n2aws
Solar Addict
- Joined
- Oct 24, 2022
- Messages
- 690
Nice function, but.. if you are looking at the official documentation rom Schnieder, it includes the hex and dec addresses
Schneider XW Pro rant: AC1 Charging and AC Passthrough
- Thread starter rfsam
- Start date
Nice function, but.. if you are looking at the official documentation rom Schnieder, it includes the hex and dec addresses
400bird
Solar Wizard
I was wondering what used hex in this modbus set up...
I guess I learned to look past the hex and go straight to the decimal column.
I guess I learned to look past the hex and go straight to the decimal column.
ah..multiple docs - was looking at another, 1 does not have the dec code. With this doc -1 as per your writeup...cool
few more questions..
- I have my batteries(eg4) set to 3 cycle charging but I am not using SOC so how does it know when to stop bulk charging? The voltages are based on eg4 doc (56.2 for bulk/absorb, 54v for float). The voltages never get to these values. SOC gets to 100 before voltages. Should I switch them to 2 cycle - default? I think the 60A breaker tripped yesterday with this error but my HBCO is at 58. Not sure how it tripped
Cause: Battery voltage is (BattV), which is approaching the High Battery Cut Out level of (HBCO). Solution: Check battery cables. Check for the correct battery voltage at the inverter's DC input terminals. Make sure the DC source is regulated below the high battery cut out or increase the High Batt Cut Out setting.
What values do you guys have in the battery section?
- I have my batteries(eg4) set to 3 cycle charging but I am not using SOC so how does it know when to stop bulk charging? The voltages are based on eg4 doc (56.2 for bulk/absorb, 54v for float). The voltages never get to these values. SOC gets to 100 before voltages. Should I switch them to 2 cycle - default? I think the 60A breaker tripped yesterday with this error but my HBCO is at 58. Not sure how it tripped
Cause: Battery voltage is (BattV), which is approaching the High Battery Cut Out level of (HBCO). Solution: Check battery cables. Check for the correct battery voltage at the inverter's DC input terminals. Make sure the DC source is regulated below the high battery cut out or increase the High Batt Cut Out setting.
What values do you guys have in the battery section?
400bird
Solar Wizard
Do you have BMS communication set up? If so the BMS is dictating the charge cycle.
60 amp AC breaker? I'm not sure the alarm is related.
I've posted here before, this is the "warning" alarm that sets 3 volts below your HBCO to give some warning that the voltage is getting high. I really wish they'd include that info somewhere.
At least, they improved the fault text, it used to say 68 volts!
So when this happened, the charge cycle was set to External BMS as I do have closed loop communications but have not used SOC yet. I then changed it to 3 cycle. On 3 cycle, it kept on charging till 98% before I turned it off as I did not want it to trip. I received 4 alarms with External BMS set. I thought maybe the first one as the issue. Here are the 4 alarms
ah..maybe the first event in my image...approaching HBCO..but there is no time difference between that event and other events
n2aws
Solar Addict
- Joined
- Oct 24, 2022
- Messages
- 690
I've never tried this, so grain of salt:
It is my understanding from the documentation that if you want to use Enhanced Grid Support, the inverter charger needs to be set at 2 stage (and if you have Schnieder charge controllers, those get set to 3 stage). (I don't use the charger built into the inverter, so this is purely an opinion from reading the docs. My suspicion is, if the inverter never leaves "charge" mode, then it can never actually enter invert mode to start selling back excess PV)
Second, If you are using SOC control (and you should, if you have closed loop comms) the BMS will tell the schnieder gear to ramp down it's charge current as the batteries near full. Pure assumption here, but.. make sure your batteries have the latest firmware, so they top balance correctly. When I've seen the "DC Over voltage" when the batteries are nearly full.. it was due to the cells being imbalanced (older battery firmware) and one of the packs would hit a cell overvoltage limit, and the BMS for that pack would stop accepting a charge. For a brief moment, the current that was going to that pack had to go somewhere, so the DC bus saw a massive voltage spike. Thus the alert.
I would break out the BMS utility on your computer, let the batteries charge to 98% or so, and then check cell voltages. Check all the packs for any internal alarms, etc. But also check the firmware, and get them updated if they are older.
It is my understanding from the documentation that if you want to use Enhanced Grid Support, the inverter charger needs to be set at 2 stage (and if you have Schnieder charge controllers, those get set to 3 stage). (I don't use the charger built into the inverter, so this is purely an opinion from reading the docs. My suspicion is, if the inverter never leaves "charge" mode, then it can never actually enter invert mode to start selling back excess PV)
Second, If you are using SOC control (and you should, if you have closed loop comms) the BMS will tell the schnieder gear to ramp down it's charge current as the batteries near full. Pure assumption here, but.. make sure your batteries have the latest firmware, so they top balance correctly. When I've seen the "DC Over voltage" when the batteries are nearly full.. it was due to the cells being imbalanced (older battery firmware) and one of the packs would hit a cell overvoltage limit, and the BMS for that pack would stop accepting a charge. For a brief moment, the current that was going to that pack had to go somewhere, so the DC bus saw a massive voltage spike. Thus the alert.
I would break out the BMS utility on your computer, let the batteries charge to 98% or so, and then check cell voltages. Check all the packs for any internal alarms, etc. But also check the firmware, and get them updated if they are older.
BentleyJ
Solar Wizard
The first 3 events are Faults while the 4th is a Warning.
They do recommend 2 stage when I had talked to them.
soc -- I will get there
Interesting, yeah, that makes sense
I have the latest firmware on batteries and inverter. I will try out some of the things you mentioned.
400bird
Solar Wizard
You never answered which breaker, but seeing the faults, looks like it was a 60 amp AC breaker.
I guess I was wrong and they are related. I'd spend time figuring out what's going on with your loads to trace down why the breaker tripped.
n2aws
Solar Addict
- Joined
- Oct 24, 2022
- Messages
- 690
I missed the part about a breaker tripping.
I'm with 400bird here. breakers tripping is a huge red flag. Figure that out first, before any of the "nice to have" settings.
sorry, yeah, it is the AC1 IN breaker.
External BMS was set. With External BMS, the Max Charge takes effect. If at max (140A) and a single battery, would that trip the breaker?
:-( ok. Will do
400bird
Solar Wizard
Shouldn't trip that breaker as the XW monitors input current and has settings to avoid tripping the AC breakers. It should lower charge current to stay below tripping the breaker.
Also, 60 amps x 240 vac = 14,400 watts
140 amps x 60 vdc = 8,600 watts
But, were you charging from the grid? If not, then the charger isn't putting any current through the AC input breaker.
If you had been running near 60 amps AC for hours, maybe. But, without more data, I'd be more inclined to think some large load started with too much else already running.
n2aws
Solar Addict
- Joined
- Oct 24, 2022
- Messages
- 690
Not unless you also had something like 7,000w of load, in addition to the 140a charging.
140a x 51.2v = 7168w (I went with nominal voltage just to show the math)
60a x 240 = 14,400 watts (again, nominal)
So assuming your wires are properly sized, and the breaker is 60amps.. at "full throttle" charging of the batteries, you still have roughly 7,000 watts available before that AC breaker should trip.
I'm concerned you may have something else going on, other than just settings in the Schnieder stuff. I'd hate to see a shock or fire hazard, so yeah man, focus on that first. Also, I'd strongly encourage you to find the root cause if at all possible. I'm not a big fan of "well, it must have been a 1 time freak thing" with stuff like this. It tripped for a reason. Too much current, too much heat, loose connections causing arcing (if it's an arc-fault breaker), breaker failing/going bad.. etc. *something* caused it to trip.
my charging is always from the grid as I don't have any solar
I only have few circuits which pull in about 300w (tv & lights). The only time it trips is when charging and the current on the inverter shows going up to 70+ amps. I will check my wires though and I have also sent an email to schneider on the loose sleeve on the cable inside the inverter that @n2aws pointed out. I checked and that looks ok as it is only the sleep. Connections seem fine but will need to double check. Thank you
breaker on the main panel and sub-panel is 60A and the wires are 6 awg. Load is around 300w.
yeah, need to go thru it carefully
n2aws
Solar Addict
- Joined
- Oct 24, 2022
- Messages
- 690
n2aws
Solar Addict
- Joined
- Oct 24, 2022
- Messages
- 690
Does your 60a breaker provide power to anything other than the inverter? like maybe a loads panel or something? Any way additional current would be going though that breaker, that *is not* being used directly by the inverter or passthrough?
GXMnow
Solar Wizard
- Joined
- Jul 17, 2020
- Messages
- 2,789
Something is seriously wrong for that 60 amp breaker to trip. Where is this breaker? Is it in the Schneider PDP or is it back in your main panel?
IS the breaker getting hot? I would suspect a bad connection of failing breaker. Do you have a clamp on amp meter? Measure the current at that breaker. Check both legs.
I only have a 20 amp breaker on the input of my XW-Pro because of my 120% rule back to my 100 amp main panel. I have never tripped that breaker.
IS the breaker getting hot? I would suspect a bad connection of failing breaker. Do you have a clamp on amp meter? Measure the current at that breaker. Check both legs.
I only have a 20 amp breaker on the input of my XW-Pro because of my 120% rule back to my 100 amp main panel. I have never tripped that breaker.
no. So the 60A from main panel is dedicated to the inverter. The inverter feeds a sub-panel which also has a 60A breaker
main(60a) --> inverter --> sub-panel(60a)
main(60a) --> inverter with mini-pdp breaker(s) --> sub-panel(60a)
>IS the breaker getting hot? I would suspect a bad connection of failing breaker. Do you have a clamp on amp meter? Measure the current at that breaker. Check both legs.
ok. Will check it out
>I only have a 20 amp breaker on the input of my XW-Pro because of my 120% rule back to my 100 amp main panel. I have never tripped that breaker.
Interesting. My plan was to run my AC units
n2aws
Solar Addict
- Joined
- Oct 24, 2022
- Messages
- 690
Simlarly, I only have a 30a breaker for my input (long story.. I repurposed an existing subpanel to become the critical loads panel, but used the existing wiring which is only rated for 30a.. and I'm waiting until winter time to do the attic work of replacing the wire with thicker.. so I've dropped the breaker to 30a)
But, unlike me or @GXMnow, @ohsolar doesn't have any solar. So, 100% of his consumption beyond the inverter, is going to flow through that breaker. Where I suspect in our cases.. somewhere north of 75-95% of our consumption in being inverted from the DC bus rather than flowing through AC1.
But yeah, if @ohsolar is saying his loads are typically a few hundred watts outside of charging the batteries.. I'm concerned. Like, really concerned. @ohsolar any chance you have a thermal camera? I'd consider going out every so often, and just scanning all the connections looking for hot points. I think at a minimum, I'd set your "AC1 breaker size" to 20 or 30a, just so the inverter limits the current it's drawing through that circuit until you can pinpoint the issue. (Note, I wouldn't even consider this a workaround. this is not a long term solution. I wouldn't even consider it a short term "solution", I'd just consider it "risk mitigation" for the short term, at best.
Last edited:
GXMnow
Solar Wizard
- Joined
- Jul 17, 2020
- Messages
- 2,789
My system does indirectly power my A/C system.
But it only works when the grid is up. My A/C is connected back in the main panel. The start surge comes from the grid. Then the CT's in the main panel see the extra load and ramp up the "Sell to Grid" power to cover the 14 amps that the A/C draws. My central A/C has a 100 amp start surge, so I am not going to try putting that in my backup loads panel. The 14 amp run power is no problem to cover though.
Like @n2aws said, in our cases, most of the power is coming from the batteries, or in my case, my AC coupled PV solar that feeds the backup loads panel. In the evening, once the sun goes down, my XW-Pro could be pushing 15 amps to the sub panel AND 15 amps back to the main panel. It all depends on what loads are active. The XW-Pro is actually very smart. When you set the breaker sizes, it knows to limit the current to not trip the breakers. If I have a large load on in my backup sub panel, and a cloud moves over, the XW quickly drops the charge current to keep the draw from the main panel under 16 amps on the 20 amp breaker. My PLC does try to do that, but the XW does it faster, and then it take 20 seconds or so for the PLC to then set the correct charge current to just follow the extra (now reduced) solar coming in.
With no solar and just charging from grid, you do need the larger input breaker. 60 amps should be more than enough though. Even charging at the maximum 140 amps, the XW only needs about 30 amps at 240 volts from the grid. So you could still be pulling 20 amps at the sub panel. And even if you do pull more current, the XW will reduce the charge current to keep the input current under the 80% rule of the breaker size you entered. So 48 amps with 60 amps in the settings.
You may have an unbalanced load. If the full 20 amps is only on one leg, that could be an issue too. I ran into that when my refrigerator, toaster, and microwave where all on the same leg. Oops. While the XW can handle very unbalanced loads, the breakers will trip on the current in either leg only. I still expect it would see this and still reduce charge current to limit the single leg current, but that could kick in at a much lower total wattage.
Similar threads
