Size of a controller for 4x100 watt renogy solar panels.

[SunPoweredInternet]

Looking at upgrading my under powered system, only things I keep is inverter and batteries. Want to have potential for 4 X100 Watt panels max and see the tracer 3215 has 30 amps which is good but says pv max of 390 W so my question is can I assume the loss in wire and connections will bring the ideal "400 watts" of panels to an acceptable level as to not fry the controller the next size up is 40 amp and that is 500 W 12 volt. I would like my load output and batteries to be 12 V so trying to stick with that. I already made the mistake of buying a 10 amp tracer with the MT-5 so I can at the very least use the MT-5 meter if I stick with the tracer brand.

Thanks in advance for your assistance!

[Mike90250]

STOP
before you buy anything, see what a couple of 250 to 350W panels would cost you ? possibly less than 40 100w panels would. Take that extra cash and get a real MPPT controller to step down the 40V from the panels, to your 12V batteries.
Why you are still using 12V is a different topic.

[SunPoweredInternet]

STOP
before you buy anything, see what a couple of 250 to 350W panels would cost you ? possibly less than 40 100w panels would. Take that extra cash and get a real MPPT controller to step down the 40V from the panels, to your 12V batteries.
Why you are still using 12V is a different topic.

Hello you may remember me from my previous post, my number 1 post, I just have the 2 wireless antenna. I agree 400 watts is probably too much. My plan is to start with a pair of 100 W panels and just have a controller big enough to support more if needed, As for the 12 volt question, if I make those 2 12 volt panels to 24 and feed it to the controller don't I in turn have to have my load coming off the controller at 24 volts? Then wouldn't I need something to step it back down to 12, I need to run my craptastic 100W inverter that is plugged into a cig lighter right now. I use the load and timer on the controller at the moment and can monitor it through the MT-5 meter which is a nice feature for me.

So basically the 4 x100 watt panels would be a "maybe someday" if I have to leave the current config where it is at to make up for the dang trees that block the sun, I am in discussions with the neighbors to cut some down so that may get me an extra hour of light a day which would be great.

So that being said would the 30 amp 12/24 volt controller work?

I believe you and another member thought 300 Watts would be where I would need to be, which at 12 volts I could add a 3rd one at some point to hit that 300W goal. The 150 Watt panel is about $200 and the 100 watt are $124 and a 250 is about $300. I am an amazon prime shopper for the most part so maybe there are some better deals out there. We unfortunately don't have a solar shop around here so this is how I need to get my materials. Unless you count the menards stuff or farm and fleet.

Trying not to spend a fortune for my internet setup here but the load is pretty small the 2 plus are only consuming 1 kw between the 2, the inverter fan is probably sucking more.

Thanks for sharing your information.

[ButchDeal]

you would not get the full capacity from 4x100w modules with a pwm controller. You may also find that a single 250w modules is cheaper than two 100w modules.
and further that two 250w modules are cheaper than 4 100w modules (and much less than 5 100w). with enough savings to get a decent MPPT controller.
resulting in a 12V system that can be easily upgraded to 24V.....
I think if you look here you might find lots of 250w+ modules for ~$250 and that was barely looking....

http://www.wholesalesolar.com/solar-panels

[SunPoweredInternet]

you would not get the full capacity from 4x100w modules with a pwm controller. You may also find that a single 250w modules is cheaper than two 100w modules.
and further that two 250w modules are cheaper than 4 100w modules (and much less than 5 100w). with enough savings to get a decent MPPT controller.
resulting in a 12V system that can be easily upgraded to 24V.....
I think if you look here you might find lots of 250w+ modules for ~$250 and that was barely looking....
http://www.wholesalesolar.com/solar-panels

The tracer 3215 is an 30 amp MPPT controller, http://voile.org/panneaux_solaires/Tracer-3215RN.pdf, I will do some shopping around for panels as well, my last post had responses that said shoot for 300 watts and up to 25 amps so I thought I was heading in the right direction. I will keep researching. Thanks.

[SunPoweredInternet]

you would not get the full capacity from 4x100w modules with a pwm controller. You may also find that a single 250w modules is cheaper than two 100w modules.
and further that two 250w modules are cheaper than 4 100w modules (and much less than 5 100w). with enough savings to get a decent MPPT controller.
resulting in a 12V system that can be easily upgraded to 24V.....
I think if you look here you might find lots of 250w+ modules for ~$250 and that was barely looking....
http://www.wholesalesolar.com/solar-panels

This is the MPPT controller I am looking at http://voile.org/panneaux_solaires/Tracer-3215RN.pdf , I was told in a previous thread to go for 300 watt system so a 250 could only be expanded with another 250 that would most probably be serious overkill for my little setup, I am only bumping the panels from the 3-30 watt panels that worked all summer until the last few weeks because the sun is dropping so I only get a few hours of sun a day now so need to pump up the input when I have the sun.

Thanks

[SunPoweredInternet]

Not sure why, I am trying to respond to your response ButchDeal and it keeps saying unapproved. The controller I am looking at is a MPPT 30 amp controller, it might be the link so I will just put this info in "Tracer-3215RN —— Maximum Power Point Tracking Solar Charge Controller" if you search that you can find the manual. Anyway I was shooting for 300 watts total based on previous post so thought if I could get a big enough controller for a 4th if I need it someday great. I am having tree issues now that the days are shorter and the sun in going down on the horizon a bit.

If I do a 250 and it is under powered I would need to buy another 250 to be able to attach it to the system correct to hit or surpass my 300 mark and at that point I would have a much larger investment and would need get the next size up controller. 40 amp version. Right?

[ButchDeal]

because of the link, delete it in a quote.

That tracer CC at 30amp can handle 390w of input at 12V, if you put the two 250W modules in an East/West arrangement you can get them on the controller. That 390W input on the CC is actual input, not STC.
It would give a longer power curve this way.

Or you could get one of the larger modules like a 315w for $300,

[Logan5]

All internet equipment I am aware of already runs from DC power. Why use an inverter at all?

[SunPoweredInternet]

All internet equipment I am aware of already runs from DC power. Why use an inverter at all?

I agree this is very true, the switch with PoE that would be able to run on direct 24 volt was very expensive. The device not only has to power the 2 aps but serve as the bridge. if you know of a product that is reasonably priced and available please pass it along. Thanks

[Logan5]

If your battery bank is already 24v, run your 24 volt load direct or with an inline voltage regulator, $20 to 50 bucks, for your 12 volt loads, use a simple step down converter $20 to 50 bucks. Make sure you are running both terminal fuses as well as distribution fuses. If your battery is only 12 volts, replace with a new 24 volt battery bank. Running an inverter for such a small load, makes the inverter it's self the majority of the load. get rid of the inverter and simplify the setup. I have done this and it can be done.

[Logan5]

I have a Rocket M2 and it runs from 11 to 30 volts, you may not need 24 volts at all, either way 24 volts offers real power and ensures the system is over sized to maintain loads thru winter months.

[jflorey2]

All internet equipment I am aware of already runs from DC power. Why use an inverter at all?

Important note - many devices (like USB hubs) rely on the galvanic isolation that an AC/DC wall wart provides. Removing that can be risky, and can result in ground loops. These can cause problems ranging from audio noise to physical damage.

[Logan5]

I guess some of the equipment I have scrapped in the past were victims of this phenomenon. I have several thousand dollars of equipment that I have mitigated from wall warts to a stabilized DC UPS, two DVR's, three ATSC modulators, active head end combiner, ethernet switches, and routers. For mission critical devices, if it does not run from my UPS, then it does not meet my requirements and goes into the Radio flee market box.

[SunPoweredInternet]

From what I can tell I currently use between 26 and 30 amp hours per 24 hour period with the 100W inverter and using the 110 bricks provided by Ubiquiti, it does sounds silly to go from 12 volt to 110 just to go to 24 volt and I am sure loss is present but that challenge is for a different day I think. The 300w of panels and 30 amp controller should help keep my VMAX tanks charged better. I originally under powered EVERYTHING and am totally aware of that, I am learning as I go I didn't have ton invested in my first setup and it will still work to keep my camper battery powered over winter, so it won't go to waste.

Camswitch has a 24 volt PoE switch but it retails for about 300 something and looking at it, will pull 4 amps since so right now the cheapo cig lighter 100w inverter will be in place for a while yet.

Thanks again all, everything I learn here is valuable information, we can't all be electrical engineers but still want to use solar.

[Logan5]

I can get a cheap passive POE inserter and divider for less than 10 bucks. and nicer units for less than 20. forget the Ubiquity brick, the POE brick they come with forces you to supply 110v, get rid of it or hand isolate your POE pair and bond them yourself.