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diy solar

System is DOA! Need advice

leroyinthewoods

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Joined
Mar 16, 2021
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8
Left my breaker box for solar panels unlocked and someone turned off my breakers, inverter has drained my batteries all the way down. No lights at all on the control panel. This is my first system and I need advice on restarting. Do I have to take all the batteries out (16 6 volts, 48 volt system) and recharge them separately, or can I charge part of them enough to restart/reprogram and get the system to recharge itself? Also would like to talk to someone familiar with Schneider Electric Conext 4048 Inverter/Charger with Conext MPPT 60 150 Charge Controller and Conext Control Panel. Not sure I know how to clear the faults and get this back up and running. No help from Schneider Electric! Help!
 
Lithium? Disconnect ALL load and give them time to recover.

I used to leave mine for 24hrs. I was never sure how much time they actually needed.
 
Lithium? Disconnect ALL load and give them time to recover.

I used to leave mine for 24hrs. I was never sure how much time they actually needed.
No, using standard Crown CR235s. The cabin load is switched off and I did try leaving every thing "on" (with no load) all day with good sunlight while I was doing other work on the cabin, got nothing through the charger. No lights at all on the control panel. Thanks.
 
Too particular a procedure to call out. Check the manual - there's a section on SCP controls. Clearing the faults and restarting can all be done through the SCP... but I believe you'll need to have 48v nominal system voltage available to do it (8 of your 6v units) - so you may have to charge batteries up first with a standard 12v battery charger (2 6v in series at a time). Lead Acid won't all have to be perfectly matched to re-commission - just get them close - and it's best to get them back up to speed as soon as possible. The MPPT-60-150 SCC can also charge at 12v (but it would also need to see approximate nominal voltage first). Post again if you have any questions and best of luck.
 

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Too particular a procedure to call out. Check the manual - there's a section on SCP controls. Clearing the faults and restarting can all be done through the SCP... but I believe you'll need to have 48v nominal system voltage available to do it (8 of your 6v units) - so you may have to charge batteries up first with a standard 12v battery charger (2 6v in series at a time). Lead Acid won't all have to be perfectly matched to re-commission - just get them close - and it's best to get them back up to speed as soon as possible. The MPPT-60-150 SCC can also charge at 12v (but it would also need to see approximate nominal voltage first). Post again if you have any questions and best of luck.
Thanks for responding. That is pretty much what I thought, just wanted to make sure before I screwed up something. I'll start recharging. Probably will need some tutoring on restarting once I get it charged up. Being my first attempt at solar, seemed to me the manuals were almost specifically written only for the engineers that wrote them.... Appreciate the help.
 
This does not help now, and hopefully would never happen again, still, you should consider putting in a BMS which would have cut-off the batteries before they got that low and at least given you a chance.
It is cheap insurance (well, compared to the battery bank).
Overcharged cells and overdrained batteries make me worry so I put cheap daly BMS's on every pack hehe
 
This does not help now, and hopefully would never happen again, still, you should consider putting in a BMS which would have cut-off the batteries before they got that low and at least given you a chance.
It is cheap insurance (well, compared to the battery bank).
Overcharged cells and overdrained batteries make me worry so I put cheap daly BMS's on every pack hehe
Yeah, and the sad part is--I thought the Schneider system had that built in...
 
This does not help now, and hopefully would never happen again, still, you should consider putting in a BMS which would have cut-off the batteries before they got that low and at least given you a chance.
It is cheap insurance (well, compared to the battery bank).
Overcharged cells and overdrained batteries make me worry so I put cheap daly BMS's on every pack hehe
He is using LEAD not LFP, no BMS' come into play. Maybe should have read the thread.
 
No, using standard Crown CR235s. The cabin load is switched off and I did try leaving every thing "on" (with no load) all day with good sunlight while I was doing other work on the cabin, got nothing through the charger. No lights at all on the control panel. Thanks.
Typically, any SCC requires the batteries to be at a certain Minimum Voltage so that when the SCC starts up it can identify the Voltage Profile it has to load. Each company has "thresholds" and it varies a little. Therefore if the SCC cannot detect the correct voltage it may not start or may start but with the wrong voltage profile.

The Inverter/Charger is voltage specific obviously so voltage sense to start is not an issue. The trick is to get the Charger to start charging the battery bank up. You do not mention if the Inverter/Charger is connected to Grid AC Input or if you have a Genset connection to it for "backup charging". If either is available to the Inverter/Charger then you should really have no issues in charging the batteries and bringing them back up in voltage.

GOTCHA'S (Lessons learned from an FLA days)
- BEFORE charging, check the electrolyte levels and make sure all the cells are topped up per manufacturer spec with pure distilled deionized water. * They may be a slight bit lower than normal because of the low charge, so leave just a hair extra room when topping them up because as they charge & warm up the electrolyte will expand and potential vent out.
- Once these are charged back to a "Normal" voltage, I very highly recommend running a minimum of 2 hours Equalisation Run to ensure a Deep Charge is in there and NOT just a surface charge which is very likely after a full discharge to "empty".
- At least 2 hours AFTER EQ Charge and the batteries have settled to float or no charge at all, check the electrolyte levels again and then test the Acid with the Hydrometer for the Acid Gravity.
- IF the Gravity is not correct (too low) post EQ, you may have to do another EQ Run. If this is the case, do at 1 Hour run at a time and recheck.

BASIC GRAVITY TABLE
% ChargeSpecific Gravity
1001.255-1.275
751.215-1.235
501.180-1.200
251.155-1.165
01.110-1.130

Hope it helps, Good Luck.
 
Typically, any SCC requires the batteries to be at a certain Minimum Voltage so that when the SCC starts up it can identify the Voltage Profile it has to load. Each company has "thresholds" and it varies a little. Therefore if the SCC cannot detect the correct voltage it may not start or may start but with the wrong voltage profile.

The Inverter/Charger is voltage specific obviously so voltage sense to start is not an issue. The trick is to get the Charger to start charging the battery bank up. You do not mention if the Inverter/Charger is connected to Grid AC Input or if you have a Genset connection to it for "backup charging". If either is available to the Inverter/Charger then you should really have no issues in charging the batteries and bringing them back up in voltage.

GOTCHA'S (Lessons learned from an FLA days)
- BEFORE charging, check the electrolyte levels and make sure all the cells are topped up per manufacturer spec with pure distilled deionized water. * They may be a slight bit lower than normal because of the low charge, so leave just a hair extra room when topping them up because as they charge & warm up the electrolyte will expand and potential vent out.
- Once these are charged back to a "Normal" voltage, I very highly recommend running a minimum of 2 hours Equalisation Run to ensure a Deep Charge is in there and NOT just a surface charge which is very likely after a full discharge to "empty".
- At least 2 hours AFTER EQ Charge and the batteries have settled to float or no charge at all, check the electrolyte levels again and then test the Acid with the Hydrometer for the Acid Gravity.
- IF the Gravity is not correct (too low) post EQ, you may have to do another EQ Run. If this is the case, do at 1 Hour run at a time and recheck.

BASIC GRAVITY TABLE
% ChargeSpecific Gravity
1001.255-1.275
751.215-1.235
501.180-1.200
251.155-1.165
01.110-1.130

Hope it helps, Good Luck.
Thanks for your response. I am in the process of recharging the batteries separately now (removed from the bank). No, I do not have a AC grid connection or Genset connection for this system. Appreciate the information.
 
Yeah, and the sad part is--I thought the Schneider system had that built in...
It does have an LVD built-in. FWIW: If the SW4048 Low Voltage Disconnect (LVD) had been set at an appropriate voltage it likely would have prevented the extreme discharge, and the solar breakers could have simply been reset to charge the batteries. You may want to check that when you restart the system.
 
Thanks for your response. I am in the process of recharging the batteries separately now (removed from the bank). No, I do not have a AC grid connection or Genset connection for this system. Appreciate the information.
It may be prudent to wire up a genset plug for the Inverter/Charger and you do not need a GCSM or such if you are setting up as a manual backup. It's simple enough, and the specs I just glanced at says they can take either 120V or 240V AC input for charging.

The simple manual way is to wire from Inverter to Breaker, Breaker to Input Plug like an L5:30 for the 120V/30A plug on a genset. Then you only have to plug in the genset, fire it up flip the breaker to ON and the Inverter/Charger can then charge the batteries while providing some pass-through power. Breaker between genset & Inverter is because you should never rely on a genset breaker & you want to ensure the Inverter is protected against something going awry.
 
It does have an LVD built-in. FWIW: If the SW4048 Low Voltage Disconnect (LVD) had been set at an appropriate voltage it likely would have prevented the extreme discharge, and the solar breakers could have simply been reset to charge the batteries. You may want to check that when you restart the system.
I will look at that when I restart. What would you feel is a proper low voltage threshold? So far, all the discharged batteries have been reading around 5.6-5.7 volts. I had expected it to be somewhat lower.
 
It may be prudent to wire up a genset plug for the Inverter/Charger and you do not need a GCSM or such if you are setting up as a manual backup. It's simple enough, and the specs I just glanced at says they can take either 120V or 240V AC input for charging.

The simple manual way is to wire from Inverter to Breaker, Breaker to Input Plug like an L5:30 for the 120V/30A plug on a genset. Then you only have to plug in the genset, fire it up flip the breaker to ON and the Inverter/Charger can then charge the batteries while providing some pass-through power. Breaker between genset & Inverter is because you should never rely on a genset breaker & you want to ensure the Inverter is protected against something going awry.
Well wait, I may have answered that wrong. I do have a genset plug wired to the AC/DC panel, just wasn't aware that I could backfeed through to the charger. Is that possible? Gotta remember, I'm totally novice at this. You guys are miles and years ahead of me.
 
The inverter should have an AC IN port for Genset/Grid power which should be capable of sensing when power is there and switching to it. Again, I am NOT familiar with the Schneider product line, I use a Samlex EVO Inverter/Charger & Midnite Solar Controller.
 
Why shouldn’t you rely on a genset breaker?
They are usually really cheap crappy breakers and not worth relying on.
An external breaker between Genset & target devices is not unusual and fairly common even when there is a dedicated genset with GCSM control from an Inverter/Charger system.
 
They are usually really cheap crappy breakers and not worth relying on.
An external breaker between Genset & target devices is not unusual and fairly common even when there is a dedicated genset with GCSM control from an Inverter/Charger system.
Even UL listed ones?
 
I will look at that when I restart. What would you feel is a proper low voltage threshold? So far, all the discharged batteries have been reading around 5.6-5.7 volts. I had expected it to be somewhat lower.
As a general rule, I would set my LVD at 47.6 (with a 15 second delay to allow for surge). That is for a properly charged FLA battery with a reasonable AH capacity based on normal loads. You'll want to adjust that based on your manufacturer's specs, your preferred Depth of Discharge and the condition of your battery bank. Once you get back up, you'll also want to do an equalization charge, with a careful distilled water check/fill. Best.
 
OK guys, success today. I recharged 12 or the 16 batteries, reinstalled and serviced them. All I had to do was clear the fault, system had not lost original programming. The system immediately did a forced charge and then an equalization charge without any program changes. Was a bright sunny day and perfect conditions to get it cranked back up. It was back up to near 57 volts in about 4 hours of sun. Also, going through the menu I found the Schneider 4048 was factory set for LVD at 43 volts. I may raise that up a bit per GVSolars recommendations as soon as I get a bit more comfortable with the control panel. Now, another question; my cabin is approx 30 miles from my home, remote and totally off grid. I have no phone connection to check the system but I'm usually nearby at least once a week or more. Given that situation, would you recommend leaving the system "on" full time or would you shut it down when it's not in use? Thanks to all of you for the advice!
 
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