Mppt solar charge controller ?

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dunkelly

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Ok I was dumb enough to believe that e bay would not allow products to be missadvertised. I foolishly bought one of the cheap "mppt" controllers that keep draining the battery . But that is all in the past so the question is what size controller do I need for 3 X 20 watt solar panels and I would appreciate a recommendation as to a reasonably priced alternative , if there is one .! Many thanks
 
A manufacturer of genuine MPPT controllers is Epever. They are sold under their own name on ebay and Amazon or as other brands by companies like Photonic Universe. The model Jamie Dundee points to is a branded Epever product. They are not the cheapest, but cheap MPPT controllers on ebay are fakes. They say MPPT on the outside but are PWM on the inside. There are many videos on youtube where these cheapies are dismantled and shown to be fake. A good indication is the size and weight. If it's small and light it won't have the hefty coil inside that the genuine MPPT ones need.
 
The small Victron MPPT chargers are very good. There are differences between controllers even if you eliminate deceptive products.

The the 75/10 is about £100, so may be outside the budget, but is worth considering.
 
I'm more than pleased with my epever. Works really well and has all sorts of menus in it.
It was of the few electronic that survived a drenching when my exhaust fractured.
 
dunkelly said:
Ok I was dumb enough to believe that e bay would not allow products to be missadvertised. I foolishly bought one of the cheap "mppt" controllers that keep draining the battery . But that is all in the past so the question is what size controller do I need for 3 X 20 watt solar panels and I would appreciate a recommendation as to a reasonably priced alternative , if there is one .! Many thanks
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I have a victron 75 15 mppt to charge 2x100 amps batteries through 2x100w solar panels changed from a cheap chinese one
that only lasted 2 years of course lots of sunshine in Greece
 
PaulRainbow said:
Not as much as that:

Victron Energy BlueSolar MPPT 75/10 - SCC010010050R – Battery Megastore
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That link is for the older and I think discontinued “Victron Blue solar 75/10” rather than the current “Victron Smart solar 75/10”.
I would not recommend buying the older version. The extra features of the Smart solar version are generally worth the price difference unless the budget is very tight. The £100 pound price I quoted is just a general guide for the price of the Smart Solar 75/10 . I would expect it can be found cheaper with some careful shopping.

If you do have an older “Blue solar” Victron controller there is an add on dongle availble from Victron that adds some (unfortunately not all ) of the features of the Smart solar models.
 
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noelex said:
That link is for the older and I think discontinued “Victron Blue solar 75/10” rather than the current “Victron Smart solar 75/10”.
I would not recommend buying the older version. The extra features of the Smart solar version are generally worth the price difference unless the budget is very tight. The £100 pound price I quoted is just a general guide for the price of the Smart Solar 75/10 . I would expect it can be found cheaper with some careful shopping.
If you do have an older “Blue solar” Victron controller there is an add on dongle availble from Victron that adds some (unfortunately not all ) of the features of the Smart solar models.
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+1 for the Smartsolar version, with app on tablet or phone. Can tell at a glance what's happening now as well as history and simple to adjust for different battery charging profiles. I've had a couple of cheap supposed MPPTs in the past with not good results.
 
syTaika said:
Personally I see it in a way that, the smaller the panel is, the more important it is to harvest everything possible out of it.
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I assume he's only using it to trickle charge the batteries while it's on the mooring, in which case it matters little. If he's trying to do more than that, then better to spend the money on some bigger panels first.
 
Lots to consider , am planning to carry temporary additional panels to plug in to bring it up to 100/150 watts but space is limited . Mainly would like to negate the losses of running the fridge etc in harbour when not connected to shore power .
 
Until it slipped and smashed the glass we had a rigid 60w suitcase folding solar panel. Actually 2 x 30w, which when you moved it a couple of times a day to face the sun really earned its keep.

It was replaced with one of these. The cloth case is less likely to scratch the wood work or GRP being deployed or put away and its very light. The quality is okay but not great, then again its only coming out when we are stationary. The solar controller is junk and was chucked out, couldn't even bring myself to sell it to a fellow yachtie. We run it through a small Victron Smart controller. If you are going to have your 60w of solar plus another 100w or so on occasional basis would be a good choice.

DOKIO 100W 12V Foldable Solar Panel Kit Monocrystalline with Solar Controller USB Output For Caravan RV Boat Camper Any Other Irregular Surface: Amazon.co.uk: Business, Industry & Science
 
dunkelly said:
Ok I was dumb enough to believe that e bay would not allow products to be missadvertised. I foolishly bought one of the cheap "mppt" controllers that keep draining the battery . But that is all in the past so the question is what size controller do I need for 3 X 20 watt solar panels and I would appreciate a recommendation as to a reasonably priced alternative , if there is one .! Many thanks
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I am a bit confused by OP claim that cheap controllers "that keep draining the battery." Yes the Chinese are great at misrepresenting controllers as MPPT. However the controller should still be OK as a PWM controller. ie it will allow solar charge in to the battery and reduce charge when battery is fully charged. In your case almost certainly continually charging with small panel wattage. The current drained (wasted) by the controller should be very near zero. Use a multimeter on ma scale to check with panels disconnected or covered. So I suggest that the controller you have may be OK. Batteries going flat for another reason. Yes true MPPT might get you 15% more charge but if you have room more panels will give you much more charge.
 
William_H said:
I am a bit confused by OP claim that cheap controllers "that keep draining the battery." Yes the Chinese are great at misrepresenting controllers as MPPT. However the controller should still be OK as a PWM controller. ie it will allow solar charge in to the battery and reduce charge when battery is fully charged. In your case almost certainly continually charging with small panel wattage. The current drained (wasted) by the controller should be very near zero. Use a multimeter on ma scale to check with panels disconnected or covered. So I suggest that the controller you have may be OK. Batteries going flat for another reason. Yes true MPPT might get you 15% more charge but if you have room more panels will give you much more charge.
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Perhaps the controller doesn’t contain blocking diodes.
 
Manosk said:
I have a victron 75 15 mppt to charge 2x100 amps batteries through 2x100w solar panels changed from a cheap chinese one
that only lasted 2 years of course lots of sunshine in Greece
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That's a bit close to the specification limit...200W at 12V is just over 16Amps, and your controller is rated at 15 Amps (although I guess you rarely get the full 200W evn in Greece)
 
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