240 watts of solar not managing fridge ?

[Ariadne]

Lots of people have a wrong idea of solar power. About half of the yachts I see have spoilers build at the back of the boat. Some even like the way that looks. Unfortunate they than also build a wind generator, a radar antenna en some other stuff on that same construction.
Those gizmo’s´s give shade ! So with the sun from the bow the mast is giving shade, with the sun from the side or behind those other toys create shadow. No charge!
Mooring in a marina or at a town quay, shadow all day from neighbour´s masts and rollergenuas. No charge.
September now, if the panels are not orientable to the sun, maybe half of the watts the manufacturer claims are generated. Days are getting short.
The cheapo Chinese panels are ok with full sun, a small cloud or hazy, the production of watts falls to ¼.
Measuring, best with an battery monitoring system. You will be surprised how little of your 240 watts comes in.
Stiill, there is something wrong with your system.

****!

I have 6 of the the Cheapo Chinese panels on my gantry/spoiler (for over 12 months, 7 of which relied solely on them as we had no alternator and were at anchor or sailing) and they work very well thank you very much. Been at anchor in the Carib' for the last 6 weeks and only needed 8 hours of engine hours to top up. Considering we have two kids on board who charge note pads, tablets, game boys etc, and we run a fridge that draws 6-7A almost continually as well as my and the wife's laptops, coffee grinders, blenders & 240v tools as well as everyday life sort of stuff they do alright. During daylight they put in between 25 & 30A.

I would guess the OPs problem is batteries and wiring, just get them checked out.

 

[GrahamM376]

Lots of people have a wrong idea of solar power. About half of the yachts I see have spoilers build at the back of the boat. Some even like the way that looks. Unfortunate they than also build a wind generator, a radar antenna en some other stuff on that same construction.
Those gizmo’s´s give shade ! So with the sun from the bow the mast is giving shade, with the sun from the side or behind those other toys create shadow. No charge!

Wrong. If one large panel then I may agree but, in our case we have 4 panels on the gantry which can be tilted fore and aft. Never have all of them in shadow from Aerogen. Can last indefinitely without running engine or genny in usual sunny weather, 2-3 days if overcast.

 

[pelissima]

I think this could last forever with no result.
It is because we are convinced your fridge consumption is wrong and also wiring is possibly erroneous. OldBawley suggested you use your multimeter to see actual Amps which I absolutely endorse. This will give us all hard facts. Then I would follow Chris Robb's advice about professional help at Vliho bay

 

[OldBawley]

Well, it took some time but the expected responses on my gantry-spoiler comment came in.
If people have solar panels up there and they ware smart enough not to build other shade giving gizmo’s´s over or around it, congratulations. Having them orientating gives 50 % more power in the lower latitudes. I learned it the hard way.
There are sailors with technical knowledge, and those without. The ones without have other skills, mostly in the financial sector, otherwise they would not cruise for long.
I am a dumba** in financial matters, so need to know how to help myself to keep the boat sailing and have a cruising life without financial problems.
In two cases I convinced sailor- cruisers with big wallets but no tech knowledge that their beautiful build power tower at the back of the boat was of little use simply by measuring. Measuring is knowing. Both took away the wind generator after I pressed there nose on the multimeter. Here in the Med a wind generator is of very little use in the summer months. In summer, days are long and the sky is blue, even badly placed or connected solarpannels generate masses of power, however, if shaded by a windgen or a radar doom nothing.
Winter and especially autumn is a challenge trying to keep up with electrical energy without using diesel. I like to do all boat moving by sail, our diesel is only used if there is no other way. So all power has to come from the solarpannels and wind generators.
Indeed, two wind generators. On top of the yawl mast stands a Aerogen and if necessary I mount a self build six feet dia wind generator on the port side just in front of the stays. Takes 15 minutes to rig the big beast, I have to admit it looks weird but where I anchor in winter is nobody to complain.

 

[Chris_Robb]

I think this could last forever with no result.
It is because we are convinced your fridge consumption is wrong and also wiring is possibly erroneous. OldBawley suggested you use your multimeter to see actual Amps which I absolutely endorse. This will give us all hard facts. Then I would follow Chris Robb's advice about professional help at Vliho bay

Agreed - also the insulation on those fridges is not brilliant and they are front opening which means they lose all their cold air every time the door is opened.

Batteries are obviously now useless, if they have been at 11V most days.

So the problem of amps being consumed needs to be solved. No amount of new batteries and panels is going to deal with the amps taken by an inefficient fridge. You really need to see how you can insulate the fridge more and solve your amps consumption.

That is the task in hand - then sort the batteries out. If you do a good enough job then the words deep cycle will be irrelevant and you will never cycle the batteries to more than 70% of full.

 

[AndrewB]

Several people have suggested wiring problems. I had a long-term problem with my fridge due to this, and like the OP, found a new solar panel only gave limited success. Each time it kicked in, there was an instantaneous high draw, and I discovered the voltage at the fridge momentarily dropped from 12.6v to about 10.5v, below the cut-out voltage, so it would cut out again. It would then cycle over and over. The fridge would run normally only when the batteries were being charged above 13v. Heavier duty wiring to the fridge solved this problem.

Incidentally the many refridgeration guys we consulted about this were completely useless. Their sole maintenance skill is to refill with gas - whether you need it or not - and charge an outrageous fee. Another yachtie, more competent than me, diagnosed the problem.

 

[Pete7]

I may have read this wrong but how do you run 2 x 80w panels and 2 x 40w panels through a Solar 135? The maximum wattage of the Solar 135 is 135w. We have two of them connecting two panels to the house bank because it was just simplier to wire that way, and they work very well.

I wonder if you have damaged the regulator or it is in some way self limiting to 135 watts regardless of the power you feed into it.

Pete

 

[ccscott49]

I have 4 80w solar panels, which live on the wheelhouse roof, however they are on long leads, I move them around, lean them up against the main boom, to show the correct aspect to the sun, makes a huge difference in output.
I also have a fridge in the bridge, which at certain times of the day, the sun shines on the door, just hanging a towel in front of the door, with an air gap behind, makes a huge difference to fridge consumption. That as well as LED lights throughout has helped my not un substantial power consumption. I try to restrict my genny usage.
To get back to the OP, I think your batteries are stuffed, with what has been said.

 

[grafozz]

buzzer !

I may have read this wrong but how do you run 2 x 80w panels and 2 x 40w panels through a Solar 135? The maximum wattage of the Solar 135 is 135w. We have two of them connecting two panels to the house bank because it was just simplier to wire that way, and they work very well.

I wonder if you have damaged the regulator or it is in some way self limiting to 135 watts regardless of the power you feed into it.

Pete

there are 2 x regulators on board , 80w + 40w on each , and they seem to work fine .
last night the buzzer started going off and the fridge had to be turned off so we could sleep on !

 

[Chris_Robb]

there are 2 x regulators on board , 80w + 40w on each , and they seem to work fine .
last night the buzzer started going off and the fridge had to be turned off so we could sleep on !

I was advised when I fitted mine (2 x 85 watts) to get a regulator capacity that was double the actual requirement.