Brewman
Solar Enthusiast
- Joined
- May 16, 2020
- Messages
- 511
Looks to me it will pull from the one giving the most power.
need a little help
- Thread starter randerson
- Start date
Looks to me it will pull from the one giving the most power.
Ampster
Renewable Energy Hobbyist
Then you don't need to use both inputs. I double checked the math on the Amps from the panels. It is 8.85 per panel. Since you are putting them in series pairs only the voltage doubles. Therefore you will have 4 sets of 8.85 Amp for a total of 34 Amps. You will need some Y connectors to combine those. Some people use a combiner box with separate breakers or fuses on each series pair. It does make diagnosis easier in the future if their are problems.
If you are looking at 80ft one-way / 160ft round trip distance and a 2S4P array (Voc 75.2V, Isc 35.4) and 8AWG wire, Vdrop will be 5-6%, which is less than ideal (the common target is <2-3%) but not an absolute dealbreaker. If you could source one more panel you could go with 3S3P which would drop you into the 2-3% Vdrop range.
I sent an email last night to see if i can add a panel to do 3s3p. It takes a day or so to get emails back from the seller so i hope he has not shipped yet. freight shipping to my town was $150. The shipping cost is the same for one panel or ten. i do not want to pay shipping twice for a new order.
got an email back from the pip manufacturer. Yep it does draw from only one panel input at a time. If you put 1000 watts in PV1 and 1000 watts into PV2 the max you can draw is 1000 watts. one array gets shut off depending in who has better sun. Seems like an expensive option to get max watts all day. I guess it would benefit a roof mount owner if they have trees that block the sun for hours out of the day. Here is the email they sent.
I got a letter back from the ebay seller. i sent him an invoice to add another panel as he has not shipped yet. total panels will be 9 now once he excepts my offer. you guys are great. i thank you for all of your help. i hope others can view this post and learn too..... you guys are awesome!!!!
Ampster
Renewable Energy Hobbyist
Yes that is 3S3P.
That would be great if you can get one more panel added to your order.
That would be great if you can get one more panel added to your order.
Ampster
Renewable Energy Hobbyist
I also reread the beginning and you mentioned that you think the panels may not have connectors on them and that may make it easier to put them into a combiner box or two than buying expensive MC-4 connectors. When you get them or confirm what connectors they have you can decide.
I bought some used panels that had the old MC-3 connectors and I replaced them all with MC-4 connectors. I actually only needed to replace the four panels that were connecting to microinverters because the other seven were in a 7S string but I had the kit and it made my system more flexible if I wanted to add optimizers later for some shading.
Lots of cost benefit options.
I bought some used panels that had the old MC-3 connectors and I replaced them all with MC-4 connectors. I actually only needed to replace the four panels that were connecting to microinverters because the other seven were in a 7S string but I had the kit and it made my system more flexible if I wanted to add optimizers later for some shading.
Lots of cost benefit options.
I did.. seller contacted me and I added a panel... 9 on the way now
I picked up a 3 into 1 splicer pack already ...(rated at 50 amps) and a 10 pack of MC-4 connectors just in case. I also picked up a mount for my 9th panel. With this covid19 stuff some things will take forever to get here and i wanted to make sure i was not waiting on a connector.
my trailer is only 70 ft long so i will probably be able to cut of 20 to 30 ft off the 80ft run to the inverter too. I just wanted to make sure I had enough to run it under the house for a good looking install.
Attachments
you have got to be kidding me. my mpp will not turn on .
it is all hooked up and hooked up and right. i used the hammer crimper to put on new ends sized right for the unit. i throw the power switch and nothing. i even tried reversing cables..... nothing.
.it is all hooked up and hooked up and right. i used the hammer crimper to put on new ends sized right for the unit. i throw the power switch and nothing. i even tried reversing cables..... nothing.
Similar threads
