Is there a way to add more solar panels to a system but have the system limit the extra volts/amps if its not needed? I can get my hands on some good used panels and wanted to install some that get sun other times in the day. This would help to get more solar even during overcast days.
Adding more solar panels
- Thread starter Simonbr2
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Rednecktek
Solar Wizard
The easiest way is to set up another SCC with the new pane3ls and parallel them in to the existing battery bank. The SCC will only put out what the battery can draw so having multiple arrays isn't going to hurt them.
It's also common to see arrays facing different directions to gather light earlier in the day or later in the afternoon if that's a better position for them.
It's also common to see arrays facing different directions to gather light earlier in the day or later in the afternoon if that's a better position for them.
The power from a solar panel or from the charger/inverter that is connected to a solar panel system.....that power is based on the load end. You can have 5000 watts of panels and if you have a 300 watt load, you will pull 300 (plus losses) from the panels.
What you can't do is put more panels in series and push the voltage over the max PV input of your charger/inverter. That is bad.
"Over paneling" is a common practice. I have a system (for example) where I put 3 series, 2 parallel into a charger. 4 panels in series would be too much voltage. I could bring up another 3 in series to have 3 parallel strings. But on a good day that might be more amps than I want on my 10 gauge wire. But my charger will current limit and not use more than it can digest. What did in this case was put more panels on a second charger because I had the charger, but I could have run a larger wire.
What you can't do is put more panels in series and push the voltage over the max PV input of your charger/inverter. That is bad.
"Over paneling" is a common practice. I have a system (for example) where I put 3 series, 2 parallel into a charger. 4 panels in series would be too much voltage. I could bring up another 3 in series to have 3 parallel strings. But on a good day that might be more amps than I want on my 10 gauge wire. But my charger will current limit and not use more than it can digest. What did in this case was put more panels on a second charger because I had the charger, but I could have run a larger wire.
yes the SCC will have a limit for sure which needs to be respected, so I guess the only way would be to add a second SCC for the new strings (serried/paralleled). If the SCC are not connected they should still respect the settings for the charging and not cause any problems I am guessing. Would it be ok if they were not the same size, like having a epever 40a and a second but only at 30a?
Hedges
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You may be able to add more identical panels in series, if it doesn't exceed max voltage specs.
You can probably add more panels in parallel. All series strings of panels should have similar Vmp. Up to at least input current rating or PV wattage rating of SCC.
Most (but not all) SCC tolerate PV array of excess current or wattage rating, just doesn't draw more than it needs.
Some strings oriented different from others could allow 50% extra panels without increase in max current/power, instead extends hours of production.
Yes, multiple SCC of different wattage is OK.
Make sure total output current of all SCC doesn't exceed max charge current the battery can accept.
You can probably add more panels in parallel. All series strings of panels should have similar Vmp. Up to at least input current rating or PV wattage rating of SCC.
Most (but not all) SCC tolerate PV array of excess current or wattage rating, just doesn't draw more than it needs.
Some strings oriented different from others could allow 50% extra panels without increase in max current/power, instead extends hours of production.
Yes, multiple SCC of different wattage is OK.
Make sure total output current of all SCC doesn't exceed max charge current the battery can accept.
On multi SCC, I have two Growatts, each with its own array and both charge the same battery. In additions I have an EPever 40amp on another array charging the same battery. I have a DC breaker on each of the PV arrays, right at the charger location. It is okay to have them on at the same time. They just do their work to charge the battery. I have some portable battery boxes as well. I can kill the PV input to the EPEver and connect it to my portable battery and then solar charge my portable unit. So the EPEver has added extra options for my solar efforts.
For my main system I have the Midnite Classic 150 with the Wizbang shunt which allows me to limit end current to the battery to 84 amps. Is there anything similar device that can be added to the main cable going to the batteries for this type of setup. I wouldn't want to send too much current to a battery bank.
Are there other SCC that have this feature? I have a couple friends I am helping out and they only have the epever currently
Hedges
I See Electromagnetic Fields!
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Midnight Classic talks to Wizz Bang Jr.
Victron charge controller is instructed by Cerbo, which monitors its shunt.
Any all-in-one should be able to regulate battery current because it knows what inverter uses.
AC coupled systems have a large AC to battery charger, so additional GT PV inverters are regulated through that.
Simplest for you should be to put all SCC and inverters through the Wizz Bang Jr., reducing output of Classic as needed. You could add other SCC which would not get reduced, so long as their max current isn't too much. But I'd think you'd want more Classics.
I think the feature matters more for lead-acid, where there is a target current desired.
For lithium, usually anything up to 0.5C is fine. Except when temperature approaches freezing.
Victron charge controller is instructed by Cerbo, which monitors its shunt.
Any all-in-one should be able to regulate battery current because it knows what inverter uses.
AC coupled systems have a large AC to battery charger, so additional GT PV inverters are regulated through that.
Simplest for you should be to put all SCC and inverters through the Wizz Bang Jr., reducing output of Classic as needed. You could add other SCC which would not get reduced, so long as their max current isn't too much. But I'd think you'd want more Classics.
I think the feature matters more for lead-acid, where there is a target current desired.
For lithium, usually anything up to 0.5C is fine. Except when temperature approaches freezing.
This might work for my situation but for others that have smaller systems only have the Epever 40a SCC, would be nice if there was a stand alone shunt device that would have current limiting features.
"stand alone shunt device that would have current limiting features." A shunt (in this context) is a calibrated low resistance path, across which you can measure a voltage. There is no way a shunt can dynamically control current, because it is just a resistor. A programmable DC to DC converter type device would work. In the normal case one would not put in a charge controller that could swamp the battery with too much current. If you want to do that, make sure you install a programmable current type charger.
I do have an Epever 40A that I do some supplemental charging of my big battery and also for a smaller battery. When I want to charge my small battery, I disconnect one of two parallel paths of my 2s2p array to cut the power in half. That is my small system current limit.
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