Fridge on Solar?

[Techno]

It is still under warranty and the new circuit board they fitted last year never fully cured it.

 

[Peter A Forbes]

There's a bit of confusion over series/parallel connection of panels in this thread.

Most controllers have an upper input voltage limit to operate, and an even higher 'withstand' voltage which they can handle without damage, but for 12V operation you cannot series up two panels if you have the same controller as Andy and others have as its maximum MPPT voltage input is 33V.

Two panels in series on a good day will put out 18V each = 36V

Our two pairs of MPPT controllers are the same type.

Peter

 

[Techno]

The later model is 50 volts Peter
see table 1 page 9 EDIT sorry page 6!!
Broken Link Removed

 

[Peter A Forbes]

The later model is 50 volts Peter

That's the withstand, not the MPPT operating voltage.

"PCM3012 is an max 25A MPPTsolar charge controller with Maximum Power Point Tracking capability. It is designed for 12V battery system ONLY and can work well with many types of panels (max 50Voc, mppt range 15~37V). It is capable of supporting up to300W PV module with an maximum efficiency of 97%. It is suitable for operators of small, compact PV system who is looking to extract the MAXIMUM POWER from the PV modules. "

Peter

 

[Techno]

Yes 37 volts closed circuit not 33 as you quoted.
A pair of panels in series will be around 44 volts open circuit well inside the 50 volts

"Two panels in series on a good day will put out 18V each = 36V"

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[OldAgeTravellers]

Mine has been working very well for a year now with two panels in series in the south of France. They do produce a solid 36 volts most of the day but also produce enough to charge the batteries in much lower light conditions by being in series. My only problem is that as the panels are old the maximum output wattage had fallen a bit so I do not get the high current output that Andy gets. Very pleased with the controller which is much better than the original which killed a set of batteries.
Steve

 

[Peter A Forbes]

Yes 37 volts closed circuit not 33 as you quoted.
A pair of panels in series will be around 44 volts open circuit well inside the 50 volts

"Two panels in series on a good day will put out 18V each = 36V"

The early controllers that you and I have will be the 33V operating limit, later ones higher as per the quote I took from the item on ebay.

It isn't the withstand voltage that concerns me here, it's whether or not the system would run with panels in series.

You may recall my experiments with this on MHF where is wasn't effective at all?

Peter

 

[Techno]

I have the later ones and some time soon I'm going to connect one up on the deck when the weather returns.
I cannot do my own in series as I have 3 panels nor would I wish to.
I would say anyone who bought in the last 12 months has this model whether it be 200 or 300 watts

The old models do not have a back light

 

[Techno]

I cannot find version 1.1 but I have found version 1 instructions and that actually only operated between 15/22 volts so despite illustrating a series diagram it was not possible with 12 volt panels.

EDIT version 1.1 is also 15 to 22 volts
http://www.taiwantrade.com.tw/EP/re...0d-402d-988d-d63cb820ac9c_SCC-MPPT_manual.pdf

1.2 is the current model 15 to 37 volts

 

[Techno]

This video is really excellent in many ways for any one of any knowledge level, just found it myself and it focuses on the above unit.

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[Peter A Forbes]

I think our first is the earlier one with four battery types and no backlight. The second has the backlight and five battery types.

Last October's pair are the very latest with a pulsing float voltage.

Peter

 

[Pudsey Bear]

I think our first is the earlier one with four battery types and no backlight. The second has the backlight and five battery types.

Last October's pair are the very latest with a pulsing float voltage.

Peter

Hello, I didn't know you were on here too

 

[Techno]

Everyone is on here Kev

BTW I see you know Phil the fridge

 

[Pudsey Bear]

Yes, good lad, helped no end with the Laika fridge, ended up needing a new ignitor and a new selector thingy, although the selector only needed the contacts cleaning, which I've already had to do on the self builds fridge twice, crap design.

 

[Techno]

I have just connected a pair of panels to a 200 watt controller to one battery with a constant 47watt load (cool box)
Either in series or parallel the power output is exactly the same under the same sky only a few minutes apart. I tried with one panel covered in each case and no shading effect occurred only a reduction of 50%
I will post a new thread with pictures later. I would like to try it under a grey sky as this is where a series connection is meant to have the advantage.
Either way this controller accepts series configuration without issue.

EDIT
The solar has rapidly overtaken the load so with panels covered I will endeavour to bring the battery voltage down for a test later.

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[Techno]

I have just connected a pair of panels to a 200 watt controller to one battery with a constant 47watt load (cool box)
Either in series or parallel the power output is exactly the same under the same sky only a few minutes apart. I tried with one panel covered in each case and no shading effect occurred only a reduction of 50%
I will post a new thread with pictures later. I would like to try it under a grey sky as this is where a series connection is meant to have the advantage.
Either way this controller accepts series configuration without issue.

EDIT
The solar has rapidly overtaken the load so with panels covered I will endeavour to bring the battery voltage down for a test later.

http://www.motorhomefun.co.uk/forum/threads/mppsolar-mppt-regulator-parallel-or-series.106170/

 

[Peter A Forbes]

Interesting test, well done and timely in view of the discussions here.

Peter

 

[Peter A Forbes]

Hello, I didn't know you were on here too

Came on last November.

Peter

 

[Frasue]

Hi gents,

As an electrical illiterate, I've been reading this thread with a great deal more interest than understanding. I'm pretty sure my ignorance will be clearly displayed here, but hopefully one of the gurus could help me out? I've just installed a 250W panel and a Votronic DuoDigi MPPT controller with AES output on my Chausson Flash S3, supplying 2 x 110Ah leisure batteries and a trickle charge to the starter battery. All seems to be working fine so far, but it's driving me ever-so-slightly crazy whenever I see that AES light come on and I'm not using the 'excess' power available! I'm assuming that all the previous installations mentioned in this thread were AES fridges, but my fridge is a Dometic 7-series manual type which, when set to Battery mode, is (I think) only supplied from the engine battery/ alternator when the engine is running. The D+ wire is attached to a connector on the 12v distribution board. My question: is there any reasonably simple way that I could utilise the available AES signal to power the fridge (in Battery mode) from the leisure batteries? I'm thinking that a 'fake' D+ signal from the AES output to the dist. board D+ connector (diode in the 'true' D+ line? ), combined with a relay supplied by the Votronic's leisure battery outputs, controlled by AES output and feeding the fridge 12v supply might work? Yes, this is why I usually stick to hydraulics!
I'll try to attach the only wiring info I have for the van, and if anyone can suggest an elegant (or even workable) solution I'd be forever in your debt. (I realise I'd have to manually change from Battery to Gas whenever the AES wasn't available, but I'm not sure what would happen if I was to start the engine while AES was active and Fridge was on Battery...)

Thanks in advance and my apologies for that lengthy post -- technical writing isn't really my thang!