A very big THANK YOU for taking the time to post the vid. I am fitting my entirely off grid cabin and house with solar and literally in the wiring phase right now. Your video was a godsend as no matter how much you read the instructions a video is worth a thousand words of instructions. I hope you feel awesome knowing your video helped a few thousand people understand solar wiring better!
I am just getting into this and bought the MNPV3 and had been starring at it wondering how the positive combiner worked..LOL.. This explained it very well. Thank you
also are the red and green wires leading out all8 awg like the white wire? I assume so. sorry for being such a pest. You could solve a major headache that I have right now about buying more than one disconnect boxes for my different strings. Thanks
The nongrounded current-carrying conductor may be any color other than white, gray, green or green with yellow stripes. So if the negative is grounded your white wire is correct. If the PV system is ungrounded, it’s wrong.
I see you fit 4 of your PV wires into each knockout. Are those 3/4" fittings coming in the panel entry? What gauge PV? I'm looking to do the same thing - My PV wire is 10 AWG.
@@mark_osborne Thanks for the quick reply, Mark! Actually in that case I did have one more comment/question for you. At the end of the video you mentioned measuring DC amps by connecting to the positive leads at the bottom of your breakers. I was thinking if you turn all your breakers off, you could safely connect your multimeter directly to the (-) and (+) main bars. Then just turn breakers on briefly, take your amp measurement, and turn off, and just do that one at a time for each breaker. You lose all your solar input temporarily while doing the test but seems like it should be safer (no arc'ing) and don't have to put hands directly on hot wires. Thoughts?
newbie question. If I have 3 strings and I have this disconnect/combiner box but don't need to combine 3 into 1 or have a 2 in1 series/parallel and i series into the inverter but have 2 or 3 separate positive and negative running into it. can I do that?
That sounds like my set up. I have two groups of 39 volt 9 amp 315 watt panels wired series coming into combiner with plans to add one more group shortly, can you do a video of wiring combiner box to your charge controller I have the same midnite solar 200 amp Having a hard time getting AN Electrician to wire my system in far north east Texas
Well that's simple, all you do is run the (red) positive to the + (PV) positive terminal in the charge controller, and the white - (PV) to the negative, and the ground to the green
So I have two red positive and two negative wires from solar panels. I just need to come out of combiner to the controller? I have battery bank, 48 volt wired with a positive and negative. So Thant should start charging my batteries? Thanks I will ask questions later on how to wire the inverter.
@@rmosborn I think so, however, I'm not sure if the electrical code requires 2 different ground paths ? You probably want to do a little more research on the subject if you are worried about being code compliant
@@mark_osborne I have another question. Combiner box and charge controller is wired. Do you know anything about Outback GS4048 inverter wiring it would be 48 volt dc input and 230 out put. Would love to grid tie and use as backup if grid goes down. Could I grid tie with a disconnect to grid. Thanks
having watched the video and noticed 2 positive wire and 2 negative wires (white) and one green running into the 1/2 inch outlet pipe. just to confirm, is this two sets of wires running into the inverter? Also I noticed that at the top you use the 2 ends for the positive wires where there is 2 sets and then a space then three sets. Is this done on the combiner bust? Also what about lightning protection etc. can you install that also?
The 2 positives and 2 negatives was because it cost less to run (2) #8 wires than a single #6 and I ended up with a lower voltage drop. So those (2) red wires go to a common lug at both ends, same for the white. That is a continuous bus bar above the breakers, so it's as tho the red wires are on a common lug. I only needed 5 breakers and simply installed them with a gap between them, I could have just as easily had them all touching each other. Yes I have since added lightning protection.
@@mark_osborne How did you add the lightning protection? Did you have to rearrange the positive connections at the top or did you just wire the positive of the lightning protection to any space? Thanks again
Hi Mark I'm a little confused about your white wires. What do you mean by power room. I understand the 2 wires to avoid voltage drop, but where do they go to? Thank You!
Both red wires go to the solar shed. I doubled them up to lower the voltage drop. Same with the white (-) wires. The red wires are harvesting energy from the bus bar. The bus bar is being supplied energy from the breakers. The breakers get their energy from the positive lead (going into the bottom of the breakers) - coming from the solar panels.
Yes, I doubled up the positive and negative wires so there would be less voltage drop. I could have used thicker wire, but it's a bitch to work with. If I recall, it's 190 foot run to the charge controllers, my voltage drop was around 2% using (2) #8 wires.
Hi Mark thank you for this video. My question to you is why do you have black and white wires together on the left bus bar. Also what is the flat bus bar behind your breakers for?
The white wires are (-) negative running to the charge controller - white per the National Electric Code (NEC). The black wires attached to that same bus bar are the (-) negative side of coming from the solar panels. The flat bus bar behind the breakers combines the 5 (+) positive black leads coming from the solar panels. The bus bar has a finger that extends down into the top of each breaker and is secured with a screw/clamp. At each end of the bus bar you can see the two - #8 red (+) positive wires that feed power to the charge controller. Hope this makes sense.
PV cable comes in black and red. Most installs we use black jacket for both +/- so we don't have to carry an additional spool in the trucks. We usually leave the - as is and mark the positives going into the combiner breakers, or fuses, with red tape. We don't make a pull and connect the cable to the breakers. Instead we pull all cable runs into the combiner box and mark the positives with red tape prior to making the pulls. Then when we trim the box, we'll take the positive and mark them again with tape near the breakers and then bond to the breaker. We also add a label inside the box lid showing the panels used in each string and the breaker number. This saves time for those who come after knowing which panels are in the string without having to trace or consult the plans. Really good video. Thanks for sharing.
Hi Mark, I bought a lot of crap from Alt-E, but of course after they sent me the stuff they wanted to sell, I have no more communication with them. Yes! they promised to guide me, but without communication, I'm Assed-out. Excuse me! Just wanted to ask you, if you've done anymore videos, obviously I can understand you "Clearly!" I wanted to ask about the red wires connected to the positive, (Left Top) and (Right Top) where are they coming from. (Green Left) buss bar where is that from? I'm double checking my system. Thank You for your fast response! Love your video because you are not trying to just hear yourself talk. Have you seen a lot of the videos that ramble on and on?
The two #8 red wires positive wires (red per NEC) run some 175 feet to the power room where they are connected to the input of the Midnight Classic 200 charge controller. The green #8 wire (green per NEC) also runs some 175 feet to the ground lug on the Midnight Classic.
nice been slowly buying what i need on a shoe string budget 400 w mono got the 40 amp MPPT trace controller and the little box that go's with it to found it was just not going to do it as far as expansion so i saved up and bought a midnight solar 150 i bought wielding cable for the batteries now i need to buy the ends found i am going to need a combiner box oh and i got a lighting arrester 88 bucks the alt e store its were i got the 150 classic as well good price now it fuse and breaker the one thing i regret it the inverter i should have gone 24 volt don't know why but i couldn't get 12 volt out of my head lol so now i am committed to 12 volt set up
Sell the inverter. You are really limiting yourself by building a 12 volt system IMO. Solar panels are so cheap now you'll be buying more in short order ;-)
Yes the power room contains the charge controllers, battery and inverter that converts DC to AC current. The charge controllers have some surge protection built -in, although there are more robust surge protectors available.... it's just a matter of how much money you want to spend ;-)
Please call MidNite solar on that please. I believe the ground inside the MidNite is for wind turbines only. Or you could disable you ground fault inside your classic. At least mine are with no ground inside the classic. It doesn't hurt to ask them. Please let me know what they tell you. Thanks
scroll to page 26 of the Midnight Manual - it clearly shows the ground running to the controller when used with solar panels, as well as a wind turbine ;-) www.midnitesolar.com/pdfs/Classic_manual_REV_2056.pdf
While a single run of #6 THHN would have worked fine in terms of ampacity, I went with 2 runs of # 8 as the voltage drop was lower over the 175 foot run.
The ISC (short circuit amp) of the 3 panels in series (on each breaker) is only 9.5 amp, so a 15 amp breaker is appropriate. While it's true I could use a lighter cable, #12 provides for a lower voltage drop between the panels and the combiner box.