Answered

my solar setup


Posted by raydas

Aug 15, 2019 at 8:29am

*****A disclaimer, this thread contains material and discussions that is "...dangerous and not productive...". I guess that warning should satisfy everybody.
*****

Since I am new here, I thought I would just describe my setup first.


Basically, I have six panels, four 100W and two 50W, connected in parallel to my Rover MPPT controller. I also have two batteries, flooded car and 100AH deep cycle SLA, in parallel. The load connecter from the Rover goes to a distribution strip where I have at least five electronic devices that are being powered. According to the 'Solar Station Monitor', the amps that are being used by these devices is .80Amps, 24 hours a day, continuously.


The solar panels are outside, at ground level, propped up against an exterior wall, facing maybe 80 degrees in the direction of the sun. I know, perpendicular to the sun is what is needed, but that is in the best of conditions. Two 100W are facing east, two of the 50W are facing SE, moveable to face SW, as the sun moves during the seasons. The last two 100W are facing due south. Here in Michigan, we have snow to deal with, so these panel positions do not get covered with snow.

I can describe this setup as experimental, since I am trying to collect data, to get an idea of how the solar panels work, for my different requirements. So far, for the summer months, with a mix of lots of daylight hours, and some cloudy, rainy days, it seems like the batteries and power produced can handle the power load that I have right now. I am thinking about adding an inverter to the system to power my Dell server box and my Western Digital MyCloud NAS, which have four 10TB drives, to the system. Not sure if my setup will be able to handle those two units.

The other thing that I was thinking about is that I might have to add a battery charger, that would kick in when the batteries get to low. This would occur, in the winter months when you only get maybe four hours of good sunlight, and you have a week or more of snow/cloudy days. It would be nice if Renogy had a controller that had a battery charger component. That means that you would be able to plug wire into the wall socket, and the controller could figure out if and when to use the 110V power to drive the built in charger, to charge up the batteries.

I did have an experimental setup where I had a Deltron Batterry Tender Plus connected to the battery and one of my electronic boards setup to turn on/off the charger when the batteries went below 12V. That experiment disclosed that the battery charger was always taking over when the Rover should of been providing the power. Could not find a suitable solution for that problem.

Thanks for taking the time to read this.

Posted by raydas

Aug 15, 2019 at 11:59am

Yesterday there was a larger update to the Windows 10 computer, now it looks like my 'Solar Station Monitor' program is acting funny. A couple of times that I looked at it, it kept showing that the program was not responding. Not sure if this has something to do with the latest Windows update or what.

Since the 'Solar Station Monitor' program is no longer supported by Renogy, I guess an alternative program, that can be kept up to date, is in order. I guess I will ask it here, is the command set available for communicating with the Rover via RS232/USB, available somewhere.

Posted by raydas

Aug 15, 2019 at 2:17pm

Another thought, since Renogy is no longer supporting the 'Solar Station Monitor' program, has Renogy considered open sourcing the program code. Not sure what language the program is written and compiled in, but their could be some useful information that could be used by everybody.

Posted by mediadogg

Aug 16, 2019 at 5:24pm

OMG, where to start (it probably doesn't make sense to try and discuss all of my points here. I suggest to find the other threads where they are already discussed, and also do some Google research before asking me "why ..." or to justify in detail. The ground has already been covered.):

(1) Having mismatched panels in parallel limits the higher capacity panels to a maximum output voltage of the smaller panels. Given your geography and installation, my recommendation would be to put the 4 x 100 panels in series on your existing controller, and buy a small additional controller with the 2 x 50 watt panels in series on it. The two controllers can feed your battery bank simultaneously, in parallel.
(2) Don't try to use the load output of the charge controller for anything other than light, non-inductive loads. Not worth the aggravation and risk of damage to your controller. Connect your loads, appropriately fused, directly to the battery.
(3) Yes, Renogy and many other companies make what are called "inverter / chargers", that can work in cooperation with a solar CC. Just connect the battery to both, in parallel. The inverter/charger automatically switches to battery when it is charged, or to the AC mains when the battery is low and being charged. During the day, a parallel connected solar CC helps keep the battery charged. (some companies also make an all-in-one that include a solar CC along with a built-in AC charger, but as you already have your CC, you don't need that.)

Follow these suggestions, and you will be on the road to creating an even more effective and usable system. You will get other ideas from others and add your own good ideas as you learn, but I think I have given you a couple of good places to start exploring.

Posted by tattoo

Aug 16, 2019 at 6:19pm

mediadogg Avatar

Aug 16, 2019 at 5:24pm mediadogg said:

 (2) Don't try to use the load output of the charge controller for anything other than light, non-inductive loads. Not worth the aggravation and risk of damage to your controller. Connect your loads, appropriately fused, directly to the battery.


Now your talking...... If the load side was intended for running more than just lights people wouldn't have so many problem with it.....

Posted by raydas

Aug 17, 2019 at 5:21am

As a reminder, my setup is basically a test rig. I set it up with the knowledge that I had about solar stuff at the time. As I get more facts then I will be changing things around, for example, the use of the Load.

I am now considering how to switch from the Load to the battery array, directly. Should I consider finding a large DC-DC voltage regulator to put between the battery array and the power strip. The electronic things that are now being powered, have there own DC-DC voltage regulator. Some devices need 5V and some devices need 9V, and so on.

As for the comment about "mismatched panels in parallel", I am still thinking about that one. I am trying to figure out, how, in an efficient way, I can capture the functional data of each individual panel. I can already capture the data for the total array. The data meaning strictly the voltage, I was looking into some device to capture the actual working amps and possibly watts. The stuff available was to complicated for me to install, in a workable manner, in my test rig.

Posted by tattoo

Aug 17, 2019 at 6:01am

raydas Avatar

Aug 17, 2019 at 5:21am raydas said:

 Some devices need 5V and some devices need 9V, and so on.


Where are you finding this stuff?? 5v really?

Posted by tattoo

Aug 17, 2019 at 6:16am

raydas Avatar

Aug 17, 2019 at 5:21am raydas said:

 I can capture the functional data of each individual panel. The stuff available was to complicated for me to install, in a workable manner, in my test rig.


Why do you need to know what each panel is producing?


I think your making it more complicated than it really is.......

Posted by mediadogg

Aug 17, 2019 at 6:21am

tattoo Avatar

Aug 17, 2019 at 6:16am tattoo said:

raydas Avatar

Aug 17, 2019 at 5:21am raydas said:

 I can capture the functional data of each individual panel. The stuff available was to complicated for me to install, in a workable manner, in my test rig.


Why do you need to know what each panel is producing?


I think your making it more complicated than it really is.......


Oh I so totally agree!!!!

Posted by mediadogg

Aug 17, 2019 at 6:31am

raydas Avatar

Aug 17, 2019 at 5:21am raydas said:

As a reminder, my setup is basically a test rig. I set it up with the knowledge that I had about solar stuff at the time. As I get more facts then I will be changing things around, for example, the use of the Load.

I am now considering how to switch from the Load to the battery array, directly. Should I consider finding a large DC-DC voltage regulator to put between the battery array and the power strip. The electronic things that are now being powered, have there own DC-DC voltage regulator. Some devices need 5V and some devices need 9V, and so on.

As for the comment about "mismatched panels in parallel", I am still thinking about that one. I am trying to figure out, how, in an efficient way, I can capture the functional data of each individual panel. I can already capture the data for the total array. The data meaning strictly the voltage, I was looking into some device to capture the actual working amps and possibly watts. The stuff available was to complicated for me to install, in a workable manner, in my test rig.


Maybe you should tell us what your application is. What is this "power strip?" And what do you have plugged into it.

I have to be honest and say that it sounds as if you have some misguided and poorly researched plans. But I might be wrong, and I will admit it, if I discover that from looking at your application - what you are trying to do, and why - the equipment being powered, etc.

The panel specifications are published, often right on a sticker on the back. You don't have to measure anything to set them up. But you would benefit from a little reading about how things work, and how to use basic electronics to configure your system. There is a lot of good basic information, right on this web site,

But could you just back up and tell us, in detail, what you are trying to do?

Posted by tattoo

Aug 17, 2019 at 6:38am

mediadogg Avatar

Aug 17, 2019 at 6:21am mediadogg said:

Oh I so totally agree!!!!


Man I don't understand why people want to over think solar.... It's not complicated...... My system is as simple as any it gets....... And it runs flawlessly................


I look at my digital volt display in the AM just to make sure the batteries are ok and I don't look at it intentionally until the next morning....... Why bother it's working?? Do people also keep up with how much AC power is coming into there house?? No, so why worry about solar??


Now with that said, Yes if your having problems sure look at it...... But if you know something your doing is a known problem change it....... It doesn't matter how much you swap things around your going to have the same outcome..... Unless you do something totally different......


I just don't understand.......

Posted by raydas

Aug 17, 2019 at 6:46am

Since I have my panels in three different areas, it would be nice to know what the panels are producing in terms of Volts. If and when I get a chance I might try to get some data as to what the panels are doing when you have it in its optimal position, perpendicular to the sun, and how the efficiency deters as the panel is moved away from the perpendicular. I have not seen that data for the Renogy panels.

So, in other words, short of having the panels in perpendicular position, for the location, what would be the next best orientation that I could come up with. I think that kind of data is very important, unless I find out that the panels are a hundred percent efficient at any orientation.

Posted by mediadogg

Aug 17, 2019 at 7:07am

raydas Avatar

Aug 17, 2019 at 6:46am raydas said:

Since I have my panels in three different areas, it would be nice to know what the panels are producing in terms of Volts. If and when I get a chance I might try to get some data as to what the panels are doing when you have it in its optimal position, perpendicular to the sun, and how the efficiency deters as the panel is moved away from the perpendicular. I have not seen that data for the Renogy panels.

So, in other words, short of having the panels in perpendicular position, for the location, what would be the next best orientation that I could come up with. I think that kind of data is very important, unless I find out that the panels are a hundred percent efficient at any orientation.


Well you have a done a good job of memorizing some solar buzzwords and jargon. But you are throwing them around in a meaningless way that reflects your basic lack of understanding of how things work. Once again I suggest that do a few hours of study "How does a solar system work" "what is a solar panel and  how does it work" "what is a charge controller and what does it do", etc. Also, until you show some kind of diagram, or give some kind of explanation of what you are trying to do, I will not spend much more time in this thread. I would like to help you, but you are not listening and not ready.

Posted by tattoo

Aug 17, 2019 at 8:10am

raydas Avatar

Aug 17, 2019 at 6:46am raydas said:

Since I have my panels in three different areas, it would be nice to know what the panels are producing in terms of Volts. If and when I get a chance I might try to get some data as to what the panels are doing when you have it in its optimal position, perpendicular to the sun, and how the efficiency deters as the panel is moved away from the perpendicular. I have not seen that data for the Renogy panels.


And you won't get it from anyone as that kind of data is useless,,,,, Because it changes EVERYDAY every hour of the day depending on where you live...... Unless your planning on building or buying one of those setups that move across the sky with the sun, that data is no help what so ever....... Other than making it even more complicated.... And if you did or could get it, what will it help you with your load hooked to the load side of your CC and getting error codes? As long as it's hooked up that way your going to have problems.....

Posted by tattoo

Aug 17, 2019 at 8:17am

mediadogg Avatar

Aug 17, 2019 at 7:07am mediadogg said:

 Also, until you show some kind of diagram, or give some kind of explanation of what you are trying to do, I will not spend much more time in this thread. I would like to help you, but you are not listening and not ready.


Yep I'm very close to that point also.......


The way I look at it, if your not willing to listen to the answer to your question why ask it in the first place..... If you know the answer already, DO it don't talk about it.....


 



Posted by raydas

Aug 17, 2019 at 8:52am

Thanks for all the information so far, guys, I will keep pursuing this in my own way.

Posted by bupkis

Aug 17, 2019 at 8:55am

raydas Avatar

Aug 17, 2019 at 6:46am raydas said:

Since I have my panels in three different areas, it would be nice to know what the panels are producing in terms of Volts. If and when I get a chance I might try to get some data as to what the panels are doing when you have it in its optimal position, perpendicular to the sun, and how the efficiency deters as the panel is moved away from the perpendicular. I have not seen that data for the Renogy panels.

So, in other words, short of having the panels in perpendicular position, for the location, what would be the next best orientation that I could come up with. I think that kind of data is very important, unless I find out that the panels are a hundred percent efficient at any orientation.


easy to read panel volts right on the lcd of the rover while in bulk/'mppt' mode (in operation) or you can test them with an amp meter while changing the angle. renogy.boards.net/thread/159/solar-panel-troubleshooting
sun angle does change voltage but not as much as sun angle jacks with power (if volts doesn't change then that other component amps does). Power is what should be compared.
Good ole Pythagorean Theorem can be used to calculate the perpendicular component of angled sun. power reduction from heat is based on the specs of the panel and panel temp. Renogy usually has a download 'specs' on their panels that shows this, often reported as NOTC, like www.renogy.com/content/files/Specifications/RNG-100D-SS%20spec.pdf

this guy has done some of the calculations with results for whole day/season, not just a moment in time.
www.solarpaneltilt.com/

Posted by raydas

Aug 17, 2019 at 9:10am

The solarpaneltilt.com looks like the information that I was seeking. I guess I have to get better in phrasing my query on the internet.

With that information, I can do away with the tedious job of wiring and data collection. Now I have to check all of the wires in my contraption setup. Some of the wires were getting hot to the touch, wires are not handling the current as I would of hoped. One thing about this solar stuff, some new problem always pops up, at least for the beginner.

Posted by tattoo

Aug 17, 2019 at 9:52am

raydas Avatar

Aug 17, 2019 at 8:52am raydas said:

Thanks for all the information so far, guys, I will keep pursuing this in my own way.


Now that sounds like a plan.....


But I do wish you would post a diagram of your system to see if we could help you.......

Posted by mediadogg

Aug 17, 2019 at 10:13am

raydas Avatar

Aug 17, 2019 at 9:10am raydas said:

The solarpaneltilt.com looks like the information that I was seeking. I guess I have to get better in phrasing my query on the internet.

With that information, I can do away with the tedious job of wiring and data collection. Now I have to check all of the wires in my contraption setup. Some of the wires were getting hot to the touch, wires are not handling the current as I would of hoped. One thing about this solar stuff, some new problem always pops up, at least for the beginner.


Geez ... why don't you just study it? You don't have to hope. There is tons of info on wire size, fuse ratings, panels wiring configurations, etc. The moment you told us that you paralleled 50W panels with 100W panels, I knew you were in trouble. Hearing paralleling a wet lead acid with SLA was another caution point. Now, hearing "hot wires" spells big danger. I highly recommend - STOP right now and do some research before you hurt yourself. Take advantage of, now 3 offers to help you, if you would just share more about what you are doing. Your response has been "never mind, I'll just keep doing it my way." Then why did you come here in the first place?

Posted by tattoo

Aug 17, 2019 at 11:40am

mediadogg Avatar

Aug 17, 2019 at 10:13am mediadogg said:

  I highly recommend - STOP right now and do some research before you hurt yourself.


Or even worse burn your house down........ I'm not sure at this point if he has fuses , breakers or any safety features.....

Posted by russ

Aug 17, 2019 at 12:12pm

raydas Avatar

Aug 15, 2019 at 8:29am raydas said:

Since I am new here, I thought I would just describe my setup first.


Basically, I have six panels, four 100W and two 50W, connected in parallel to my Rover MPPT controller. I also have two batteries, flooded car and 100AH deep cycle SLA, in parallel. The load connecter from the Rover goes to a distribution strip where I have at least five electronic devices that are being powered. According to the  'Solar Station Monitor', the amps that are being used by these devices is .80Amps, 24 hours a day, continuously.


I recommend using the four 100 watt panels in series (as Mediadog suggested) with your Rover charge controller, provided it is a Rover rated at 30 or 40 amps. I would set up the 400 watts of solar panels in series and the Rover charge controller to charge your 100 Ah deep cycle battery. With wiring appropriate for the voltage and current the panels can produce.

Because the flooded car battery is mismatched to the deep cycle battery they shouldn't be connected in parallel, I would set it (the flooded car battery) up separately with the two 50 watt solar panels as a separate system. To set up the flooded car battery as a independent system you obtain another MPPT charge controller, or PWM if you get one capable of handling the combine voltage of the two 50 watt panels and connect the two 50 watt panels in series. Otherwise, you could connect the two 50 watt panels in parallel and connect them to a less expensive PWM charge controller to charge the flooded car battery.

This would give you two systems that would work more efficiently than the way that you have it now.

I would also face all the panels south because you are in the northern hemisphere. And determine the best angle above horizontal to place them. Depending upon your solar panel mounting, you might change the angle every few months to improve the output of the panels as the seasons change.

What size and length of wire are you using? By putting the four 100 watt panels in series you lower the current requirements of the wiring from the panels to the charge controller.

I realize that you are experimenting, but I would think that part of that would be in an attempt to build the system to work as efficiently as possible. I take it you are collecting data to determine how much power you can reliably use from the solar power equipment you are working with?


Posted by tattoo

Aug 17, 2019 at 1:43pm

^^^^^^^^^^^ That's damn good info right there......^^^^^^^^^^

Posted by mediadogg

Aug 17, 2019 at 1:49pm

Absolutely. Great info russ!!!

Posted by raydas

Aug 17, 2019 at 1:56pm

My latitude is 42.48*. Yes, I am trying to determine the solar usable power aspect of my setup.

My reasoning for panels in parallel, in the winter and the panel distribution, there is about 3 maybe 4 hours of good workable sun, of course, when it is not cloudy or snowing. So, my setup would be producing, maybe 10Amps. I think I need high amps in order to get the best charge on the batteries for the given time limit. I know there is charge time factor involved with charging the battery.

The electronics that I have connected, so far, are:
Raspberry Pi 3, has a DC-DC 5V regulator rated at about 2 Amps, using the GPIO pin connection.
Parallax Activity Board WX, power input can handle up to 26V.
2 Parallax Activity Board, power input needs 6-9V, can pick up using the USB connetion.

The Parallax Activity Board WX has a WX module plugged in which provides a WiFi capability. The board also has 4 ADC ports which I have connected to the flooded battery, 100AH battery, the panel array, and the two panels that I have facing East. I also created an .html file that I can view on a browser screen. This works because of the WX WiFi module. This program displays the battery voltage, array voltage, outside temp/humidity, and inside temp/humidity at my solar CC and such. Plus it gives me an idea of what the temp/humidity is in the room. The temp/humidity modules are dht22.

As soon as I get a good idea as to how much power my two batteries can provide, I will be adding more stuff to the system.

Posted by tattoo

Aug 17, 2019 at 2:50pm

raydas Avatar

Aug 17, 2019 at 1:56pm raydas said:

As soon as I get a good idea as to how much power my two batteries can provide, I will be adding more stuff to the system.


I say your there right now with those small batteries..... Anything else and you will be digging a hole.......


You need to remember you can ONLY use 50% of your flooded battery....

Posted by tattoo

Aug 17, 2019 at 2:59pm

raydas Avatar

Aug 17, 2019 at 1:56pm raydas said:

  there is about 3 maybe 4 hours of good workable sun, of course,


 It's all workable sun from dawn to dusk...... My batteries are at 12.7 3 hours before the sun ever gets over the trees and gets full direct sun to my panels...... In the summer I was lucky to get 2 and a 1/2 hours of direct sun because of the trees........ I now get another 1/2 hour or so now that I have added the 4 extra panels....


Your really over thinking this.......

Posted by bupkis

Aug 17, 2019 at 3:21pm

raydas Avatar

Aug 17, 2019 at 1:56pm raydas said:

My latitude is 42.48*. Yes, I am trying to determine the solar usable power aspect of my setup.

My reasoning for panels in parallel, in the winter and the panel distribution, there is about 3 maybe 4 hours of good workable sun, of course, when it is not cloudy or snowing. So, my setup would be producing, maybe 10Amps. I think I need high amps in order to get the best charge on the batteries for the given time limit. I know there is charge time factor involved with charging the battery.


you do not understand what an mppt controller does!
PWM controllers are forced to use parallel connected '12v' panels.
Mppt controller can accept higher voltage input power and transform it to charge a 12v battery.
Voltage drop is based on amps, so the benefit of series connected panels will reduce voltage drop using the same size wire.

Take 400w input @ 17v x 23.5A. The controller transforms this to battery charging power or 400w
Take 400w input @ 34v x 11.76A. The controller transforms this to battery charging power of 400w
Take 400w input @ 68v x 5.88A. The controller transforms this to battery charging power of 400w

ignoring eff, all three above charge the battery the same!

If all three above use the same size wire, there is one configuration that has the smallest voltage drop (power loss).

paralleling pairs of series panels is a good compromise unless the wire run is excessive.
you can't use the 2 50w panels with that configuration.

Posted by mediadogg

Aug 17, 2019 at 3:36pm

bupkis Avatar

Aug 17, 2019 at 3:21pm bupkis said:

raydas Avatar

Aug 17, 2019 at 1:56pm raydas said:

My latitude is 42.48*. Yes, I am trying to determine the solar usable power aspect of my setup.

My reasoning for panels in parallel, in the winter and the panel distribution, there is about 3 maybe 4 hours of good workable sun, of course, when it is not cloudy or snowing. So, my setup would be producing, maybe 10Amps. I think I need high amps in order to get the best charge on the batteries for the given time limit. I know there is charge time factor involved with charging the battery.


you do not understand what an mppt controller does!
PWM controllers are forced to use parallel connected '12v' panels.
Mppt controller can accept higher voltage input power and transform it to charge a 12v battery.
Voltage drop is based on amps, so the benefit of series connected panels will reduce voltage drop using the same size wire.

Take 400w input @ 17v x 23.5A. The controller transforms this to battery charging power or 400w
Take 400w input @ 34v x 11.76A. The controller transforms this to battery charging power of 400w
Take 400w input @ 68v x 5.88A. The controller transforms this to battery charging power of 400w

ignoring eff, all three above charge the battery the same!

If all three above use the same size wire, there is one configuration that has the smallest voltage drop (power loss).

paralleling pairs of series panels is a good compromise unless the wire run is excessive.
you can't use the 2 50w panels with that configuration.


YES!!!!

And by the way, raydasthis post has some info about handy DC-DC converters.

Posted by russ

Aug 17, 2019 at 11:48pm

raydas Avatar

Aug 17, 2019 at 9:10am raydas said:

The solarpaneltilt.com looks like the information that I was seeking. I guess I have to get better in phrasing my query on the internet.

With that information, I can do away with the tedious job of wiring and data collection. Now I have to check all of the wires in my contraption setup. Some of the wires were getting hot to the touch, wires are not handling the current as I would of hoped. One thing about this solar stuff, some new problem always pops up, at least for the beginner.


Which wires are getting hot to the touch? Solar panels to batteries? Charge controller to batteries? The wires connecting the batteries in parallel?


As Bupkis pointed out, you can reduce the wire size requirements between the solar panels and the charge controller if the solar panels are in series. Which is normally the longest wire run in a solar power system.


You should not be connecting mismatched batteries in parallel. A flooded car battery and a 100 AH deep cycle battery have different charging characteristics. They should be in separate systems.



Posted by russ

Aug 18, 2019 at 12:17am

raydas Avatar

Aug 17, 2019 at 1:56pm raydas said:

My latitude is 42.48*. Yes, I am trying to determine the solar usable power aspect of my setup.

My reasoning for panels in parallel, in the winter and the panel distribution, there is about 3 maybe 4 hours of good workable sun, of course, when it is not cloudy or snowing. So, my setup would be producing, maybe 10Amps. I think I need high amps in order to get the best charge on the batteries for the given time limit. I know there is charge time factor involved with charging the battery.


At full sunlight, if you have all four 100 watt panels in parallel facing south, and at the correct angle, (and your battery system needs charging) you should be getting up to 18 amps at around 17 volts to the charge controller. If you have all four panels in series, which a 30 or 40 amp Rover can handle, you should be getting up to almost 5 amps at around 68 volts.


18A x 17V = 320 Watts (about 80% of 400 watts)


4.7A x 68V = 319.6 Watts


If the wire run from the solar panels is 20 feet then 10 AWG wire is adequate for 4.7 amps. (AWG = american wire gauge)


For 18 amps with a 20 foot run of wire you are going to need 1/0 AWG wire.


If the wire run from the solar panels to the charge controller is longer than 20 feet, you are going to need thicker wire than stated above.


Unless you have problems with shading or mounting locations, there is no advantage to facing your panels in different directions and wiring in parallel.





Posted by bupkis

Aug 18, 2019 at 5:50am

so above it suggested 10awg x 4.7A x 20' yielding a voltage drop of .193v www.genuinedealz.com/voltage-drop-calculator
So the power loss is .193 X 68v or 13 watts panels to CC.

@ 17v, 13 watt loss = .765 volts, redo v.d. for 18A x 20' yields v.d. or .739v or ~13 watts!
The CC will operate more eff transforming 17v vs 68v esp at low power conditions.

The problem with using single parallel panels is panels get hot and Vmp drops.
Paired series panels (w/mppt cc) solves that by doubling Vmp to >30v les v.d.

Posted by raydas

Aug 18, 2019 at 6:13am

The reason I have my panel pairs in different locations is because of shading. I will probably try to angle the panels at 55*, this will be about the best angle for a winter angle and probably an all year position.

Yesterday I noticed that some of the wiring going into the CC was getting very hot, never noticed that before, so today I have to rethink my wiring, and try to rewire if I have the materials.

In the conversations so far I have noticed that you guys are using fuses, I do not have any fuses anywhere. I made an assumption that the CC would handling that issue.

At this point it sounds to me like their would be a need for a solar station fuse box. The wire from the panels going in, passing through breakers, going to the CC. The wire coming out of the CC going to the box, passing through breakers, going to the battery. And maybe somewhere in there some terminal connections for accessing some regulated power, OK now I am awake.

Posted by mediadogg

Aug 18, 2019 at 6:43am

raydas Avatar

Aug 18, 2019 at 6:13am raydas said:

The reason I have my panel pairs in different locations is because of shading. I will probably try to angle the panels at 55*, this will be about the best angle for a winter angle and probably an all year position.

Yesterday I noticed that some of the wiring going into the CC was getting very hot, never noticed that before, so today I have to rethink my wiring, and try to rewire if I have the materials.

In the conversations so far I have noticed that you guys are using fuses, I do not have any fuses anywhere. I made an assumption that the CC would handling that issue.

At this point it sounds to me like their would be a need for a solar station fuse box. The wire from the panels going in, passing through breakers, going to the CC. The wire coming out of the CC going to the box, passing through breakers, going to the battery. And maybe somewhere in there some terminal connections for accessing some regulated power, OK now I am awake.


Once again, you are substituting guesswork and assumptions for plain old study. There is so much information on the topic of putting together a DIY solar system, that there is no excuse for the things you don't seem to know or understand. Not all of the information out there is correct, but there is enough, so that you can soon begin to see what is "generally accepted" as the right way to do things, and tested alternatives to fit certain situations. You don't have to guess. There are enough things that can go wrong, even when you plan carefully, that there is no excuse for bumbling around. The fact that you did not realize that you need fuses confirms to me that, while you seem smart enough and capable enough to do this stuff, you do not seem to recognize the value of properly educating yourself to maximize the power of your capabilities, and minimize the chance of dangerous mistakes. I know that I am speaking harshly. But if it saves your life, I don't mind if you don't like me.

Posted by tattoo

Aug 18, 2019 at 6:46am

raydas Avatar

Aug 18, 2019 at 6:13am raydas said:

 Yesterday I noticed that some of the wiring going into the CC was getting very hot, never noticed that before, so today I have to rethink my wiring,


You need to rethink your entire system not just the wires........ It's getting hot because something is done wrong.......


Heck you have several things done wrong.....


You need to turn it off and start all over before you burn something up.............


I know the above was wasted words because you know way better what your doing than anyone else, but I felt that it needed to be said again....

Posted by tattoo

Aug 18, 2019 at 6:49am

raydas Avatar

Aug 18, 2019 at 6:13am raydas said:

 In the conversations so far I have noticed that you guys are using fuses, I do not have any fuses anywhere. I made an assumption that the CC would handling that issue.



 


No fuses? ? ? Really? ? I'm not surprised......

Posted by tattoo

Aug 18, 2019 at 6:53am

tattoo Avatar

Aug 17, 2019 at 11:40am tattoo said:

Or even worse burn your house down........ I'm not sure at this point if he has fuses , breakers or any safety features.....


Yep just as I thought.......... NO FUSES..........


That's not very smart,,,,,,,,,,

Posted by russ

Aug 18, 2019 at 8:22am

bupkis Avatar

Aug 18, 2019 at 5:50am bupkis said:

so above it suggested 10awg x 4.7A x 20' yielding a voltage drop of .193v www.genuinedealz.com/voltage-drop-calculator
So the power loss is .193 X 68v or 13 watts panels to CC.

@ 17v, 13 watt loss = .765 volts, redo v.d. for 18A x 20' yields v.d. or .739v or ~13 watts!
The CC will operate more eff transforming 17v vs 68v esp at low power conditions.

The problem with using single parallel panels is panels get hot and Vmp drops.
Paired series panels (w/mppt cc) solves that by doubling Vmp to >30v les v.d.


With 68 volt input about 13 watts loss due to voltage drop with 10 AWG wire at 20 feet.


With 17 volt input about 13 watts loss with 1/0 AWG wire at 20 feet.


Yes, at the higher voltage input the MPPT charge controller will loose something like 2 to 4 percent efficiently.  As long as you can afford the cost of larger wire, connecting four panels in series parallel is more efficient.

Posted by tattoo

Aug 18, 2019 at 8:27am

raydas Avatar

Aug 18, 2019 at 6:13am raydas said:

  I made an assumption that the CC would handling that issue.
 


You do know what assume means? ? ? ?

Posted by russ

Aug 18, 2019 at 8:37am

raydas Avatar

Aug 18, 2019 at 6:13am raydas said:

The reason I have my panel pairs in different locations is because of shading. I will probably try to angle the panels at 55*, this will be about the best angle for a winter angle and probably an all year position.

Yesterday I noticed that some of the wiring going into the CC was getting very hot, never noticed that before, so today I have to rethink my wiring, and try to rewire if I have the materials.

In the conversations so far I have noticed that you guys are using fuses, I do not have any fuses anywhere. I made an assumption that the CC would handling that issue.

At this point it sounds to me like their would be a need for a solar station fuse box. The wire from the panels going in, passing through breakers, going to the CC. The wire coming out of the CC going to the box, passing through breakers, going to the battery. And maybe somewhere in there some terminal connections for accessing some regulated power, OK now I am awake.


The rover manual includes information for determining what size fuse your system should have between the solar panels and the charge controller, and between the charge controller and the battery. The Rover charge controller will not protect against excessive current or and accidental short circuit. Excessive current can damage your charge controller. An accidental short circuit of the battery leads can vaporise the wiring, and in the case of the flooded battery, can cause a hydrogen oxygen explosion. You should take the time to read the safety information in the Rover owners manual. Although it may seem boring, it would be time well spent.


This illustration is if you connect all four panels in series. Although this illustration doesn't show a fuse in line with the inverter, I would recommend installing one appropriate to the size of the inverter.


Take a look at this illustration to get an idea about fuse placement:

Posted by russ

Aug 18, 2019 at 8:40am

raydas Avatar

Aug 18, 2019 at 6:13am raydas said:


Yesterday I noticed that some of the wiring going into the CC was getting very hot, never noticed that before, so today I have to rethink my wiring, and try to rewire if I have the materials.


What size and type of wire is going into the charge controller, and how long is it?

Posted by tattoo

Aug 18, 2019 at 8:43am

russ Avatar

Aug 18, 2019 at 8:40am russ said:

raydas Avatar

Aug 18, 2019 at 6:13am raydas said:

Yesterday I noticed that some of the wiring going into the CC was getting very hot, never noticed that before, so today I have to rethink my wiring, and try to rewire if I have the materials.


What size wire is going into the charge controller, and how long is it?


You know another question would be is...... What kind of wire is he using? ? ? Since he's using what he has on hand......

Posted by raydas

Aug 18, 2019 at 9:05am

Since I have six panels, I have 12 wires coming in, and I have a fairly heavy duty terminal block where the wires are connected. At one end of the terminal block I have two diodes, one on the +, and one on the -, that plug into a quick connect. The other side of the quick connect I have the two wires going into CC panel connect. The diodes, if I remember correctly are rated at 30Amps/1000V. So at this quick connect point, I guess, I will be able to contrive some kind of fuse connection.

I am also using a quick connect between the CC and the battery, for a quick disconnect of power. I guess the quick connect could be a place for the fuse.

This morning I noticed that the CC was showing 7.68Amps from the panels, and the battery array was at 13.2V. So, I did a disconnect of the panels and after about an 1.5 hour time lapse, I checked the battery voltage and that was 12.8V.

I looked outside at the panels, this morning, and my east facing panels, 2 100W, h

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