Wiring panels

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If I go with a PMW controller, and buy another panel, won't I have to buy 2 more panels if I'm running them in parallel?

Also, isn't it suggested and smarter to go with a MPPT controller once you get around 6 panels?
 
Oopslala said:
If I go with a PMW controller, and buy another panel, won't I have to buy 2 more panels if I'm running them in parallel?

Also, isn't it suggested and smarter to go with a MPPT controller once you get around 6 panels?

Your first statement puzzles me a little bit.  I'm guessing you're thinking of 6 volt batteries, where if you wanted to add more batteries, you'd need two more of them.  Each two 6 volt batteries would be wired together in series to make 12 volts, and each PAIR of wired together batteries would be hooked up in parallel.

As far as panels go, let's use some hypothetical panels as an example  If you had two nominal 12 volt panels that were putting out 10 amps at 18 volts, and you wired them in parallel, you'd 20 amps at 18 volts going into your controller.
Either an MPPT or PMW controller could be used, as long as it could handle 20 amps

If you wired them in series, you'd have 10 amps at 36 volts going into your controller, and you would NEED an MPPT controller to reduce the 36 volts down to something that could safely charge a 12 volt system.

If you added a THIRD panel, again all wired in parallel, you would have 30 amps at 18 volts.  If you added a third panel, all wired in series, you'd have 10 amps at 54 volts, and again an MPPT would be required.

Hope that's clear.

As far as your second statement, the way I hear it is, with parallel panels, an MPPT makes no financial sense until your system gets up to 500 watts or more.  The more watts your system has, the more "wasted" power an MPPT can salvage, and the more justified it's extra cost becomes. 

All of the above is based on 12 volt panels.  If you're using big "residential" panels at 36 volts or more, an MPPT is NECESSARY, regardless of whether you are wiring them in series or parallel.  If you wire them in series, you need to make sure the controller can handle the voltage, which is additive.  I see where Morningstar has come out with some Tristar models rated for 600 volts.  The older models were only rated for 150 volts.

Regards
John 

PS:  and yes, if you were running a LOT of panels, you could parallel two separate strings of panels wired together in series, and in THAT case you'd need even numbers of panels so that the voltage from both strings matched.  NOT a situation we're likely to run into on vans and rvs.
 
Optimistic Paranoid said:
Your first statement puzzles me a little bit.  I'm guessing you're thinking of 6 volt batteries, where if you wanted to add more batteries, you'd need two more of them.  Each two 6 volt batteries would be wired together in series to make 12 volts, and each PAIR of wired together batteries would be hooked up in parallel.

As far as panels go, let's use some hypothetical panels as an example  If you had two nominal 12 volt panels that were putting out 10 amps at 18 volts, and you wired them in parallel, you'd 20 amps at 18 volts going into your controller.
Either an MPPT or PMW controller could be used, as long as it could handle 20 amps

If you wired them in series, you'd have 10 amps at 36 volts going into your controller, and you would NEED an MPPT controller to reduce the 36 volts down to something that could safely charge a 12 volt system.

If you added a THIRD panel, again all wired in parallel, you would have 30 amps at 18 volts.  If you added a third panel, all wired in series, you'd have 10 amps at 54 volts, and again an MPPT would be required.

Hope that's clear.

As far as your second statement, the way I hear it is, with parallel panels, an MPPT makes no financial sense until your system gets up to 500 watts or more.  The more watts your system has, the more "wasted" power an MPPT can salvage, and the more justified it's extra cost becomes. 

All of the above is based on 12 volt panels.  If you're using big "residential" panels at 36 volts or more, an MPPT is NECESSARY, regardless of whether you are wiring them in series or parallel.  If you wire them in series, you need to make sure the controller can handle the voltage, which is additive.  I see where Morningstar has come out with some Tristar models rated for 600 volts.  The older models were only rated for 150 volts.

Regards
John 

PS:  and yes, if you were running a LOT of panels, you could parallel two separate strings of panels wired together in series, and in THAT case you'd need even numbers of panels so that the voltage from both strings matched.  NOT a situation we're likely to run into on vans and rvs.

Ah, I misunderstood parallel panels.  I was under the impression they were essentially "paired" in doubles.  Now I understand it though.  I definitely have been planning on wiring them parallel though.  

I plan on getting between 4-6 100w renogy panels now that I've determined I'll run the fridge/freezer on propane, so MPPT might still be something to consider, depending on how much I lose because I don't have one.  Once I get over 4 panels wired in parallel, I'd have to upgrade to the 60 amp morning star PMW charger? I'm going to assume it wouldn't be smart to put 6 panels on a 60 amp charger?
 
Oopslala said:
Ah, I misunderstood parallel panels.  I was under the impression they were essentially "paired" in doubles.  Now I understand it though.  I definitely have been planning on wiring them parallel though.  

I plan on getting between 4-6 100w renogy panels now that I've determined I'll run the fridge/freezer on propane, so MPPT might still be something to consider, depending on how much I lose because I don't have one.  Once I get over 4 panels wired in parallel, I'd have to upgrade to the 60 amp morning star PMW charger? I'm going to assume it wouldn't be smart to put 6 panels on a 60 amp charger?

I'm not sure what panel you're planning to use, but I looked at one Renogy 100 watt panel whose specs were 18.4 volts at 5.29 amps  (which multiplies out to 97.336 watts).  So if you're only talking 6 amps per panel, then 6 panels would provide 36 amps, which a 45 amp controller should handle easily.  No particular reason to upgrade, unless you think you might want to add even more panels down the road, in which case I suppose it wouldn't be a bad idea to put the 60 amp in now.

Regards
John
 
I'm still tying to decide on 4 or 6 panels. I think I'll go with 4, but wire for 6, that way I can expand if 4 isn't enough power.

Now that I actually did some number crunching, the price of 4 is a lot more feasible than the price of 6. At least buying all of the system at once.

As for the charge controller, I'm just gonna pay the little bit of extra money and go with the tristar 60 amp in case I really expand in the future.
 
So I think I've got my solar system all figured out, at least what I want to get anyways

Morningstar 60Amp Tristor Charge Controller PWM https://www.shopakari.com/Morningst...S9MusPnwNEMti09wFzhDBNSB-LlcYr9VfWBoCmvnw_wcB

4 Trojan T-105 6V Deep Cycle Golf Cart Batteries http://www.trojanbattery.com/product/t-105/

Bogart Trimetric TM-2030 http://www.altestore.com/store/Mete...dMeOQk_WSM3tDgjnOnDRr_dUi75-AEKMwfxoCvyXw_wcB

500 amp shunt (dont know which one yet, will take suggestions)

Inverter (need to get pure sine and plan on running a microwave, so i'll take suggestions what inverter you guys use, please)

4 Renogy 100w Panels http://www.amazon.com/RENOGY®-Monoc...pebp=1437231960259&perid=1QMH3W4T08F7RDA4KTEG

Renogy 20 ft Adapter Kit http://www.amazon.com/RENOGY®-Adapt...keywords=20+ft+adapter+kit+solar+cable+renogy

Renogy Z Brackets http://www.amazon.com/Renogy-Solar-...pebp=1437232104523&perid=02CHFWF7PCZD0ZYY1XN0

Branch Connector http://www.amazon.com/RENOGY®-Branc...pebp=1437232149404&perid=0QX7RBHB9M2RTD2ZATCH

I know I'm missing quite a bit of stuff that I'll need, like fuses/fuse box, connectors, wiring etc. but I'm not 100% sure what I need at this point in that department, hence why I'm asking.

I plan on having 4 solar panels right now, but may upgrade in the future to a maximum of 6 renogy 100w panels, so I plan on wiring for 6 right now. I will be running them in parallel (obviously) so I'm guessing I'll need more connectors than listed above.

If someone would kindly tell me everything I may need and missed in the list above, that would be greatly appreciated!!
 
Too late to edit again, damn.

The more I think about it, the more it seems like it might be better to go with MPPT and pay the extra $150 roughly, just so I have it, and can run series if I ever may need to. It also would be a lot easier to do a combiner box before it goes into the CC, should save a lot of trouble.

Would a combiner box go up on top of the RV with the panels, or go next to the CC inside?
 
Oopslala said:
Inverter (need to get pure sine and plan on running a microwave, so i'll take suggestions what inverter you guys use, please)

Read this blog post by Handy Bob:  https://handybobsolar.wordpress.com/inverter-issues-spring-2013/  Pay particular attention to his comments on high voltage cut out of 16.5 volts vs 15 volts.

Based on this article, I bought a Samlex Pure Sine with the 16.5 volt high voltage cut out.  http://www.amazon.com/Samlex-2000W-...r=8-4&keywords=samlex+pure+sine+wave+inverter

If you buy it from Amazon, do please go through Bob's site.

Regards
John
 
Oopslala said:
Too late to edit again, damn.

The more I think about it, the more it seems like it might be better to go with MPPT and pay the extra $150 roughly, just so I have it, and can run series if I ever may need to.  It also would be a lot easier to do a combiner box before it goes into the CC, should save a lot of trouble.  

Would a combiner box go up on top of the RV with the panels, or go next to the CC inside?

The best combiner boxes I've seen come from A M Solar.  http://www.amsolar.com/home/amr/smartlist_16/rv_roof_combiner_boxes.html  Good educational articles on this site, too.

You don't HAVE to do your combining on the roof, but if you don't, and you wire multiple panels in parallel, you will have multiple wire to get through the roof in a waterproof manner.  Then use bussbars like these: http://www.solar-electric.com/installation-parts-and-equipment/midnite/brbusbatebus.html  to combine them inside near your controller.

Regards
John
 
My combiner boxes consist of a large blue wirenut filled with AL-OX and covered with liquid tape.Placed under the panels and at least 2 in. off the roof.Of course,I'm cheaper than most people.
 
Selecting the components is easy, it's connecting them all together that's the hard part. Each component will have directions, download these and start connecting things up on paper. Depending on their placement and usage, you'll end up with a mismatch of terminal and wire sizes. You'll need some terminal lug crimpers as well.
 
Oopslala said:
So I think I've got my solar system all figured out, at least what I want to get anyways

Morningstar 60Amp Tristor Charge Controller PWM https://www.shopakari.com/Morningst...S9MusPnwNEMti09wFzhDBNSB-LlcYr9VfWBoCmvnw_wcB

4 Trojan T-105 6V Deep Cycle Golf Cart Batteries http://www.trojanbattery.com/product/t-105/

Bogart Trimetric TM-2030 http://www.altestore.com/store/Mete...dMeOQk_WSM3tDgjnOnDRr_dUi75-AEKMwfxoCvyXw_wcB

500 amp shunt (dont know which one yet, will take suggestions)

Inverter (need to get pure sine and plan on running a microwave, so i'll take suggestions what inverter you guys use, please)

4 Renogy 100w Panels http://www.amazon.com/RENOGY®-Monoc...pebp=1437231960259&perid=1QMH3W4T08F7RDA4KTEG

Renogy 20 ft Adapter Kit http://www.amazon.com/RENOGY®-Adapt...keywords=20+ft+adapter+kit+solar+cable+renogy

Renogy Z Brackets http://www.amazon.com/Renogy-Solar-...pebp=1437232104523&perid=02CHFWF7PCZD0ZYY1XN0

Branch Connector http://www.amazon.com/RENOGY®-Branc...pebp=1437232149404&perid=0QX7RBHB9M2RTD2ZATCH

I know I'm missing quite a bit of stuff that I'll need, like fuses/fuse box, connectors, wiring etc. but I'm not 100% sure what I need at this point in that department, hence why I'm asking.

I plan on having 4 solar panels right now, but may upgrade in the future to a maximum of 6 renogy 100w panels, so I plan on wiring for 6 right now.  I will be running them in parallel (obviously) so I'm guessing I'll need more connectors than listed above.  

If someone would kindly tell me everything I may need and missed in the list above, that would be greatly appreciated!!

Branch connectors and panel mounts come with the kit...
 
Bob Dickerson said:
My combiner boxes consist of a large blue wirenut filled with AL-OX and covered with liquid tape.Placed under the panels and at least 2 in. off the roof.Of course,I'm cheaper than most people.

With Renogy branch connectors, he won't need a combiner box.
 
where's all the Renogy posters. I haven't seen them comment in a while. highdesertranger
 
Oopslala said:
So I think I've got my solar system all figured out, at least what I want to get anyways

Morningstar 60Amp Tristor Charge Controller PWM https://www.shopakari.com/Morningst...S9MusPnwNEMti09wFzhDBNSB-LlcYr9VfWBoCmvnw_wcB

4 Trojan T-105 6V Deep Cycle Golf Cart Batteries http://www.trojanbattery.com/product/t-105/

Bogart Trimetric TM-2030 http://www.altestore.com/store/Mete...dMeOQk_WSM3tDgjnOnDRr_dUi75-AEKMwfxoCvyXw_wcB

500 amp shunt (dont know which one yet, will take suggestions)

Inverter (need to get pure sine and plan on running a microwave, so i'll take suggestions what inverter you guys use, please)

4 Renogy 100w Panels http://www.amazon.com/RENOGY®-Monoc...pebp=1437231960259&perid=1QMH3W4T08F7RDA4KTEG

Renogy 20 ft Adapter Kit http://www.amazon.com/RENOGY®-Adapt...keywords=20+ft+adapter+kit+solar+cable+renogy

Renogy Z Brackets http://www.amazon.com/Renogy-Solar-...pebp=1437232104523&perid=02CHFWF7PCZD0ZYY1XN0

Branch Connector http://www.amazon.com/RENOGY®-Branc...pebp=1437232149404&perid=0QX7RBHB9M2RTD2ZATCH

I know I'm missing quite a bit of stuff that I'll need, like fuses/fuse box, connectors, wiring etc. but I'm not 100% sure what I need at this point in that department, hence why I'm asking.

I plan on having 4 solar panels right now, but may upgrade in the future to a maximum of 6 renogy 100w panels, so I plan on wiring for 6 right now.  I will be running them in parallel (obviously) so I'm guessing I'll need more connectors than listed above.  

If someone would kindly tell me everything I may need and missed in the list above, that would be greatly appreciated!!
You're going to need a 30 amp fuse between the you're going to need a 30 amp fuse between the panels and controller, and a 30 amp between the controller and battery. You'll need the cables from the controller to the batteries, as well as cable to connect the batteries to each other. You'll need wire strippers, a crimper, round cable connectors - but most parts come with the kit. Not pushing my own skills, but check the solar install thread I did on this kit.  I got a lot of good advice there, that you may find helpful. It shows photos of everything. Don't forget Renogy has video instructions on their site, which are great.
 
Seraphim, I'm aware that the kit does come with everything I'd need. I don't plan on buying the kit, instead just panels and everything that would come with the kit apart from the charge controller, where I'll get a morningstar instead. I'll save roughly $300 on the panels/branch connectors and brackets etc going that way.

I've read HandyBob's site 3 times. It's just a lot to take in, I'll be sure to check out where you're talking about though.

My dad owns a farm, so he may have all the tools I'll need to do the wiring. I'm not sure if he deals with wiring this big though, so the crimpers may be way too small.

I'll definitely be checking out renogy's instructions.
 
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