
    Re: Schneider Conext XW and GenSupp Plus
    ChrisOlson wrote: »
    The only caveat is that you need to split out your 120V loads from your service panel and put them in a sub panel. For us this was no big deal because 120V is all we had for years, other than the well pump on a transformer. When we put in lots of 240V stuff here we put in a new 240V panel for it.

    Chris, why separate out the 120 VAC loads? Is/was this a 120 VAC only panel?

    Otherwise, if you have (for example) a 120/240 VAC split phase panel with a jumper between the two 120 VAC legs, just remove the jumper and wire up the balancing transformer between the 120/240 VAC source and the main load panel (now wired to 120/240 split phase).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Dave AngeliniDave Angelini Solar Expert Posts: 4,477 ✭✭✭✭✭
    Re: Schneider Conext XW and GenSupp Plus

    Bill not sure why he is doing it but when you go from single to split panel with a split inverter there is balancing involved if you are running big 120 loads. It is not a problem with big 240 loads. Really not any different from an electrician balancing loads in a new power panel.

    Oh yea, the why? The XW split does not like big imbalances. That is why some folk will run them single phase.
    "we go where power lines don't" Sierra Mountains near Mariposa/Yosemite CA
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  • BB.BB. Super Moderators, Administrators Posts: 29,189 admin
    Re: Schneider Conext XW and GenSupp Plus
    Oh yea, the why? The XW split does not like big imbalances. That is why some folk will run them single phase.

    Understand that one. ;)

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • ChrisOlsonChrisOlson Banned Posts: 1,807 ✭✭
    Re: Schneider Conext XW and GenSupp Plus

    Bill, the transformer, going from split phase to split phase does not do a perfect job of balancing - just like the XW's internal transformer in GenSupp Plus where it hooks the transformer center tap to the AC2 neutral. It balances some, but not perfect.

    If you feed it split phase and pull 120V off it (step down mode), then it balances the inverter legs almost perfectly. With the transformer in step down configuration feeding the 120V loads, and the split phase loads coming direct off the AC disconnect panel for the inverter, it stays within a 1/2 amp between the two legs on both the inverter and the generator.

    Frankly, I think the auto transformer is a better option for leg balancing the inverter to get the most out of it at the highest efficiency than converting it to 120V and changing the firmware for it.

    Like I said, for most people who don't push it to the limits it's not going to be a big deal. But if you push the XW to its limits, both in inverting and charging, as well as your generator, the auto transformer works. With #8 wire into and out of the auto transformer you can feed it 25 amps split phase and get 50 amps surge and 40 amps continuous @ 120V out of it. If you got more than 40 amps of continuous and simultaneous 120V loads you should be looking at converting some things to 240V in your house, is my opinion. So the PSX-240 is sized about right for the XW6048 to use its full rated output on 120V loads (if you have to).

    You can get #6 wire into and out of the PSX-240. But it's a bear because #6 THHN is hard to bend around corners, and there's a limited amount of room in the PSX-240's wiring raceway. So a 40 amp 120V panel works out good with #8 wire feeding it, and is fairly easy to wire up.
    --
    Chris
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