diy solar

diy solar

Combiner Box - <10A

Why in direct sunlight was the amperage so high?
Because it was getting maximum insolation potential in the direct sun. Plus, when it is cooler output voltage goes up.

My two old windyNation 100W panels and P30L pwm hit almost 12A a few times.
 
Not a problem. THe only issue you could run into is “overcharging the batteries.” This is hard or impossible with lithium, and more of an issue for a FLA battery where they could be limited to max charge of 1/10th the C20 rate. For my 4 large golf cart batteries, this came out to 60 amps.

The load slot will not handle an inverter, but is designed for low amperage devices. IMO, they provide so little power, they should not be on SCCs. The only time a load could be useful is some can run a low amperage light at a programmed time, or will shut off a load once the battery drops to a certain voltage.

Victron is pretty good at giving the max wire gauge that will fit in heir SCCs. I have a 15 amp SCC that is rated for 12 AWG, and the only way I can get 10 AWG in there is to trim the 7 strand wire strands off one at a time until it fits. Probably not a good practice. Perhaps finely stranded welding wire would fit.
had an issue when trying to feed both the inverter and battery bank from the controller simultaneously. I tried a 'T' type electrical splitter - basically 3 port heavy duty component I bought as an electrical supply shop. Fed the solar controller output into the center port on the T, left port fed battery bank and right port fed the inverter. Connected the battery bank first and all was good. But when tried to plug in the line to the inverter from the remaining port I got all kinds of sparking so I aborted that. Is the problem the T, and I need to simply run 2 lines out of controller itself (2 + lines from the Battery+ slot on the controller and 2 - lines from the Battery- slot on the controller???)
 
had an issue when trying to feed both the inverter and battery bank from the controller simultaneously. I tried a 'T' type electrical splitter - basically 3 port heavy duty component I bought as an electrical supply shop. Fed the solar controller output into the center port on the T, left port fed battery bank and right port fed the inverter. Connected the battery bank first and all was good. But when tried to plug in the line to the inverter from the remaining port I got all kinds of sparking so I aborted that. Is the problem the T, and I need to simply run 2 lines out of controller itself (2 + lines from the Battery+ slot on the controller and 2 - lines from the Battery- slot on the controller???)
Using a properly rated disconnect helps with the sparking.
 
Was it 12.5 amps coming from the panels, or from the charge controller?
The reading is on the display of the charge controller. I assumed that reading is what is from the panels. The solar controllers can increase amperage above what comes from the panels??
 
Using a properly rated disconnect helps with the sparking.
The sparking occurred when I was connecting the controller to the battery bank and the inverter - there were no panels connected yet. All my MC4 connectors are before the controller - between panels and controller. I have no quick connects after controller - should I? BTW - I have shunts involved to connect my charge and discharge meters. No issues when I just did the batter bank, but the significant sparking was when I attempted to then connect the inverter.
 
In series, the voltage adds together. And, the amperage stays the same.
In parallel, the amperage adds together. And, the voltage stays the same.
 
There should be a fuse as close to your battery bank as practicable.
After the fuse there should be a disconnect, that you now know needs to be capable of disconnecting "under a load". Many disconnects are not rated for use under load. Shop carefully, read the product information carefully. If it does not say it is safe to use under load, it probably is not.
 
The sparking occurred when I was connecting the controller to the battery bank and the inverter
the sparking was the inverter capacitors loading up. Look up ‘pre charge resistor’ here on this site
 
Thx VoltInstalls! I watched a couple videos on the subject and seems straight forward. Only thing that still concerns me is the videos indicate for <1700 watt inverters the need to precharge the inverter capacitors to eliminate spark should not be needed. My inverter is 1000 watt so still concerned I got such a spark when attempting to connect my inverter via a T. But I will try the pre charge resistor to see if it makes a difference. Thanks again
 
With my system, I think there is more than just the inverter that needs precharge.

I have a 70 amp Dc to Dc converter and a 24 volt 35 amp charger. Both those spark when first hooked to DC. With all three routed through the master off switch, There’s quite the spark when the switch is turned on after being off for a while. That is why I’m installing a resistor and a new switch.
 
the videos indicate for <1700 watt inverters the need to precharge the inverter capacitors to eliminate spark should not be needed
That’s a subjective opinion imho

If you’re an experienced welder maybe the sparks don’t bother you - but they can still unflatten the contact areas of the parts that should have good contact area without metal pilling on their surfaces.
 
I'm a big fan of "NO SPARKS". The first time the Boss Lady sees sparks, I'll get the evil eye and a one way ticket to the dog house.

There were some folks showing off their pre-charging setups a while back, I searched for the thread I am referring to but could not find it.
Here is a thread where the subject is discussed and Will produced a video on the subject. Post 15

 
Here's a couple setups in this thread:

 
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