Conext SW4048 AC Couple Smart Charge

[MisterSandals]

Hello Community

I have been messing with this for a few weeks and am stumped about the "AC Couple Smart Charge" feature. It works as written in that it will take AC micro inverter power and charge batteries first and then pass thru the rest to the grid. I turn this feature on with the "AC Coupling" control enabled.

 The problem that I am having is figuring out how to USE the battery without inadvertently disabling the "AC Couple Smart Charge" feature.

I see 2 ways to configure to use the battery power:
1) "AC Support Mode Enable" enabled
Uses battery power to "support" my critical loads panel by some unknown amount/metric as long as battery voltage is above the "AC Support Voltage" (set to 52V).

Enabling this disables the AC Couple Smart Charge feature (meaning it stops charging the batteries from my micro inverters/critial loads panel).

 2) "Peak Load Shaving Enable" enabled
Uses battery power to "support" my critical loads panel (above set number of AC amps, 1A, the minimum value, in my case) as long as battery voltage is above the "AC Support Voltage" (set to 52V).

Enabling this also disables the AC Couple Smart Charge feature (meaning it stops charging the batteries from my micro inverters/critial loads panel). I can turn off Peak Load Shave with the start and stop settings for the period I expect my micro inverters to be producing an excess over the critical loads panel use. I can set it for 11AM stop when my array is currently in full sun and to start at 4PM when the sun currently goes behind trees. This "currently" works but would need to be adjusted continually to maximize excess power. Controlling this "smart" feature manually in such a way seems wrong and inconvenient.

I spent the last couple weeks trying different features and different combinations without any success in finding a good solution. I know i could use node-red to toggle either of these features as excess power is sensed. Why would a "smart" feature to charge batteries prohibit using the batteries without intervention?

I can provide other settings upon request.

thanks or and ideas or snarky comments if i deserve them

[MisterSandals]

And nothing here?

Or here:

Thank you for contacting Schneider Electric.
Your question has been received. You should expect a response from us within the next business day.

Case Reference #: 106410379

[MisterSandals]

One week on, no response.  Turns out case inexplicably closed.

New case 9jan24

Case Reference #: 106563213

Narrowed scope of the bug down to AC Coupling Mode when enabled, completely disables AC Coupling Smart Charge.

Doc says "

AC Couple Smart Charge is a feature of the Conext SW that prioritizes battery charging over energy export to local AC loads connected upstream of the Conext CSW battery inverter. AC Coupling must be enabled for this feature to be functional."

My system is behaving exactly the opposite.  AC coupled excess power passed thru to grid, always, when AC Couple Mode enabled.  

Disabling  AC Couple Mode charges the batteries perfectly (though it does not start a bulk charge cycle as the docs indicate).

[MisterSandals]

Here is my config file contents.  Sorry for the form, i could not attach .json, .rft, .txt or .zip

{"1":{"type":"SYS","groups":{}},"2":{"type":"SYS","groups":{}},"255":{"type":"MBSYS1","groups":{}},"1672098":{"type":"CSW","groups":{"Controls":[{"name":"Inverter Enable/Disable","value":"Enabled"},{"name":"Charger Enable/Disable","value":"Enabled"},{"name":"Force Charger State","value":""},{"name":"Operating Mode","value":"Operating"},{"name":"Reset","value":"Reboot"},{"name":"Clear","value":""}],"AC Support":[{"name":"AC Support Voltage","units":"V","value":51.8},{"name":"Load Shave Stop","units":"min","value":"2024-01-09T19:00:00.000Z"},{"name":"Load Shave Start","units":"min","value":"2024-01-09T23:45:00.000Z"},{"name":"Peak Load Shaving Delay","value":"Disabled"},{"name":"Peak Load Shaving Enable","value":"Disabled"},{"name":"AC Support Mode Enable","value":"Enabled"},{"name":"Peak Load Shaving Current","units":"A","value":1},{"name":"State of Charge Level to Start AC Support","units":"%","value":70},{"name":"State of Charge Level to Stop AC Support","units":"%","value":20},{"name":"Time Delay to Enter AC Support on SOC","units":"s","value":10},{"name":"Time Delay to Exit AC Support on SOC","units":"s","value":10}],"Charger Settings":[{"name":"Charge Cycle","value":"2 Stage"},{"name":"Maximum Charge Rate","units":"%","value":60},{"name":"Equalize Now","value":"Disabled"},{"name":"Charger Override Enable/Disable","value":"Disabled"},{"name":"Default Battery Temperature","value":"Warm"},{"name":"Equalize Voltage Set Point","units":"V","value":64},{"name":"Equalize Support","value":"Equalization Not Allowed"},{"name":"Bulk/Boost Voltage Set Point","units":"V","value":55.8},{"name":"Maximum Bulk Charge Current","units":"A","value":45},{"name":"Bulk Termination Voltage","units":"V","value":55},{"name":"Bulk Termination Time","units":"s","value":180},{"name":"Absorption Voltage Set Point","units":"V","value":55.5},{"name":"Maximum Absorption Charge Current","units":"A","value":45},{"name":"Absorption Time","units":"min","value":180},{"name":"Float Voltage Set Point","units":"V","value":54},{"name":"Maximum Float Charge Current","units":"A","value":45},{"name":"Charge Block Start","units":"min","value":"2024-01-09T14:00:00.000Z"},{"name":"Charge Block Stop","units":"min","value":"2024-01-09T14:05:00.000Z"}],"Inverter Settings":[{"name":"Search Mode","value":"Disabled"},{"name":"Inverter Mode","value":"Split Phase Primary"},{"name":"Maximum Search Watts","units":"W","value":50},{"name":"Search Delay","units":"s","value":5},{"name":"Invert Block Start","units":"min","value":"2024-01-09T08:00:00.000Z"},{"name":"Invert Block Stop","units":"min","value":"2024-01-09T08:00:00.000Z"},{"name":"European Frequency","value":"Disabled"},{"name":"Store Invert State","value":"Enabled"},{"name":"AC Coupling","value":"Enabled"},{"name":"Enhanced AC Support","value":"Disabled"},{"name":"No Load Voltage Derating","value":"Disabled"}],"Advanced Device Settings":[{"name":"Periodic Transmit Enable","value":"Enabled"},{"name":"Identify Enable","value":"Disabled"}],"Modbus Settings":[{"name":"Modbus Server Address (Port 502)","value":0},{"name":"Modbus Server Address (Port 503)","value":90}],"Battery Management System Settings":[{"name":"Maximum Discharge Current","units":"A","value":150},{"name":"Maximum Discharge Time Interval","units":"s","value":10}],"AC Settings":[{"name":"AC1 Breaker Size","units":"A","value":30},{"name":"AC1 Low Voltage","units":"V","value":95},{"name":"AC Qualify Time","units":"s","value":10},{"name":"AC1 High Voltage","units":"V","value":135},{"name":"AC1 Low Frequency","units":"Hz","value":55},{"name":"AC1 High Frequency","units":"Hz","value":65}],"Battery Settings":[{"name":"Battery Type","value":"Custom"},{"name":"Battery Bank Capacity","units":"Ah","value":550},{"name":"Battery Temperature Coefficient","units":"mV/degC","value":-108},{"name":"Recharge Voltage","units":"V","value":49},{"name":"Low Battery Cut Out","units":"V","value":48},{"name":"Low Battery Cut Out Delay","units":"s","value":10},{"name":"Low Battery Cut Out Hysteresis","units":"V","value":2},{"name":"High Battery Cut Out","units":"V","value":60},{"name":"AC Support on Battery SOC Enable","value":"Disabled"}],"Associations":[{"name":"AC Output Association (Loads)","value":"AC Load 1"},{"name":"AC Input Association ( Generator )","value":"Grid 1"},{"name":"DC Association (Battery)","value":"House Battery Bank 1"}],"Device Instance":[{"name":"Device Name","value":"CSW4048"},{"name":"Device Number","value":0},{"name":"System Instance","value":0}]}}}

[MisterSandals]

Attaching screenshot of excess AC coupled solar being passed thru to grid with AC Coupling enabled (supposed to charge batteries as AC Coupling Smart Charge).  1:03pm.

[MisterSandals]

Screenshot moments after turning AC Coupling to disable.  Excess AC Coupled solar charging batteries.

1:04pm

AC Coupling "enabled" supposed to be necessary to turn AC Coupling Smart Charge on.  The behavior is the exact opposite from what is described in the SW and AC Coupling docs.

This backwards implementation makes charging and using your batteries, with a single configuration impossible.  

[MisterSandals]

Adding more info document some further steps that i have taken with customer support.

With AC Support Mode enabled, power into the AC Output continues to be passed thru to grid without charging batteries (contradicts AC Coupling Smart Charge feature). I am currently turning the AC Support Mode off from 11am to 4pm manually, everyday to charge my batteries with my AC Coupled solar (very inconvenient, an obvious bug from what i can tell).

On thursday, support suggested that the AC Support Voltage of 51.8V  (battery voltage currently 52.5V) needs to be HIGHER than battery voltage for AC Smart Charge to work.

So, after setting AC Support Voltage to 54.5V, the SW did charge the battery. In hindsight, i believe that this is because the AC Support works as long as battery voltage is higher than the support voltage threshold (the AC Support Voltage description mostly hints that this in a minimum threshold for AC Support, but vague).   And, with AC Support "disabled" because battery voltage lower than this threshold, it behaves the same as turning AC Support Mode off.

Additionally, when power into AC Output stops (sundown), the AC Support remains off and the inverter never starts using the batteries to support AC.

Subsequent conversations with support have told me that the AC Support voltage is the low threshold: battery will not be used if below support voltage setting.  This makes the most sense and is EXACTLY what the documentation says:

>>

Regular AC Support without Xanbus devices

If no Xanbus-enabled devices, such as an MPPT charge controller, are connected to the power system, then entry and exit into AC support mode is based solely on battery voltage monitored by Conext SW. If the battery voltage is above a set limit (AC Supp Volts), then AC support mode is engaged.

>>

So, back to square one after testing based on support's misunderstanding of AC Support Voltage.

I am still convinced this is a software bug.  There is no reason that i can imagine why the software would be designed to prevent charging batteries from AC Coupling (AC Coupling Smart Charge!) AS WELL AS later allowing AC Support using battery power, without changing configurations.

Several support personnel have seen my settings as well as connected to my system.  All have indicated my settings are correct (except for the incorrect info about AC Support Voltage).

[MisterSandals]

I found this terrific document.  It describes perfectly how the AC Couple Smart Charge is supposed to work.

See pages 28 and 29:  Benefitts of SW Smart Charge Feature

https://solar.se.com/au/wp-content/uploads/sites/3/2021/11/Solar-Installer-Handbook_Australia.pdf

And this smart charge feature (always on, built in feature) has a glitch that disables charging when AC Support Mode is enabled.

But all this is beyond the comprehension of the solar tech support staff.  I've shown this to several while they were connected to my SW 4048.  We agree its a bug and i am told it will be "escalated" and i am hurriedly brushed off the call.

This bug is 6 years old from the first instance i found online.  I'm sure its been escalated and worked on for hundreds of hours without being actually passed on to someone who can fix it.

If anybody reading this knows how to get a software bug fixed, circumventing the technical support dead end roadblocks, please do so or let me know how to proceed.

[MisterSandals]

Just wanted to post more info to document this issue.  I received a response from Rhodes Carter the L3 tech handling this.

>>

Rhodes Carter	Thu, Jan 18, 12:04 PM
to me

Sorry for the frustration you're experiencing. I was able to do some testing and located a bug in the Insight Home firmware where it is not correctly reading & writing the AC Coupled Enable setpoint on the SW inverter. Even though you can Enable AC Coupling in IS Local, the setpoint is still set to disabled in the inverter. If you have an SCP you can enable the setting that way and the feature should work as expected. I'm reporting this issue to engineering, and we should have it corrected in a future update. I can't provide a timeframe for this update unfortunately. 

Can you please tell me what FW version you are running on both your SW inverter and the IS Home? Engineering will want to know this for their research.

Please let us know if you have any additional questions. 

Rhodes Carter – Schneider Electric L3 Solar Tech Support | 1-833-391-8640 | SolarSupport-NAM@Schneider-Electric.com

[MisterSandals]

Is this thread still locked and censored?  Why weren't my updates posted?  This is a real software issue that needs to be fixed.