Portable solar charging setup I just built...

[billy_gr]

really nice to be a member of CPF

I made the same assumption... but when i look on some cheap 120Watt panel... the Voc was 40 Volts...

After a bit of more searching most of the 120Watt panels have an open voltage of around 20-22Volts so this could be the maximum for this type of controllers.

240Watt goes up to 30-40 volts so it is a no go

I don't want to buy a controller for a 40-60 Watt panel and then after an upgrading the system with a bigger panel buy again a new controller...

Thanks for the info, keep up posted with the process

 

[SemiMan]

Some controllers will naturally current limit thought most PWM will not. 12V nominal (20-22VOC) panels above 120W are rare, but you can always put two together. Most 80W panels have a short circuit current in the 4.5 - 5amp range so it would be dicey with two not to violate the specifications of a 10amp controller, especially since the short circuit current goes up as the panels heat up.

Of course you are only going to hit that peak for a brief period per day.

You can get a 240W panel, you just need an MPPT controller instead of a PWM controller.

Semiman

 

[Norm]

Norm quick question what is the maximum panel that you can use with this controller ?

I am gathering some info for a similar project (to drive some LED lamps) but the Voc vs Watt per panel cause me headache...

Bill

Just found this page Best Deals Morningstar SHS-10 Solar Controller 10 Amp 12 Volt 170 Watts.

Specifications:

Solar Current: 10A / 170 Watts

Load Current: 10A / 170 Watts

System Voltage: 12V

Low Voltage Disconnect: 11.5V

Low Voltage Reconnect: 12.6V

Norm

 

[ChrisGarrett]

Just found this page Best Deals Morningstar SHS-10 Solar Controller 10 Amp 12 Volt 170 Watts.

Specifications:

Solar Current: 10A / 170 Watts

Load Current: 10A / 170 Watts

System Voltage: 12V

Low Voltage Disconnect: 11.5V

Low Voltage Reconnect: 12.6V

Norm

That's basically the SunSaver 10-L made for the non-Canadian/US markets as your link states. The housing and terminal blocks are different, but the operating specs appear to be identical.

30w panel appear to output at ~1.75A, if you go by the ratings sticker on most of these panels.

My two 30w mono crystaline panels are ~1.75 amps, each, so 60w gets me ~3.5A in a laboratory. Double that for 7A, throw in another 30w and 1.75A and we're just below 9A at 8.75A. Shave off a third from the sixth 30w panel and you're at 170w and almost 10A, for the unit's max.

Fun with math.

10A would be nice, but I'm cool at 3.5A for my battery charging needs.

People don't realize, but these bigger glass paned panels get heavy, if you need things to be mobile, or semi-portable, so keep that in mind. Plus, they start to get unwieldly, if you have to move them around.

Chris

 

[Norm]

Like most thing I do Chris, the controller is overkill I know :devil:

Norm

 

[Norm]

A bit more work today, I mounted my controller directly to the panel with Anderson Powerpoles on the output.

Norm

 

[ChrisGarrett]

A bit more work today, I mounted my controller directly to the panel with Anderson Powerpoles on the output.

Norm

Looks good! Your controller seems to be more in line with the Gen 3 SS-10L, which has the battery SOC indicator LEDs on it.

I should have gotten that one, but it didn't work out and that's why I keep a DMM in my charger/battery box, lol!

Chris

 

[Norm]

I'd just like to thank you guys for convincing me to upgrade my controller, tried charging with the cheap controller, when the controller had finished charging I put the battery on the ctek and it continued to top off the battery for about an hour, same exercise with new controller and the ctek told me the battery was completely charged.

Norm

 

[SemiMan]

That is what we are here for

I am glad you made the investment.

I have designed a fairly sophisticated MPPT controller and evaluated numerous cheap to mid end controllers and spent too many an hour reviewing algorithms, test fixture data and real world data. Many controllers are not very good unfortunately.

 

[NeedMoreLight]

So if someone is using a charger like the Nitecore i4 which can be plugged into a 12 volt car cigarette lighter socket, how much wattage/amperage would one need for solar panels to do the same thing? I see some panels with a 12 socket and controller already installed and made me curious.

 

[ChrisGarrett]

So if someone is using a charger like the Nitecore i4 which can be plugged into a 12 volt car cigarette lighter socket, how much wattage/amperage would one need for solar panels to do the same thing? I see some panels with a 12 socket and controller already installed and made me curious.

I'm not an EE, or gizmo designer, but if you look at your 12v adapater, it will give you the current output and that gives you an idea. Remember, most batteries that you charge up aren't completely empty, so you're not 'spending' your solar power, or mother battery power, completely achieving the listed capacity number on the cell.

Also and I may be wrong here, but most of these chargers use a pulse current to charge, so they're not charging all 4 cells at full current at any given point in time, they're rapidly rotating from bay to bay and back again.

Finally, there are 'inefficiencies' to this stuff. PWM controllers lose a little bit of power regulating the solar panels and chargers lose a little bit of power charging up batteries...it's never 100% in, 100% out.

A good 'rule of thumb' for me is, is that I'm going to lose 25%, either from my solar panels, or my mother batteries.

So if I need 4Ah to fill my batteries up to 100%, I'll need 5Ah of juice from the mother battery, or solar panels.

That's how I look at it, anyhow, but I'm an English Lit/Comm. major.

Chris

 

[Wiggle]

I'm considering doing something like this and looking to buy local since shipping seems quite expensive for these type of items. A local seller has some stuff here: http://halifax.kijiji.ca/c-buy-and-...eries-Too-W0QQAdIdZ373716295QQfeaturedAdZtrue

Do these seem like alright prices? I was looking at getting the 40 watt panel, the 10A controller and the 120 Ah battery.

 

[ChrisGarrett]

I'm considering doing something like this and looking to buy local since shipping seems quite expensive for these type of items. A local seller has some stuff here: http://halifax.kijiji.ca/c-buy-and-...eries-Too-W0QQAdIdZ373716295QQfeaturedAdZtrue

Do these seem like alright prices? I was looking at getting the 40 watt panel, the 10A controller and the 120 Ah battery.

His prices aren't bad. I see $199 CD + tax and shipping for the 90w panel and they are mono-crystaline, so pretty efficient. If you're going with 40w, then you'll be spending less. I don't know that brand of controller, but it looks full featured, if it isn't junk. I didn't see a price on that, but my Mornintstar SS 10L above, was $70 shipped. My two 30w mono panels and 2 Y connectors were $178 shipped, from California to Miami, as a reference and I could have saved maybe $20 off of that, had I done the seller's Ebay auctions instead of the package deal.

A 120Ah SLA/AGM is a big honking battery for sure. I just bought a 22Ah Chrome battery for $46 shipped to go along with my initial 12Ah PowerSonic and they're made here in Indiana, US and get good marks. They market a $238 US (shipped) 110Ah SLA/AGM here:

http://www.chromebattery.com/12v-110ah-sealed-lead-acid-sla-battery-m8-t8-terminals.html

but I don't know if they ship out of the US.

Depending on what you'll be running off of the 120Ah battery, you might want to try and swing the 90w pannel for ~$200, as the mother battery will charge that much faster.

As I've mentioned, I have about $400 in my kit and kaboodle, but I view it as a nice little insurance policy that will last for a while and at least keep me illuminated at night, should the power go out for a longish period of time, like it's wont to do here in Miami during hurricane season.

Chris

 

[SemiMan]

I'm considering doing something like this and looking to buy local since shipping seems quite expensive for these type of items. A local seller has some stuff here: http://halifax.kijiji.ca/c-buy-and-...eries-Too-W0QQAdIdZ373716295QQfeaturedAdZtrue

Do these seem like alright prices? I was looking at getting the 40 watt panel, the 10A controller and the 120 Ah battery.

Thoughts:

- Panel's may be monocrystalline, but at this quality level, that is meaningless. Many polysilicon cells are more efficient than many mono cells. Look at the label on the panel: "Solar Mooule". So much care they did not even include the D in module. No meaningful certifications (CSA is only special inspection .... pretty much useless). Summary --- no name crap and the price is about what one would pay for no name crap.

- Charge controller: More no name crap. Don't waste your money on it, even if it is free as your batteries are not!

- Batteries: More crap .... It's an Everstart 27DC-850N from Walmart. Poor quality. I would be very concerned about how long these have been sitting without being charged. They could be sulfating already. That 120AH is a stretch. Maybe at a really low discharge rate. Flooded deep cycle cells require maintenance to get long life. Don't expect real long life out of it. They are selling it cheaper than Walmart ... so again, I expect these have been sitting around for a while.

- The people selling it: ... you know the word I am going to use. I watched the installation video ..... scary. They call themselves electrical people? .... NOT. The guy has no clue what he is doing or saying for that matter. I would not reward them with your money.


Semiman

 

[Wiggle]

Thanks for the assessment. Little disappointed as it was a convenient local source but since it seems that the quality is not up to par I will pass.

 

[Norm]

Getting on with my Battery Box build.

​

Charge discharge Amps / Voltage / battery % / capacity in Ah all in the one meter, fuse, four USBs, four Anderson Power Pole connectors and yet to be added two cigarette light sockets (you can see the two pilot holes also have to add a LED indicator next to the USBs. Most bits are just sitting in the panel for the photo.

Lift the panel out to reveal, jump starter and battery charger storage.

​

Norm

 

[ChrisGarrett]

Looks great Norm! Keep us posted when the project is done.

Chris

 

[Norm]

OK I have a new addiction, now I want to build a set up to run my HAM shack.

Looking at this controller

30A MPPT Solar Panel Regulator Charge Controller 12V/24V 380W/760W With LCD USB

I've only gone with 30 A as that would cover my maximum peak load and I would like to use the output from the charger rather than direct from the battery as I'm doing with my portable set up. Any other controller suggestions would be welcomed, Chris you have convinced me that the controller is just as important as any other component, so I'm willing to pay for the right controller. I like the information available using this controller.

I just bought a 130W of mono panel.

Norm

 

[ChrisGarrett]

Norm, I'm no expert on MPPT controllers, but when I was researching the PWM versions, I came across MPPTs and some of the big players, like Morningstar, Blue Sky, Rogue, Midnight Solar, Xantrex, Outback FM and some others. Prices were generally up and over US $300 and many of the smaller load versions were up over $200, so that one in your link, I don't know how good it is?

I think it's SemiMan that might be able to comment on that brand, since he has stated that he's built them before and he's in the commercial 'solar game' IIRC.

In the gun hobby, we have a saying: 'Buy right, buy once, cry once'.

Chris

 

[Norm]

OK, I bought another Morningstar model SS-20L-12V 12Volt 20Amp DC Solar Controller with LVD, would have liked a 30A but 20A will do the job OK.

Received my 135W mono panel, need to buy some Aluminium channel to mount it on the roof, and some cable to wire things up.

Norm