WYtreasure
It's not happy hour, I'm just like this.
Hello folks, I am new to solar and this is my first build. I have studied quite a bit and now feel confident that I know enough to be dangerous. Any corrections, advice, “Do Not Do This”, or other input would be greatly appreciated.
Want more info, please ask and be patient, I have a dumb phone that is smarter than me.
Links to information will be studied and appreciated.
I’ve visited many sites but have not found “Solar for extra special dummies” yet.
Following is as in-depth as I could get on the first phase of my system. The second phase will just double the panels and batteries. I have tried to avoid confusion by not discussing the second phase in this post, but I am considering the expansion in all my calculations.
After reading a few responses I am editing this, and the following page so no one wastes their time.
The ARRAY of Solar panels will probably be in the 300 watt range.
Wire runs will probably be the same distances, but volts, amps and other data will change when I decide on panels.
Combiner box, Controller, Batteries will remain the same.
End Edit #1.
Edit #2, 12-12 5:30pm
Trying to get this thing cleaned up.
THE ARRAY: I am now in search of panels in the 350 watt range.
The array will be entirely composed of Newpowa NPA100S-12H.
The system is 12 12v, Voc 20.23v Isc 5.89a, 100w, panels.
There will be 6 panels in series with 2 strings of less than 26 feet to the nearby combiner box.
I believe 121.38 (Voc) volts and 5.89 (Isc) amps of current will run to the combiner from each string.
I found a good source to find out if any inline fuse(s) and/or diode(s) will be needed as I connect my panels in series or proceed to the combiner.
diysolarforum.com/resources/fusing-wire-sizing-guidelines-for-solar-panels
Additional wire and connectors will be needed to reach the combiner. The farthest panel should be less than 25 feet from the combiner. I intend to use 8 or 10 awg solar cable, for a max 2% loss up to 26’. The wire will be of appropriate color and IP68 connections will be used whenever possible.
Shading of individual panels will never be an issue, unless I am standing there scratching my head.
THE COMBINER BOX:
MidNite Solar MNPV6 Combiner will be the last exterior component of the system.
At the combiner I will combine strings to up the voltage for the 55' run to the controller.
On the combiner box I believe the MidNite Solar MNSPD-300-DC 300V Dc Surge Protector Device would be a good idea.
Breakers being considered are manufactured for MidNite and limited to 150 volts.
Am I correct in assuming my breakers will be tripped by any voltage in excess of 150?
What about those sub-zero mornings? Will I be running outside to reset breakers sometime after sunrise?
If the breakers trip at 150+ volts, my charge controller should never experience “HyperVOC” or ever be subjected to any “OVERVOLTAGE” condition. Seems as though I am adding an additional level of protection for everything downstream. I’m good with that provided I am correct.
COMBINER OUT to CONTROLLER IN: 55'
Wires leaving the combiner will be in schedule 40 PVC conduit with 3 large radius 90 degree elbows throughout the entire run. The box will be mounted on and the conduit will pass through a 12” thick concrete wall and into a garage, across the ceiling of a bedroom (oh joy I get to do crown molding), into a very shallow attic and finally down into a closet to join the remaining components of the system.
The intent is to place the controller, batteries, inverter (not above batteries), gauges Etc. within a closet, with louvered doors, inside the living quarters of my residence. Can anyone think of a reason I should not do this?
My research leads me to believe up to 4 strands of 6 awg will live happily ever after inside ¾” conduit.
Using the initial panels, which I will not be using, and numbers from the MidNite Sizing Tool, which you can see below:
I am guessing between 102v and 150v depending on temperature and sunlight and up to 11.78 amps of current will be carried to my controller when the amps are at 100%.
On those hot days with minimum sun I need to get 102 volts 55 feet to the controller with minimal loss (2%). Again, research leads me to believe 6 awg will get almost all the volts there. I did look at a few wire/cable sizing sites and they produced conflicting numbers, so I am leaning towards 6 awg THHN THWN Stranded Copper Building Wire; Yes/No/Maybe?
I am living on the High Plains, I get snow, massive thunderstorms with a great deal of lightning, excellent sunshine, and a lot of 60+ mph winds. Larger panels are not really an option and these will be mounted pretty close to the ground with a lightning rod nearby.
Input would be appreciated before I push the buy button. Great input so far, THANKS
How I got my numbers:
I used the Classic String Sizing Tool at midnitesolar.com/sizingTool/index.php
I could NOT figure out which numbers to plug into VOC or VMP Temp Coefficient boxes, so I left them set at default.
The solar panel manufacturer has these numbers on their website: It’s over my head folks.
Temperature Coefficient Of Voc -(80+/-10)mV/ (I am assuming the little “0” means “Degrees”)C
Temperature Coefficient Of Isc (0.065+/-0.015)%/ (assuming the little “0” means “Degrees”)C
Temperature Coefficient Of Power -(0.5+/-0.05)%/ (assuming the little “0” means “Degrees”)C
support.newpowa.com/support/solutions/articles/63000148010-npa100s-12h
Here are the other numbers from the manufacturers website. Amazon numbers differ from newpowa.com.
NPA100S-12H
Monocrystalline Module
ELECTRICAL CHARACTERISTICS
Type NPA100S-12H
Power Output(W) 100W
Voltage MPP Vmp(V) 17.0
Current MPP Imp(A) 5.89A
Voltage Open Circuit Voc(V) 20.23
Short Circuit Current Isc(A) 6.25A
Temperature Coefficient Of Voc -(80+/-10)mV/ C
Temperature Coefficient Of Isc (0.065+/-0.015)%/ C
Temperature Coefficient Of Power -(0.5+/-0.05)%/ C
NOCT (Air 20 degrees C; Sun 0.8kW/meters squared wind 1m/s) 47+/-2 degrees C
FINI
Want more info, please ask and be patient, I have a dumb phone that is smarter than me.
Links to information will be studied and appreciated.
I’ve visited many sites but have not found “Solar for extra special dummies” yet.
Following is as in-depth as I could get on the first phase of my system. The second phase will just double the panels and batteries. I have tried to avoid confusion by not discussing the second phase in this post, but I am considering the expansion in all my calculations.
After reading a few responses I am editing this, and the following page so no one wastes their time.
The ARRAY of Solar panels will probably be in the 300 watt range.
Wire runs will probably be the same distances, but volts, amps and other data will change when I decide on panels.
Combiner box, Controller, Batteries will remain the same.
End Edit #1.
Edit #2, 12-12 5:30pm
Trying to get this thing cleaned up.
THE ARRAY: I am now in search of panels in the 350 watt range.
The system is 12 12v, Voc 20.23v Isc 5.89a, 100w, panels.
There will be 6 panels in series with 2 strings of less than 26 feet to the nearby combiner box.
I believe 121.38 (Voc) volts and 5.89 (Isc) amps of current will run to the combiner from each string.
I found a good source to find out if any inline fuse(s) and/or diode(s) will be needed as I connect my panels in series or proceed to the combiner.
diysolarforum.com/resources/fusing-wire-sizing-guidelines-for-solar-panels
Additional wire and connectors will be needed to reach the combiner. The farthest panel should be less than 25 feet from the combiner. I intend to use 8 or 10 awg solar cable, for a max 2% loss up to 26’. The wire will be of appropriate color and IP68 connections will be used whenever possible.
Shading of individual panels will never be an issue, unless I am standing there scratching my head.
THE COMBINER BOX:
MidNite Solar MNPV6 Combiner will be the last exterior component of the system.
At the combiner I will combine strings to up the voltage for the 55' run to the controller.
On the combiner box I believe the MidNite Solar MNSPD-300-DC 300V Dc Surge Protector Device would be a good idea.
Breakers being considered are manufactured for MidNite and limited to 150 volts.
Am I correct in assuming my breakers will be tripped by any voltage in excess of 150?
What about those sub-zero mornings? Will I be running outside to reset breakers sometime after sunrise?
If the breakers trip at 150+ volts, my charge controller should never experience “HyperVOC” or ever be subjected to any “OVERVOLTAGE” condition. Seems as though I am adding an additional level of protection for everything downstream. I’m good with that provided I am correct.
COMBINER OUT to CONTROLLER IN: 55'
Wires leaving the combiner will be in schedule 40 PVC conduit with 3 large radius 90 degree elbows throughout the entire run. The box will be mounted on and the conduit will pass through a 12” thick concrete wall and into a garage, across the ceiling of a bedroom (oh joy I get to do crown molding), into a very shallow attic and finally down into a closet to join the remaining components of the system.
The intent is to place the controller, batteries, inverter (not above batteries), gauges Etc. within a closet, with louvered doors, inside the living quarters of my residence. Can anyone think of a reason I should not do this?
My research leads me to believe up to 4 strands of 6 awg will live happily ever after inside ¾” conduit.
Using the initial panels, which I will not be using, and numbers from the MidNite Sizing Tool, which you can see below:
I am guessing between 102v and 150v depending on temperature and sunlight and up to 11.78 amps of current will be carried to my controller when the amps are at 100%.
On those hot days with minimum sun I need to get 102 volts 55 feet to the controller with minimal loss (2%). Again, research leads me to believe 6 awg will get almost all the volts there. I did look at a few wire/cable sizing sites and they produced conflicting numbers, so I am leaning towards 6 awg THHN THWN Stranded Copper Building Wire; Yes/No/Maybe?
I am living on the High Plains, I get snow, massive thunderstorms with a great deal of lightning, excellent sunshine, and a lot of 60+ mph winds. Larger panels are not really an option and these will be mounted pretty close to the ground with a lightning rod nearby.
How I got my numbers:
I used the Classic String Sizing Tool at midnitesolar.com/sizingTool/index.php
I could NOT figure out which numbers to plug into VOC or VMP Temp Coefficient boxes, so I left them set at default.
The solar panel manufacturer has these numbers on their website: It’s over my head folks.
Temperature Coefficient Of Voc -(80+/-10)mV/ (I am assuming the little “0” means “Degrees”)C
Temperature Coefficient Of Isc (0.065+/-0.015)%/ (assuming the little “0” means “Degrees”)C
Temperature Coefficient Of Power -(0.5+/-0.05)%/ (assuming the little “0” means “Degrees”)C
support.newpowa.com/support/solutions/articles/63000148010-npa100s-12h
Here are the other numbers from the manufacturers website. Amazon numbers differ from newpowa.com.
NPA100S-12H
Monocrystalline Module
ELECTRICAL CHARACTERISTICS
Type NPA100S-12H
Power Output(W) 100W
Voltage MPP Vmp(V) 17.0
Current MPP Imp(A) 5.89A
Voltage Open Circuit Voc(V) 20.23
Short Circuit Current Isc(A) 6.25A
Temperature Coefficient Of Voc -(80+/-10)mV/ C
Temperature Coefficient Of Isc (0.065+/-0.015)%/ C
Temperature Coefficient Of Power -(0.5+/-0.05)%/ C
NOCT (Air 20 degrees C; Sun 0.8kW/meters squared wind 1m/s) 47+/-2 degrees C
FINI
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