Installed a new 200 watt system on my van.

ericlp · May 17

I got a cheap knock off questionable mppt controller. So, far I am getting about 20 volts per panel... But, I am suppose to get 6.25 amps per panel. I have them wired in parallel. So, I am getting like 39 V and lucky to get 3 to 4 Amps in full sun... Altho, I only have one 100 amp hour renogy battery AGM.

My charge controller is a HQST 20 Amp ... Supposedly it's chinese made clone of the tracer brand. I haven't looked inside to see what kinda components are in it. This may be the problem. Some people say that I should wire the panels in series since, the charge controller wouldn't work so hard trying shove 40 volts into a 12 volt battery. Seems logical, but I have my doubts on this. If the charge controller is functioning as it would, should I see it go up to 6 amps? Or is it as good as it is going to get? I should say I had to use the entire 30' of 10 gauge wire that came with the kit. I have bought a remote mt-50 so, I can move the controller closer to the panels, and probably whack off 12 or so feet of wire. So, it would be about 20 feet of wire.

Thanks for any input... Pic of the unit is here.

https://photos.google.com/share/AF1QipMBONTTbnyGWTyE-tmcnfZ4VYaqQ5Cg0CFlGjpmV3UslUA44Oxp8Zdv_AYoWYRrVQ/photo/AF1QipPh7PwQpspXAM_DU7JWImMvayrDQHtJt3yHLE--?key=Vm5jNjI1aTA0dHJqdlFHNTItUFVvY3k3bkt3MGdB

Tecnodave · May 17

That sure looks like a EP Solar tracer or is it EPEVER now? I have had expereince with that type. If your panels are 36 cell "12 volt" panels then yes absolutely wire the panels in series. The minimum input voltage for that controller is a bit higher than those panels. Minimum input is more like 24-27 volts. These controllers transform that extra voltage into current at the battery. Think of it as an automatic transmission in your van....high voltage, low current in is transformed into lower voltage , higher current out to the batteries. This is the better choice for your installation. Try connecting in series and battery current will go up.....quite a bit......more like 12 amps or so

NOTE.....I gave up on EP Solar because they would not charge my high capacity solar batteries to full as these are programmed for some unknown "generic" battery as opposed to better controllers that are programmable to be an exact match to your battery manufacturers recommendation......I now only use MidNite as they are fully programmable.

seeing that EP Solar is a clone of a Morningstar , you have a clone of a clone........

littleharbor2 · May 17

Two things, Are your panels oriented correctly? You only get full current when pointed DIRECTLY at the sun. Try testing a panel's current with a multi meter. Very easy to see how orientation makes a big difference. Second. Are your batteries only lightly discharged when you see low current? The fuller they get, the less current they will accept.

You definitely need to series wire your panels.

Estragon · May 17

If you have ~20v per panel, and are getting 39v at the controller, the panels are wired in series, not parallel. In series, voltage adds and current (amps) stays the same. In series ~39v and 3-4a into an mppt controller sounds about right.

IMHO, an extra 12' of 10 gauge wire likely wouldn't make a huge difference in voltage drop, but could do interesting things if the extra is coiled up.

Tecnodave · May 17

Ericip,

on your comment of moving the controller closer to the panels.......don't, it is much better to have the controller closer to the batteries and have longer p.v. Input wires. It is critical that these controllers see the battery voltage with as little voltage drop possible. As I said they are not adjustable and the controller must "see" the battery voltage....best to run the controller wires directly to the battery rather than connect it to a junction of other wires going to the battery

ericlp · May 17

In a series circuit you sum the voltage of each panel to get the overall voltage of the array. However, the amperage of the overall circuit stays the same stays the same.

Yeah, I got that terminology backwards... Thanks...

So, I should keep them wired in series correct?

Yeah, Well, I'm definitely, not going to unbolt the panels just to orient them to the sun to see if they will indeed reach 6.25 Amps. I could do that at High Noon. Being mounted on a van without a tracker, I guess I am lucky to see 4 Amps for an hour. Even then... 4 amps X 40 V is only 160 watts out of the 200. Most of the time I get lucky to see 2 ~ 3 Amps on some days. That all depends pretty much on what angle the van is parked at and where the sun is. Pretty much just 80 -- 120 watts. I guess it's the price we all pay to surface mount the panels directly to the roof.

I only run a small dometic refrigerator, max air fan, and to charge up a laptop and cellphone. I'm hoping to charge up a 48V 14Ah E-bike battery, when there if FULL sun. We'll see how that works.

That is about 700 watts for the battery, I suppose even on a good day, with full sun for 5-7 hours it might be doable, or I could charge it half way one day, and the other half the next day.

I really don't want to invest more money in another 100AH battery, as in another year or two, I plan to swap it out for a 100Ah or 200Ah lithium type.

Thanks for your help!

ericlp · May 17

Tecnodave said:

That sure looks like a EP Solar tracer or is it EPEVER now? I have had expereince with that type. If your panels are 36 cell "12 volt" panels then yes absolutely wire the panels in series. The minimum input voltage for that controller is a bit higher than those panels. Minimum input is more like 24-27 volts. These controllers transform that extra voltage into current at the battery. Think of it as an automatic transmission in your van....high voltage, low current in is transformed into lower voltage , higher current out to the batteries. This is the better choice for your installation. Try connecting in series and battery current will go up.....quite a bit......more like 12 amps or so

NOTE.....I gave up on EP Solar because they would not charge my high capacity solar batteries to full as these are programmed for some unknown "generic" battery as opposed to better controllers that are programmable to be an exact match to your battery manufacturers recommendation......I now only use MidNite as they are fully programmable.

seeing that EP Solar is a clone of a Morningstar , you have a clone of a clone........

Nope it's definitely another clone of tracer...that renogy bought the rights from... and is pretty much cloned in a variety of chinese controllers that may or may not have the good internal wiring or components in them.. AKA a fake mppt controller.

https://www.hqsolarpower.com/v/vspfiles/Manuals/HQST-MPPT%2020-30-40.pdf

If you look on page 16 ... you can set the battery to USER and change any of those parameters... But you can only do so, if you buy a mt50 or get a usb part that fits correctly to a PC and find the software to talk to it. I have the MT50 to change the battery and other options like my controller was set to default 200 Amps that made it report funky battery status because I am only using 100Amps. Strange that they set them up that way, but I think the MT-50 was supposed to be sold along with these controllers, you can pick them up for 30 bucks on amazon.

Yeah, but, I'm a science guy, double the voltage or double the amperage ... doesn't matter how you slice it... your still going to come out with the same wattage. But if the controller will really produce 12 AMPS at 19 volts. Maybe it's worth buying the Parallel adapters from amazon to find out. If someone else can chime in that this is the case... I'll do it, but as I have stated in my previous post, these are FLAT mounted and bolted on to the roof of the van, there is no tilting racks or anyway to angle them. So.. I guess I should be happy with getting 70% of the rated watts out of them at best. I have a feeling that if I did wire them up Parallel I may get the 12 Amps but at 10 ~ 13 volts that would give me the same wattage in series.

Weather that 12 amps can be converted easier and sent down a 10 Gauge wire at 10~13 Volts to the battery vs. the charge controller trying to send down 2 ~ 3 amps down a 10 gauge wire at 39 volts is more effient one way or the other is another story.

Note my charge Controller is less than 2' from the battery.

I guess the only real way to find out would be to have two SET ups, with same panels, and controllers. One wired in series and the other wired in parallel and see what one may be more effient, if any. My gut tells me they will be the same.

Tecnodave · May 17

The EP Solar Tracers that I had did not have user settings, only preset for flooded or sealed. I did have the MT-50 remote, still not settable. I do not use generic automobile batteries, I have allways used large format FLA designed for the job at hand. Think of it this way, your automobile battery's job is to start the car, should do it in less than 15 seconds. It's job is done, it's going along for the ride. The car runs on the alternator. Solar is a different deal all togather when the sun sets its all on the battery, it had to stand on its own two feet, nobody to help for maybe 12 hours or so. I use L-16 format batteries and no Chinese controller has a proper charge profile for a true solar battery. My Rolls-Surette batteries are about $1600 delivered here and I won't risk them with a charge controller not designed for them, been there, done that, wasn't worth it. I spent more on fuel to run my gen set than the classic cost. Lesson learnt.

I gave up on them (Chinese controllers) years ago and bought stuff that the manufacturer supported, I called all the American controllers manufacturers and asked tough questions, mostly got scripted answers, but one company stood out way ahead of the others, on my first tough question to MidNite the call got transferred to boB , he was very precise in every answer. The next day I called wind sun and ordered the Classic 150.....no regrets, beautiful design, obviously designed by engineers for engineers.....never has a serious problem and when an issue popped up I got real people first call, superb technical advise, and a great forum with many enthusiasts I do not hire others to repair my gear, so I somewhat depend on manufacturers support. EP Solar had no support .period. Scripted answers that did not even relate to my issue. I now own dozens of MidNite products and look to them first. If they don't make it I look at American manufacturers first.
My choices, not nessecarily in order. ...MMMOSEC.......MidNite,MagnaSine,Morningstar,Outback,Schneider,Exeltech, Cotek.....All but one old times American companies, Cotek is Tiawanese but they support their product unlike Chinese product, at this point I will identify fault on offshore gear but will spend no effort trying to get it to work, just replace it.
hope you get better results than I did.

Note, my Rolls batteries will be 14 years old this month, they are doing just fine, MidNite Classic 150 is doing its job! Almost allways floating before noon.,
david

littleharbor2 · May 17

Besides orientation issues, being mounted on a van roof the heat in such a location is going to affect your output. Solar panels make more power when cold. If too hot a 12 volt parallel wired array won't make enough voltage to equalize a battery bank and barely enough to charge it. This is another reason you need to series wire the panels with an MPPT controller..

billybob9 · May 18

Looks like we're in the same boat. Since I'm 24v and have just install the

Image: https://us.v-cdn.net/6024911/uploads/editor/at/1vwa861fn1f3.jpg

Epever controller these are the stats on very week batteries
THE SYSTEM
Series 160W x 2 panels= 320W
Series 6V x 4 Batteries= 24V
Series 220AH X 4 =880AH
1500W Inverter
Load 48W Fridge 120AC, 15 minutes on / 45 minutes off

The 3.5A reading was taken when the fridge turned on. The only other loads were the Inverter and light in the fridge. Sunny day and test took 10 minutes. BG

Tecnodave · May 18

Amp hours of batteries in series do not add up 4 6 volt 220 amp hour batteries is a 24 volt 220 amp hour battery
watt hours do add up. 1 6 volt 220 ah battery is 1320 watt hours 1 24 volt 220 a.h. battery is 5280 watt hours

mountainman · May 18

@ericlp charge controllers have heat sinks on the back to cool. Heat rises and pulls cool air from the bottom. Yours will live a short life the way it is mounted.

billybob9 · May 18

Thanks Dave for the correction on AH and WH didn't get beat up too bad this time. Yeah, will change the controller for max venting, this was just a test and will be adding all my panels soon.

Plucka · May 20

I have 800 watts of solar panels on a flat roof of my van and the most I have got is 36 amps with mppt controller in mid summer but it was also in the mid 30C temperature.and I find on cold days [less than 25C] the panels put out less amps

Installed a new 200 watt system on my van.

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