Xantrex XW6048 configuration help

Hi all,

I just recently set up a 4kw array, with an XW6048 inverter, I configured the system via the system control panel, to allow grid support, and disable sell mode. (ie i do not want to back feed/sell to the grid)

What my ultimate goal is to use power from my array and batteries to power my loads during the day, (any excess goes to batteries) and at night if needed the grid will pass through the inverter to help sustain the loads. According to the manual this can be achieved by the method i mentioned, (ie. grid support with sell disabled.) So far it appears to be working but i have noticed a few things that did not make sense, and was hoping someone could explain them.

The current status says grid support.
the battery is -3.9amps
the load is -150watts,
AC1 is 12 watts

1. every now and then AC1 shows as having a Negative power value, (i thought this meant it was selling to the grid?) Is this what is happening?
2. right now i have all loads turned off by a breaker, and the "load power" display on the control panel, has a negative value of aprox 150watts? what does this mean? is it using 150watts? this seems like a lot of standby power, since i know that there is currently 0 current draw from my loads.
3. I have the inverter disabled and the battery is showing a -3.2amp under status? is it using battery power? The inverter just has a line across the screen, and it sounds like it is inverting buy i am not positive?

Any help would be Greatly appreciated.

Thanks,
Chris

Comments

  • Joe_BJoe_B Posts: 318Solar Expert ✭✭✭✭✭✭
    Re: Xantrex XW6048 configuration help

    Chris,

    I need to know a bit more about how you have your system set up. What do you have the grid support voltage set to? do you have load shaving enabled? are you using the XW-SCC and are they networked? Typically if the grid is present and qualified, the inverter itself will draw about 50 watts from the grid not 150.

    The grid power display is normally negative to show a draw from the grid. for example if the unit is in AC passthrough, the load will show X watts positive and the grid number will be X watts + about 50 watts but the value will be negative. So if your loads are drawing say 500 watts, the grid draw will be bouncing around -550 watts give or take.

    Hope this makes sense,

    Joe
  • SolaRevolutionSolaRevolution Posts: 407Solar Expert ✭✭✭✭✭✭
    Re: Xantrex XW6048 configuration help

    Try isolating the inverter to find out where the power is going. Or for that matter, if it really is going somewhere.

    1. Turn off the PV input.
    2. Check all of your meters when you turn off the load breaker. (Inverter Load Out)
    3. Check all of your meters with the Grid Input breaker off.
    4. Check with grid support off.
    5. Check as you turn the PV back on.

    Try as many combinations of these as you can think of.
    Write down all of your meter readings including AC1 and Load (voltage and current), battery (voltage and current)
    for each test condition.
    Verify with a multimeter if you have one.

    Doing the above will often make apparent something you may have overlooked or if something is drawing when it should not be.
    I have found "virtual" phantom loads in multiple inverter systems before but not, as far as I can remember, in a single inverter system.

    If you do all of the above before you call tech support you may be able to gain a better understanding of your system and have a more informative conversation when you are able to talk to someone about it.

    -Alex
  • chris30559chris30559 Posts: 7Registered Users
    Re: Xantrex XW6048 configuration help

    Hi all,

    I have been experimenting with settings and recording values to try to figure this out today. I think i figured out some things, but got more questions on other things.

    First things first, There is NO load connected to the inverter at this time, if i run the inverter with Grid support disabled, (ie. just off xantrex mppt 60A charge controller and batteries supplying the inverter.)The status says Invert, the load hangs out around 30 watts. This i believe is normal for the inverter to consume about 30 watts at idle. Also note that 30watt consumption is a positive number. If i add a load, the load value goes up still a positive number. and the battery shows a negative number for amps (if there is no PV input or it is lower than the consumption.)
    This makes sense to me and i fully understand what it is doing.

    Ok, now i will do the same thing, (NO output load connected. ) but this time i will enable grid support with sell disabled. after the AC is qualified, the load shows a negative 150watts, AC1 shows a positive 10-20 watts and the battery is showing a negative number for amps, aprox 3.7-3.9. At this time there is still nothing at all connected to the output of the inverter. Now the manual says that when AC1 is a negative number it is selling to the grid, but i cannot find anything about there being a negative value for the load.
    Now when i add a load to this scenario, The load goes to a positive value (similar to the off grid scenario) but now the AC1 goes to a negative value. (according to the manual this means it is selling? unless it is a complete typo in the manual?)

    Now the next problem i just encountered today is that when i am grid support with sell disabled, and i turn on a very high load, it initially pulls from charge controller and batteries. After a few seconds it stops and hands off all the load to the grid AC1-which is now displaying a negative wattage. after another few seconds the inverter starts to balance out and splits the load between grid and battery/PV array. This is great, and i like this function, but it seems to give the grid to much load? like right now my batteries are full ( i am using 2stage charge by the way) and i have at least 2kw worth of power available from the PV's but the inverter is only taking about 1kw worth of power and giving the rest say 500watts to the grid. I take it the inverter balances the loads based on a percentage between the batteries and grid? if so how do i force it to use more power from the PV's since it is defiantly available. It just seems like a waist, since the charge controller is done charging the batteries, it throttles back and wont seem to provide all the power it is capable.

    I tried to change the grid support volts from 50volts to maybe 49 volts, but when i try to change it, it will not let me? this is another problem i am having. it simply says i cannot change that value at this time. I have tried with everything on/off, etc, etc, and i can only increase that value an not go down, Even though the manual says it can go as low as 46volts.

    Thanks for any and all help.
    Chris
  • Joe_BJoe_B Posts: 318Solar Expert ✭✭✭✭✭✭
    Re: Xantrex XW6048 configuration help

    Hi Chris, what you are describing is normal. There IS a typo in the manual with regard to the sign on the AC1. Also if you want to change the GSV lower, then you will have to lower your LBCO in the inverter section. It is a subtle point in the manual but the lower limit of the GSV is governed by the LBCO voltage. I cant remember the limit but it is something like GSV can only be 2 volts (or something) greater than the LBCO, try setting the LBCO voltage a few volts lower and then you should be able to change the GSV value to a lower number.

    As far as the point where the inverter will share load with the grid, you use load shaving to change it. Enable load shaving and set it to zero amps and that will be the best you can do, It will say load shaving on the inverter home screen when this happens and the AC1 load will be minimum.
  • sub3marathonmansub3marathonman Posts: 300Solar Expert ✭✭✭
    Re: Xantrex XW6048 configuration help
    Joe_B wrote: »
    Also if you want to change the GSV lower, then you will have to lower your LBCO in the inverter section. It is a subtle point in the manual but the lower limit of the GSV is governed by the LBCO voltage. I cant remember the limit but it is something like GSV can only be 2 volts (or something) greater than the LBCO, try setting the LBCO voltage a few volts lower and then you should be able to change the GSV value to a lower number.

    I'm not sure about changing that Low Battery Cutout Voltage. That value is there to protect your batteries. I regularly set the Sell Voltage at 52.8 V or so, much higher than the LBCO voltage of 46.5 V, and much more than a 2 V difference. If I then lower the Sell Voltage, closer to the LBCO voltage, it will increase the grid output, at whatever rate the Maximum Sell Amperage is set at. These values are in the Advanced Settings, Grid Support portion of the menu. And then, once the batteries have output the energy, it will reduce the battery output amperage to zero after a bit of time, and you will stop selling to the grid. If there is further PV input, it can and will continue selling at whatever rate the MSA is set at. If the MSA is less than the PV input, the batteries will start charging again. If the batteries reach full charge it will stop the PV output.

    I believe I can set the lowest Sell Voltage less than 48.5, so it might be just a 1 V difference that is allowed.
  • Joe_BJoe_B Posts: 318Solar Expert ✭✭✭✭✭✭
    Re: Xantrex XW6048 configuration help
    I'm not sure about changing that Low Battery Cutout Voltage. That value is there to protect your batteries. I regularly set the Sell Voltage at 52.8 V or so, much higher than the LBCO voltage of 46.5 V, and much more than a 2 V difference. If I then lower the Sell Voltage, closer to the LBCO voltage, it will increase the grid output, at whatever rate the Maximum Sell Amperage is set at. These values are in the Advanced Settings, Grid Support portion of the menu. And then, once the batteries have output the energy, it will reduce the battery output amperage to zero after a bit of time, and you will stop selling to the grid. If there is further PV input, it can and will continue selling at whatever rate the MSA is set at. If the MSA is less than the PV input, the batteries will start charging again. If the batteries reach full charge it will stop the PV output.

    I believe I can set the lowest Sell Voltage less than 48.5, so it might be just a 1 V difference that is allowed.

    The OP states that he is running with grid support enabled and sell disabled, so he cannot set sell voltage.

    With regard to the LBCO, I agree, I cannot get a coherent answer from Schneider tech support as to why GSV and LBCO are tied together. It makes no sense to me. So Unfortunately, you have to modify LBCO in order to get any performance out of grid support. This is why most people who have implemented this system use some sort of external battery monitor like the Victron.

    As to the effectiveness of the LBCO, it is a voltage and not an SOC and when the inverter is loading the battery bank, the voltage will drop below the LBCO much faster than if the bank was unloaded. LBCO is really not a true indication of SOC as the load is varying.

    In my system, I set the battery monitor up to shut down the inverter at a 50% SOC and then I dont have to worry about the LBCO value.
  • SolaRevolutionSolaRevolution Posts: 407Solar Expert ✭✭✭✭✭✭
    Re: Xantrex XW6048 configuration help

    Some thoughts-

    With a 4kW array your XWMPPT60-150 charge controller is overloaded. This is not likely to be the cause of the issue but it can have an effect on charging algorhythms. I'm not sure that it will damage your charge controller but you are certianly not getting full output capacity from your array.

    I am curious about the size of your battery. Without Sell enabled, your array and charge controller are operating like they would in an off-grid system with the generator on full-time. Is your battery sized appropriately for a 4kW array? If your battery is much less than 500 amp hours you may be having some other charging algorythm issues.

    Also, you may have some terms mixed up.

    GSV - Grid Support Voltage
    GSV - Generator Start Voltage
    The lowest Generator Start Voltage does correlate to the LBCO (Low Battery Cut Out) and the LBCO delay. The settings are related because the Gen Auto Start needs to turn on the generator before the inverter shuts down from a low battery voltage condition.

    Sell or no sell, the Generator Support Voltage is not tempurature corrected but the Charge Controller output is. (Is this a manual Typo in the Op guide Grid Support Settings section?) This could make it so your Grid Support Voltage is lower than your temp adjusted float voltage when the batteries are cold or higher when the batteries are warm.

    For Selling, "Sell" mode needs to be enabled and Grid Support Voltage needs to be set above the charge controller's float setting or else the charge controller will regulate the PV current while you want it to be sending everything to the grid.

    No solutions offered here but I hope this helps.
  • chris30559chris30559 Posts: 7Registered Users
    Re: Xantrex XW6048 configuration help

    Thanks Everyone for all the help thus far,

    I have been experimenting with LoadShaving, and have gotten a larger charge controller (80amp outback). Everything has been working much better, Most of the time Load shave is working well my grid draw is generally less than 100watts, (i have it set to 0Amps, to minimize my grid usage).

    Now however i have another issue. It seems that load shave is not consistently on? every now and then i check the XW control panel, and it shows Grid support under status? even though i have plenty of battery power and it is in the middle of the day, (i have load shave set to 9am to 9pm) Sometimes it shows load shave and sometimes grid support? what am i missing now..

    logically i would think if i have load shave on from 9am - 9pm, then the inverter should be minimizing the grid usage during this time, and outside of this time it should go to ACpassthrough.

    like i said most of the time load shave is working OK, but sometime it goes to grid support and does not minimize grid draw. Also does the grid support voltage have any effect when load shave is on? i have it currently set to 49.5 volts, I would like to go lower to 49 maybe but then i would have to lower LBCO more.

    Also one last thing, even now i am looking at the control panel,
    11:02PM it says grid support,
    battery is -3.8v @49.5v
    Load is 473w
    AC1 is -611w?

    Why is the inverter drawing more watts from the grid, than the load is??

    Thanks for the Help!
    Chris
  • Joe_BJoe_B Posts: 318Solar Expert ✭✭✭✭✭✭
    Re: Xantrex XW6048 configuration help

    Chris,

    My system does exactly the same thing as yours. I have contacted X/S support numerous times about it and the best they can do is say that it is software bugs. The most I can get out of them on the grid draw issue is that it is incorrect and Ii have verified that with external metering. Just chaulk it up to crappy software. The load shave issue and grid support issue is also a bug. My system also bounces in and out of load shaving. So from what you have posted, you are doing the best you can get with it until X/S decides to do something about the bugs.

    now that the sun is getting better, I am going to try experimenting with sell enabled and sell amps set to 0. I believe that this might reduce the grid draw a bit more but wont be sure until I try some stuff. Kind of like tricking the firmware. Gotta love it huh?
  • chris30559chris30559 Posts: 7Registered Users
    Re: Xantrex XW6048 configuration help

    Hi Joe,

    Which Firmware do you have on your XW, is it 1.07, That is the newest one from what i can tell on Xantrex website. Mine is 1.05, and I am wondering if they fixed it in 1.07. I read the release notes about it, and i don't see any mention of a solution to our problem.

    Chris
  • Joe_BJoe_B Posts: 318Solar Expert ✭✭✭✭✭✭
    Re: Xantrex XW6048 configuration help

    Chris, I am running 1.07 BN3 but keep in mind that I have a 4024 and not a 48 so the firmware is somewhat different. The functionality or malfunctionality that you described is the same on my firmware.

    I will also add that I got this firmware directly from tech support before it was released on the website and when I upgraded, it fixed a few annoying bugs with the generator but I also lost the ability to look at faults and warnings on the SCP. Now I am forced to use the widget to look at faults. Fix one thing break another :-(
  • chris30559chris30559 Posts: 7Registered Users
    Re: Xantrex XW6048 configuration help

    One last question,

    I thought that i read somewhere on this site that when in Load shave mode, it remains in that mode until it draws the batteries down to LBCO+2v voltage. Can anyone confirm this? i cannot find where i read it, and the manual says that it will draw the batteries down to the LBCO voltage before it switches off. which is right?

    I want to create a good balance between my batteries and grid usage, i don't want to go to deep with the discharge of my batteries but i don't want the inverter to switch back to ACpassthrough when there is a intermittent heavy load on the batteries, "causing the voltage to drop down past the triggering level", (weather it is LBCO+2 volts or LBCO). from what i understand, Under heavy load (100amp draw) the voltage does not really give a good reading for battery state of charge. I am assuming that @100amps 46-47volt readings are more like 48-49v readings with no draw, but i have yet to experiment, does this sound like a reasonable assumption.

    right now i have my LBCO set to 45.5v with a 10 sec delay. the default is 44v which i felt was to low to start with, but now after seeing what happens when i have a heavy load this might need to be lowered back to default? Does anyone change this value?

    I am trying to keep my batteries in the 25-40% Depth of discharge window.

    Chris
  • Joe_BJoe_B Posts: 318Solar Expert ✭✭✭✭✭✭
    Re: Xantrex XW6048 configuration help

    Chris, the 2 volts above LBCO comes from the graph in the manual in the grid support section.

    As far as voltage, this is the big problem with these inverters, voltage is not a good way to determine trip points due to the varying loads. It is a compromize at best and this is why they also give a time associated with the voltage. The LBCO delay value will let it ride through momentary heavy loads.

    I have suggested to tech support that it would be great if they came out with a shunt that interfaced to the xanbus but I am getting the impression that development for this product is done so we are stuck with the voltage / time delay thing.

    I will add that I have been experimenting with switching off the grid supply with a relay controlled by the XW 4024 aux output. It seems that all of this grid support nonsense is eliminated when the XW is in invert mode. So I program the XW aux to turn on the grid only when the battery voltage drops below a certain value, if the grid happens to be down, then the generator start module will start the generator at a slightly lower voltage level. During the day, the solar chargers bring the batteries back up to snuff if the sun is shining. By doing this, it seems to just make it work a whole lot nicer than the grid support thing.
  • chris30559chris30559 Posts: 7Registered Users
    Re: Xantrex XW6048 configuration help

    Hi Joe,

    That is a great idea, I to have noticed the inverter works so much smoother without the grid connected, i find myself switching off the grid breaker more and more often.

    I think i will also try experimenting with a relay as well. Was wondering though, how do you avoid the Low voltage Alarm for the grid when you switch it on and off? Do you have grid support disabled entirely? if i leave it disabled i don't get an alarm, but then it defaults to AC pass through mode when grid is reconnected, which i guess is OK. ( I was thinking of trying to force the inverter to use 0% grid, by using the relay to disconnect the grid, and then when low on Battery, it would turn grid back on, then do its thing with grid support to balance the load, Instead of complete AC passthrough) I am also thinking i might need to add a delay timer for the relay. Otherwise i am suspecting it will cycle back and forth when the voltage is right around the trigger voltage.

    I was also thinking of using the AC2 input (generator support) as my Grid supply. Thinking that i could "trick" the inverter in thinking its completely off grid, and then when the batteries get low, it would start the generator (relay) and connect the grid to AC2. Then hopefully it would take just what it needs? and not divert all the load to the generator input. The manual doesn't really say it can do this, but i know its not a typical scenario.

    I think i will experiment with it this weekend.

    Thanks,
    Chris
  • SolaRevolutionSolaRevolution Posts: 407Solar Expert ✭✭✭✭✭✭
    Re: Xantrex XW6048 configuration help
    chris30559 wrote: »
    I was also thinking of using the AC2 input (generator support) as my Grid supply. Thinking that i could "trick" the inverter in thinking its completely off grid, and then when the batteries get low, it would start the generator (relay) and connect the grid to AC2. Then hopefully it would take just what it needs? and not divert all the load to the generator input. The manual doesn't really say it can do this, but i know its not a typical scenario.

    That is a good idea.
    Do you have the AGS?
    I suggest you use mode 14.

    Alex
  • Joe_BJoe_B Posts: 318Solar Expert ✭✭✭✭✭✭
    Re: Xantrex XW6048 configuration help

    Hi Chris,

    My experimentation is essentially complete and it works pretty well with one exception. There were three primary reasons I did this, first of all, when in grid support and with full sun on my panels, the stupid inverter would command the SCC's to unload the panels in favor of drawing about 50% of the load from the grid. Really a severe bug IMO. Secondly, when running in grid support, the inverter constantly tugs on the grid and the loop is really unstable making the readouts unusable and occasionally actually pushing power out on the grid even with sell disabled and sell amps set to zero (very bad). Too bad the SW engineer didnt know how to stabilize a PID loop. Finally, all of the rediculous AI faults with no ability to reset them.

    So I have a victron BMV-600 and that has a true SOC on the battery. I used the alarm relay to control the contactor. By setting the discharge floor to 75% and the clear relay to 90%, when ever my battery bank is above 90% (charged by the panels) the contactor opens and disconnects the inverter from the grid. The panels will support all the loads with zero grid draw, the readoputs stabilize and all is happy. Yes, there is an alarm generated but I just ignore it by turning off the beeper in the SCP. After the sun goes down, the batterys begin their discharge and continue to support the loads until they discharge to the floor I set in the monitor (75%) and then the contactor closes and the unit goes into the cursed grid support mode. I have my unit set to only allow the bank to discharge about to 70% (arrived at by experimentation by playing with the grid support voltage) and then it transitions to AC passthrough. It rarely makes it that low but it is a good safety in case you dont get a full charge due to clouds, etc.

    As soon as the sun comes out, the SCC's will begin to charge the battery and soon after that, the unit will enter grid support mode at a low level. Most of the solar harvest will again be diverted to re-charging the battery bank and as the voltage rises, the inverter will use more battery and less grid until I hit the 90% mark on the SOC meter. At this point, the contactor will disconnect from the grid and the system will run off the panels.

    It all works quite well with one exception, you have to disable the grid charger. Seems that yet another bug in the software will ignore the recharge voltage setting on the charger and default it directly to bulk, which is bad. So I have no solution to the charger issue at this point. I do have an AGS but it does not charge if the generator starts, it will default to AC passthrough and just support the loads. If I want to charge the battery off the grid (rarely) I have to manually enable it.

    The sad part of all this is the hardware in the inverter can do all of this if there was a mode for it. I have talked to the guys at Schneider no end about this and they are not interested in hearing it so this is my solution to bypass all their crap software with simple relay logic.

    Good luck,

    Joe

    ETA: I thought about using the AC2 input for the grid and it might work for you but I use the gen support mode and it only works on AC2. Also, I like the auto transfer feature I get by using AC2 for the generator and AC1 for the grid.
  • Joe_BJoe_B Posts: 318Solar Expert ✭✭✭✭✭✭
    Re: Xantrex XW6048 configuration help

    Chris / Alex,

    Checked my system with the "AC2" trick tonight and it wont work, what ever input (AC1 or AC2) has a qualified AC input, regardless of the priority, the inverter will use it. You cant disable it without disconnecting it :-(
  • Joe_BJoe_B Posts: 318Solar Expert ✭✭✭✭✭✭
    Re: Xantrex XW6048 configuration help

    Arrg this is so frustrating, I thought I had a solution to getting the charger to work when AC2 was active but alas not. You would think that this paragraph on page 3-10 of the manual would allow it:

    CHARGER BLOCK:

    Sets the time to halt charging on AC1 (Grid). The AC2 (Gen) port is unaffected by the
    charger block settings. The charger block start and stop settings allow you to select
    when the charger stops charging on AC1. To disable the charger block function, set
    Chg Block Start and Chg Block Stop to the same time. See “The Xantrex XW
    system will still allow manual equalize charging when the boost absorption voltage is
    implemented.” on page 3–17.


    But unfortuantely it is incorrect. It DOES block charging on AC2 as well as AC1.

    They also state it on page 3-17 as well:

    During the charger block period, no charging on AC1 occurs even if the batteries
    discharge below ReCharge Volts setting. However, a generator connected to
    AC2 (in the absence of utility/AC1 power) or a Xantrex XW Solar Charge
    Controller may charge batteries during the charger block period. AC priority must
    be set to AC2 to charge batteries with a generator connected to AC2 during the
    charger block period.


    So much for XW hackware working as stated in the manual.
  • DustyDusty Posts: 271Solar Expert ✭✭✭
    Re: Xantrex XW6048 configuration help

    SolaRevolution,

    I have a couple questions about your quote below:

    When you refer to the "charge controller's float setting," are you referring to the 6048's charger or the MPPT-60? If it's the MPPT-60, do you mean the "recharge volts" parameter?

    However, if you mean the "float" setting under the MPPT-60 custom battery setting, mine is still set to default (not sure what that is for a 48v battery bank, but the sample in the operations guide says 14.4 for a 12-volt system, so I'm guessing it's 57.6V for a 48 volt system. I'll check that when I get home tonight). My sell amps is only set to 5 since I only have about 1.1KW PV until the new panels arrive and I don't want to overload my small 110 AH battery bank.

    I'm still testing this setup, but right now my 6048 charger is enabled and set to 2-stage, my MPPT-60 is set to 3-stage with a recharge volt setting of 53.0V (is this optimum?). My grid support voltage is set to 52.5 with Sell enabled (no load shaving). I thought that the Grid Support Voltage had to be lower than the MPPT-60 recharge volt setting in order to sell to the grid, but that contradicts your quote which says Grid Support Voltage needs to be above the "float" setting. Under "Sell" mode, the operation manual states: "When Sell is set to enabled, the Xantrex XW Series Inverter/Charger AC output is divided between powering loads and delivering power to the utility grid. Sell mode requires the battery voltage to be above Grid Supp Volts...The renewable energy from the battery is exported to the grid as long as the battery voltage is greater than or equal to Grid Supp Volts."

    How does this tie in with your comment about this allowing the charge controller to regulate the PV current?

    One final question: Since I have such a small battery bank, is there any efficiency (or battery life) benefit by keeping the 6048 AC OUT in bypass (as configured in the Midnight Solar E-panel), thus sending out all the PV output to the grid via AC1 instead of powering loads through the subpanel? I realize that I lose the battery backup benefit by doing this, but I don't know if the 6048 is more efficient when it doesn't have to balance AC1 grid output with local AC OUT loads.

    As always, thank you for your advice! 8)


    For Selling, "Sell" mode needs to be enabled and Grid Support Voltage needs to be set above the charge controller's float setting or else the charge controller will regulate the PV current while you want it to be sending everything to the grid.

    No solutions offered here but I hope this helps.
    XW6048, 3.4KW PV, Grid-Tied, always tweaking.
  • RCinFLARCinFLA Posts: 1,280Solar Expert ✭✭✭
    Re: Xantrex XW6048 configuration help

    You might read my comments on post "Grid support Xantrex XW4024 Help" April 27th, 2011, post #22, on third page.

    I also think you have a variable which is the state of charge of your batteries. Even if they are fully charged there is some power that will get pushed to them to maintain float or perhaps take them higher into absorb voltage range depending on functional transition states. If you have a large AH battery bank you could possibly consume 150 watts (about 2.8 amps into battery array) for floating consumption. When you add on the parallel PV controller things get more complicated on what is going to inverter or batteries.

    Just to add, the XW does not have direct D.C. battery current sensing. DC current is 'back calculated' by computer taking AC current flows, AC voltages, DC battery voltage and estimated efficiency of inverter conversion.

    I have not actually observed the short grid push but I would not be surprised if it happens as normal grid voltage fluxuation must be sensed and adjusted which take a short amount of time. If the grid voltage drops suddenly, perhaps due to a neighbor's air conditioner kicking on, the XW will be matched the old grid voltage and as result will momentarily push power to grid (as it was tracking the higher grid voltage) as it senses and readjusts to match the new lower grid voltage. The UL1741 specs allow for short pushes to grid without being considered selling to grid.
  • BB.BB. Posts: 28,079Super Moderators, Administrators admin
    Re: Xantrex XW6048 configuration help

    Here is the Post RC is referring too (and a link back to the thread):
    RCinFLA wrote: »
    Before I start, I would like to say I think the XW inverters are pretty good units.

    Having said that, I think the XW is an example of software designers run amuck. Naming conventions and interaction between functions make setup very confusing.

    The op's manual is absolutely horrible.

    If you start with an understanding of the basic hardware functionality it can help understand the mutated explainations in the op's manual.

    Refer to the simpified attached diagram during following descriptions.

    The XW inverter is a bi-directional inverter. This means the inverter can push or pull power to or from the batteries. It has a large transformer that has a high frequency pulse width modulated MOSFET H-bridge driving the primary side at battery voltage and a center tapped secondary winding for the 240 vac output. (actually two individual 120 vac secondary winding configured in series).

    The high frequency PWM creates the 60 Hz sinewave and regulates the voltage level and phase of the inverter. The difference between pushing or pulling power to the batteries is just a slight modification to the PWM signal creating the voltage level of the 60 Hz sinewave output. It can move from charging to supplying ACout on the fly.

    The filtered sinewave output of the inverter is hard wired to the ACout node connection. There are 60 amp rated power relays on the AC1in and AC2in that connect one of the two ACin's to the ACout output node.

    There are voltage senses on ACin connections, a common ACin current sense after the power relays, and voltage and current senses on the inverter output. The senses are all AC vector capable meaning they can be used to check voltage and phase match between ACin port and Inverter/ACout port. This also allows absolute power and power factor calculations.

    With these voltage and current senses the computer can calculate and control the power flow directions on any of the ports.

    Before either of the two power relays are engaged, the inverter voltage and phase must be slewed to match the ACin (blinking green LED). Once it does, the relay closes and inverter is running in parallel with the ACin (green LED turns solid).

    Beyond this basic hardware, everything else is purely software.

    I read and re-read the op's manual to try and understand what 'Grid Support Enable' means. I have concluded that it only means that if it is NOT enabled, the inverter is not allowed to push out power from batteries to ACout node. When it is not enabled the inverter can only charge the batteries while connected to grid. Again this is only slight PWM control on primary side to prevent inverter from pushing out power based on the vector multiplication of the current and voltage sense measurements on the inverter output connection. The PWM has to be constantly adjusted to prevent inverter from pushing out power as the battery voltage and line voltage varies.

    The inverter power outputting seems to have three modes while inverter is running in parallel with ACin (inverter syncronized and power relay engaged).

    1) Grid Support Enabled, Sell disable, Load Shave disabled. - Inverter will push power to ACout node if battery voltage goes above Grid Support voltage setting. There are other interactive conditions to this. Obviously if battery is going through its first and second phase of charging it won't be pushing power out. Being that Sell is not enabled, any pushed power to ACout node must be consumed by ACout load. No power will be allowed to go back up AC1in port. If ACout load cannot consume the pushed power then the battery voltage will be allowed to rise. Presumably the PV controller will take over the regulation and prevent battery voltage from continue rising.

    2) Grid Support Enabled, Sell disabled, Load Shave enabled. - Exactly like above with the difference being inverter will be allowed to push power at lower battery voltage, down to 2 volts above LBCO setting.

    3) Grid Support Enabled, Sell Enabled, Load Shave Disabled. - Just like like 1) with allowance of any excess pushed power (beyond consumed by ACout load) to exit out AC1in port to grid. Range of battery voltage is active at Grid Support voltage, deactivate at Grid Support voltage - 0.5 vdc.

    Keep in mind the inverter AC power output push is continously variable in strength. At Grid Support voltage it just barely starts to push. As battery voltage goes up (just a little) it pushes harder.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • DustyDusty Posts: 271Solar Expert ✭✭✭
    Re: Xantrex XW6048 configuration help

    Thank you! I wasn't having any luck with finding that thread, even though the directions on how to find it were very meticulous.

    -Dusty
    XW6048, 3.4KW PV, Grid-Tied, always tweaking.
  • SolaRevolutionSolaRevolution Posts: 407Solar Expert ✭✭✭✭✭✭
    Re: Xantrex XW6048 configuration help
    Dusty wrote: »
    I'm still testing this setup, but right now my 6048 charger is enabled and set to 2-stage, my MPPT-60 is set to 3-stage with a recharge volt setting of 53.0V (is this optimum?). My grid support voltage is set to 52.5 with Sell enabled (no load shaving). I thought that the Grid Support Voltage had to be lower than the MPPT-60 recharge volt setting in order to sell to the grid, but that contradicts your quote which says Grid Support Voltage needs to be above the "float" setting. Under "Sell" mode, the operation manual states: "When Sell is set to enabled, the Xantrex XW Series Inverter/Charger AC output is divided between powering loads and delivering power to the utility grid. Sell mode requires the battery voltage to be above Grid Supp Volts...The renewable energy from the battery is exported to the grid as long as the battery voltage is greater than or equal to Grid Supp Volts."

    How does this tie in with your comment about this allowing the charge controller to regulate the PV current?

    Dusty,

    An issue that I was pointing out is that the Charge Controller (XWMPPT60-150) and the inverter (XW6048 ) have temperature compensation for battery charging but the "Sell" voltage (Grid Support Voltage) setting does not. I'm not sure if there is a network function which prevents the CC from regulating current while the inverter is supposed to be selling. If you are not "selling", the non-temp-compensated "Grid Support Voltage" setting can still affect the current flow within your system.

    For example: If your temp-comp-float voltage setting of your charge controller is lower than your actual (non-temp comp) "grid support voltage", the solar charge controller could be preventing you to use the solar current because the voltage setting which controlls the inverter's mechanism which allows current from the battery bus to be used to power AC loads may be higher than the solar charge controller's "target" voltage.

    Clear as mud?:blush:

    Once again, there may be a network function in one or more of the firmware versions that deals with this but it is not mentioned in any of the manuals that I know of.

    This sort of issue is much more likely to be a problem when you have a system with different brands of equipment because they do not share temp-comp or battery voltage information.

    Alex Aragon
  • DustyDusty Posts: 271Solar Expert ✭✭✭
    Re: Xantrex XW6048 configuration help

    Yup, clear as mud.... :confused:

    Now that I was told how to set up Enhanced Interactive Mode (no thanks to the operations guide), my GSV is set to 64V on the 6048, and it seems to be selling with no issues. Thankfully, all the gear is Xantrex and networked. I just with the operations manual was written better to include all the functionality of the hardware. I'm not sure how they get away with leaving so much out of the manual. Someone should write a book to augment the op manual.

    My battery bank (AGM) is indoors and not subject to extreme heat or cold. The BTS is installed to prevent thermal runaway. So, hopefully I won't get into the situation where the temp-comp-float setting is lower than the GSV.

    Thank you!

    -Dusty
    Dusty,

    An issue that I was pointing out is that the Charge Controller (XWMPPT60-150) and the inverter (XW6048 ) have temperature compensation for battery charging but the "Sell" voltage (Grid Support Voltage) setting does not. I'm not sure if there is a network function which prevents the CC from regulating current while the inverter is supposed to be selling. If you are not "selling", the non-temp-compensated "Grid Support Voltage" setting can still affect the current flow within your system.

    For example: If your temp-comp-float voltage setting of your charge controller is lower than your actual (non-temp comp) "grid support voltage", the solar charge controller could be preventing you to use the solar current because the voltage setting which controlls the inverter's mechanism which allows current from the battery bus to be used to power AC loads may be higher than the solar charge controller's "target" voltage.

    Clear as mud?:blush:

    Once again, there may be a network function in one or more of the firmware versions that deals with this but it is not mentioned in any of the manuals that I know of.

    This sort of issue is much more likely to be a problem when you have a system with different brands of equipment because they do not share temp-comp or battery voltage information.

    Alex Aragon
    XW6048, 3.4KW PV, Grid-Tied, always tweaking.
  • SolaRevolutionSolaRevolution Posts: 407Solar Expert ✭✭✭✭✭✭
    Re: Xantrex XW6048 configuration help
    Dusty wrote: »
    I just with the operations manual was written better to include all the functionality of the hardware. I'm not sure how they get away with leaving so much out of the manual. Someone should write a book to augment the op manual.
    -Dusty

    I could be mistaken, but I think I remember hearing an equipment manufacturer explain that the manuals are required to go through the underwriter listing process but the firmware revisions are not. New firmware is often accompanied by tech notes to help explain the changes. Some manufacturers are constantly upgrading and their manuals just do not keep up. On the one hand, it's great that they are constantly improving the functionality of the gear. On the other hand, it's hard to keep track of what version is capable of what.

    I don't think I saw a bound version of the Outback MX60's manual until it had been out for several years. The original XW manual was out of date when I was installing serial number +/-200. I still often call tech support when I replace an inverter or add a new one to an existing system just to try to make sure there will not be any major operational or incompatability issues when mixing old and new equipment. Schneider recommends that you upgrade all equipment to the latest firmware when changing out or adding new gear. Outback requests that you set the newest inverter as the master when using multiple inverters of different ages.

    Alex
  • SikiruSikiru Posts: 1Registered Users, Users Awaiting Email Confirmation
    Hi all 

    i need help configuring snmp for xantrex xw6048
  • mike95490mike95490 Posts: 7,967Solar Expert ✭✭✭✭
    Sikiru said:
    Hi all 

    i need help configuring snmp for xantrex xw6048
    The  xantrex xw6048 has XANBUS  connector, needing terminations at both ends, it is not ethernet, and may have 24+ VDC on some of the wires to power downstream devices.
    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 ,

Sign In or Register to comment.