n2aws
Solar Addict
- Joined
- Oct 24, 2022
- Messages
- 687
Supposedly, the 64V setting only matters in voltage based usage. However, I've found that even in SOC mode (closed loop) it matters. if you set it to 64V with SOC, it never actually sells back.
Schneider XW Pro Enhanced Grid Support issues
- Thread starter romangeek
- Start date
Philip53
10.4kw DIY Home Solar Sprinter Van DIY Victron
- Joined
- Aug 22, 2022
- Messages
- 103
Just FYI: I have a 12 year old XW6048 that I have run on 64v sell setting for most all of those years. It sold back to the grid w/o problems. A few months ago, I changed out the original Concorde AGM's with Trophy lithiums, and have been experimenting with the sell voltage. I did try the 64v setting, but it set off a high voltage alarm, which shut down one of the batteries, but it reset shortly thereafter. I currently have the sell voltage at 53.4. This keeps the battery between 85-90% SOC, even though the BMS's, given several days will show 95-99%.
400bird
Solar Wizard
Considering you've posted on 3 different Schneider threads, I assume you ba e some issue? If you describe the issue, maybe you'll get some help.
I have XW 6848pro recently entered the program to sell to the grid... I have tried to make adjustments based on the manual and what technical support tells me but I always see that the inverter draws a lot of amperage from the batteries. I have seen that some here have had this problem and I would like you to give me a guide on how to solve it...I currently have it in Enhanced Grid Support 64V........thanks
400bird
Solar Wizard
What charges your battery?
Two CC Schneider 60/150....5.9K in pv
400bird
Solar Wizard
Ok, and what specifically are you looking for the inverter to do?
RCinFLA
Solar Wizard
- Joined
- Jun 21, 2020
- Messages
- 3,566
CT transformers have accuracy and tolerance in their reported current and its phase relative to AC voltage (need phase info to know if current is going in or out AC input port). A safety margin is usually held by inverter when no-selling is selected that prevent supplementing AC input for AC input currents less than about 4-5 amps No supplementing of AC input will occur when grid AC input feed drops below 4-5 amps of incoming current from grid. This is to ensure CT accuracy does result in some continuous grid back feed. Victron inverter will not let you set AC input assists level trigger to less than 5 amps.
Inverter has some response time to react to load shaving and grid voltage fluctuations. If grid voltage suddenly dips a bit there will a little back feed until inverter readjusts inverter output to the grid voltage fluctuation.
These slight, short time period grid back feed leaks will not trigger a smart meter report for back feeding. A water pump motor will back feed grid during a portion of AC cycle due to its inductive load power factor and can also momentarily back feed when there is a momentary grid voltage dip.
Possible poor power factor of AC loads makes AC power input or output flow determination a bit more complicated. Because a poor reactive power factor load will have positive and negative AC current flow during portions of the AC cycle, the inverter must time average the calculated power to determine net power flow direction. This slows down response time.
On initial AC input connect, the inverter has pass-through relay open. It adjusts inverter to match AC input voltage it measures on AC input side of pass-through relay and slowly slews inverter frequency/phase to match that of AC input. This is done open loop based on factory calibration of frequency/phase measurement. If phase calibration is off, when it thinks everything is aligned and closes pass-through relay there will some current surge from slightly misaligned phase. The inverter should do a fine phase alignment adjustment to minimize the phase misalignment by current sensing.
Frequency/phase alignment is done slowly so not to perturb any AC out loads, like a refrigerator or water pump AC motor. This requires the AC input source to be fairly phase stable or the inverter will not be able to track AC input phase wobble. This is a common issue with fixed rpm synchronous generators when the generator's AC output freq/phase is wobbling due to an unstable rpm governor control.
When connected to a synchronous generator and a sudden AC out surge load occurs, some of the surge is supplied by inverter and some of the surge is supplied by generator. If the synchronous generator bogs down from the surge load and drops engine rpm it also shifts its output frequency. If this freq/phase shift is too fast, the inverter phase tracking being limited in reaction time, will not be able to follow the generator phase shift. This may cause inverter to release from generator because of current surges due to phase misalignment.
When an inverter has AC input load shaving it can take up more of AC out load preventing generator overload. The inverter has some reaction time for sudden load surge current so for a few milliseconds some of the surge may leak through to AC input.
Victron's 'dynamic' AC input load shaving starts the load shaving earlier than user set AC input current limit when the increase rate of load current is high, like on an AC motor surge current during startup. After current stabilizes, the inverter backs down its supplementing if stable current is less than user set load shaving limit. The is supposed to give the Victron inverter a jump on handling surge loads preventing generator overload.
Inverter has some response time to react to load shaving and grid voltage fluctuations. If grid voltage suddenly dips a bit there will a little back feed until inverter readjusts inverter output to the grid voltage fluctuation.
These slight, short time period grid back feed leaks will not trigger a smart meter report for back feeding. A water pump motor will back feed grid during a portion of AC cycle due to its inductive load power factor and can also momentarily back feed when there is a momentary grid voltage dip.
Possible poor power factor of AC loads makes AC power input or output flow determination a bit more complicated. Because a poor reactive power factor load will have positive and negative AC current flow during portions of the AC cycle, the inverter must time average the calculated power to determine net power flow direction. This slows down response time.
On initial AC input connect, the inverter has pass-through relay open. It adjusts inverter to match AC input voltage it measures on AC input side of pass-through relay and slowly slews inverter frequency/phase to match that of AC input. This is done open loop based on factory calibration of frequency/phase measurement. If phase calibration is off, when it thinks everything is aligned and closes pass-through relay there will some current surge from slightly misaligned phase. The inverter should do a fine phase alignment adjustment to minimize the phase misalignment by current sensing.
Frequency/phase alignment is done slowly so not to perturb any AC out loads, like a refrigerator or water pump AC motor. This requires the AC input source to be fairly phase stable or the inverter will not be able to track AC input phase wobble. This is a common issue with fixed rpm synchronous generators when the generator's AC output freq/phase is wobbling due to an unstable rpm governor control.
When connected to a synchronous generator and a sudden AC out surge load occurs, some of the surge is supplied by inverter and some of the surge is supplied by generator. If the synchronous generator bogs down from the surge load and drops engine rpm it also shifts its output frequency. If this freq/phase shift is too fast, the inverter phase tracking being limited in reaction time, will not be able to follow the generator phase shift. This may cause inverter to release from generator because of current surges due to phase misalignment.
When an inverter has AC input load shaving it can take up more of AC out load preventing generator overload. The inverter has some reaction time for sudden load surge current so for a few milliseconds some of the surge may leak through to AC input.
Victron's 'dynamic' AC input load shaving starts the load shaving earlier than user set AC input current limit when the increase rate of load current is high, like on an AC motor surge current during startup. After current stabilizes, the inverter backs down its supplementing if stable current is less than user set load shaving limit. The is supposed to give the Victron inverter a jump on handling surge loads preventing generator overload.
Last edited:
That when I sell to the grid I don't draw amperage from my batteries
RCinFLA
Solar Wizard
- Joined
- Jun 21, 2020
- Messages
- 3,566
DC coupling PV to batteries then using inverter to sell AC power to grid always puts 120 Hz ripple current on batteries. The peak-to-peak ripple current is twice the average inverter DC current, 120 Hz AC sinewave current centered on average DC current is swinging from near zero to twice the average current.
Even when there is no net average current into or out of battery, the large ripple current stresses and creates heating of battery due to battery's internal impedance.
The batteries are effectively a large filter capacitor to take the PV illuminated based constant current PV feed to the sine square power profile of single-phase AC power.
Last edited:
400bird
Solar Wizard
The short version is set the grid support voltage higher than battery voltage.
Edit to add that the MPPT much have charge settings that are higher than grid support voltage.
The inverter will sell any energy it can get that is above the grid support voltage setting. If you enable grid support when the battery is above that setting, the inverter will dump that to the grid. Try enabling/adjusting grid support in the morning when battery voltage is lower.
Longer versions involve requests to see all your settings.
Thank ... I'll follow those recommendations and then I'll let you know
Thank You!
After recent 1.17 Insight upgrade, inverters began switching between "AC passthrough" and "Grid support" at low usage time of day (sunset)
Inverter status just toggles back and forth between the two.
I changed the MPPT "Float voltage set point from 54.0 to 54.5, toggling ceased!
Grid suport voltage is 54.0.
(FLA batteries)
Note - no sell back, grid use is for load support when PV is not available.
Hamish
New Member
I have more than 25 hours into this problem. Thank you so very much for giving me the "key."
Hamish
New Member
I and my installer have wasted a lot more than 25 hours over the last 3 months. I tried the 64 volt trick and of course it did not work. I tried setting grid support voltage to the floater voltage voltage and that did not work. I have a whole list of " tricks" from various manuals and blogs, some of which seem magical and others that seem reasonable but do not work. Nothing seems to work. I am beginning to think there's a fundamental flaw in the latest firmware. For my next trick, I plan on shutting everything down, disconnecting all power, and leaving it to cook overnight. Then I will reboot all the components one by one to factory defaults. Then I will go through and correct those parameters that aren't right.
Of course it would be nice to be able to save and reload parameter sets, but when I try to upload a previously downloaded configuration, it hangs my Chrome browser. I am not surprised. I am reduced to opening all the tabs and then printing that page. I can then go back and reset all the parameters, one by one, tedious, and not helping my current frame of mind.
My xw Pro and batteries are new. But now I am researching other products like Outback. LOL.
n2aws
Solar Addict
- Joined
- Oct 24, 2022
- Messages
- 687
I've heard other forums post that resetting the inverter to factory defaults, and re-configuring it solved odd "gremlins". I've never needed to do it myself, but just throwing it out there.
Hamish
New Member
I did the full shutdown and factory reset procedure. The system is now running but continues to draw power from the battery when the solar panels are producing more than enough. Enhanced grid support should not be doing that. My system is intended as a backup system and should only draw power from the battery if the grid and solar are not sufficient.
n2aws
Solar Addict
- Joined
- Oct 24, 2022
- Messages
- 687
One sec, I want to make sure I'm not misunderstanding.
You want the batteries to stay nearly 100% most of the time, you are able to sell to grid (ie, you have a net metering agreement). and don't want it drawing from the battery unless it's a grid outage, correct?
If so, I'd do this:
- Enable grid sell (under inverter > configuration > control)
- Enable grid support (Inverter > configuration > grid energy management > grid support > enable
Under grid support, also set:
- Set Grid Support voltage to 67v
- Grid support SOC to 100%
- Grid sell amps to max
- Grid peak load shave enabled
- Load shave amps to 0
Make sure your MPPT's are set to 3 stage.
When your batteries are fully charged and the mppts switch to float mode, the generated power will be sold to the grid. And it shouldn't consume battery unless there is a power outage.
Please know that the above assumes insigh firmware 1.18b41. and XW Pro firmware 2.04b29
If the batteries are below 100% SOC, it'll prioritize recharging the batteries over supporting loads or selling to the grid
BentleyJ
Solar Wizard
Load Shave Amps is the value used to determine when the inverter starts to supplement loads using battery power. So If it is set to 0 then NO current will be drawn from the grid and the inverter will try and satisfy all loads from the batteries. This is exactly the opposite of what Hamish is wanting to do.
JBertok
Network Engineer
It sound like the XWs are holding the DC voltage higher than the MPPTs are, and the MPPTs are tapering off.
They're not watching the Charge Controllers as expected.
Can you verify the absorption and float setpoints are identical between the MPPT 100 600 and the XW Pro.
If it was working right the XW Pro should be holding the DC voltage just a bit below what the MPPTs are trying to push it to though the entire 3=stage charging sequence, with an exception that if there is a sudden 2V increase it could disrupt it.
They're not watching the Charge Controllers as expected.
Can you verify the absorption and float setpoints are identical between the MPPT 100 600 and the XW Pro.
If it was working right the XW Pro should be holding the DC voltage just a bit below what the MPPTs are trying to push it to though the entire 3=stage charging sequence, with an exception that if there is a sudden 2V increase it could disrupt it.
