Random shutoff of Charge controllers
ChuckKautz
Registered Users Posts: 10 ✭✭
I have a grid tied system that allows net metering. I have an 8100 W
array with 2 Schneider Electric XW6048 inverters, 4 charge
controllers,and battery for backup. The battery is flooded 875 Ah and
48V. The charge controllers seem to shut down randomly. Sometimes all of them are working, sometimes none, and everything in between. Is this a problem with the communications board or could it be something else?
Comments
http://members.sti.net/offgridsolar/
E-mail [email protected]
Dave is the one to help you here--Just my basic debug questions.
-Bill
And it is OK if the charging sources are not in sync if each is programmed correctly. I.e., you may have one charging source in float, while another is still in absorb. As long as the battery bank is "happy" (i.e., correct charging voltage at terminals, and absorb time is roughly 2-6 hours--shorter if shallow discharge, longer if 50% of more discharged), then that is a good start.
Get a good quality voltmeter and measure the DC terminal voltages of each device (when current is flowing--Charging, discharging, and resting). You should not have much more than a few tenths of volts difference between the battery bus voltage and the terminal voltages of each of the major DC devices (XWs, charge controllers, etc.). We are looking for "differences" here... You have a bunch of "matched" components and they should be all running about the same voltage/conditions. Any "differences" need to be further researched.
And look for any corrosion (can be from battery electrolyte, or even just rain water following a cable to a terminal block), loose DC wiring connections, and signs of overheating at the terminals (browning).
Also, I suggest getting an AC+DC Current Clamp Digital Multimeter... The current clamp is very easy and safe to use when measuring current flow--Just zero (DC clamp meters need zeroing) and clamp on a single wire to measure current flow. Great for debugging and understanding what your system is doing.
https://www.amazon.com/UNI-T-Digital-Handheld-Resistance-Capacitance/dp/B0188WD1NE (cheap, good enough)
https://www.amazon.com/gp/product/B019CY4FB4 (nice mid-range cost meter)
I am not the person to talk about detailed debugging of the XW system and communications issues. I have seen here that a good place to start is to turn off the AC/DC power to each of the units (inverter, charge controller, etc.) for at least 5 minutes, and then restart in the proper order (DC bus on first, then connect solar array next, etc.).
Another thing that has sometimes helped... Resetting to factory defaults, then programming again (make sure you have all the setting written down). On occasion, the memory can be corrupted...
Other than that, check the comm bus wiring (inspect the connectors, make sure wires have not been pulled while replacing the battery bank, no corrosion, that wires and bus terminators are in place, etc.).
That is about my limit on the XW/solar chargers...
Perhaps Dave or others can help with the details.
-Bill
And what is stopping charging... The MPPT solar charge controllers, the XWs, a combination of both?
With networked gear--You have the behaviour of both the individual components, and the behaviour of everything networked together. You might find that one MPPT controller is acting "squirrely", and when connected to the network, the others start misbehaving too.
-Bill
PS: Any other events (like lightning in the area 7 months ago) that may have happened?
You want the Vbatt voltage at the controller and the battery bus to be less than 1/2 volt difference between the two.
The solar panel voltage, you would want it to be at least 1.3x the Vbatt voltage--Especially if you are reading 0 Watts (1.3x 59 volts = 76.7 Volts)... If you know the Vmp of the panels, then you should see at least Vmp-array*0.80 (hot panels, under MPPT loading).
If you have no current/power flowing, something closer to Voc-array (X number of panels in series * Voc -- Voltage open circuit).
-Bill
And when shutting down solar charge controllers, turn off solar array power first (or do the work at night), then turn off DC battery power.
Not picking on your controllers--Just good practice for most. The controllers usually use DC Battery voltage to power their internal computer. Powering from solar first may give you a "bad computer boot" and/or read the wrong battery bus voltage (most controller auto-configure to the bus voltage 12/24/48 volts when they boot. Connecting solar power first can really confuse them).
-Bill
http://members.sti.net/offgridsolar/
E-mail [email protected]
Second system 1890W 3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah FLA 24V nominal used for water pumping and day time air conditioning.
5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
-Bill
Agreed if that if that's all that was done, however there have been 3 cooks in the kitchen, a verification wouldn't hurt.
Second system 1890W 3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah FLA 24V nominal used for water pumping and day time air conditioning.
5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
Charge controllers usually make their "decisions" based on voltage and sometimes time (2-6 hours absorb timer, then fall back to float voltage). Starting with a voltmeter and seeing what voltages are present tells us if the basic wiring is correct.
-Bill
The reason I asked about faults and warnings is this is all logged. There are historical logs as well as current logs. These are logged in the network system and each device logs it's own faults and warnings. They have dates also.
Chuck is not answering the question even though he thinks he is. Are there Faults and Warnings ? What are they?
In the end this most likely is a configuration problem if there are no faults or warnings.
http://members.sti.net/offgridsolar/
E-mail [email protected]
Second system 1890W 3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah FLA 24V nominal used for water pumping and day time air conditioning.
5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
-Bill
There is the second thing I asked, and that was warnings.
You might want to read how XW system treats warnings, how they can escalate, and how they become faults.
Read the warning and fault numbers and you should post a 24 hour screenshot of the battery summary screen. A picture is worth alot and it removes reading errors.
A config error can happen from the grid. A surge can change a default or programmed setting. In offgrid we surge protect everything to avoid the loss of power.
http://members.sti.net/offgridsolar/
E-mail [email protected]
The configuration fault could be related to various things such as the sync cables, more than one controller being set as master, errors occurring during a firmware update, interference being induced into the Xanbus communication cables to name a few.
Since there have been multiple people working on the system which worked prior to the batteries being changed I would be inclined to reset to factory defaults then reconfigure the whole system.
Second system 1890W 3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah FLA 24V nominal used for water pumping and day time air conditioning.
5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.