Would some one kindly advice, I am just exsperimenting at the moment. : )

Good evening from a sunny Mullion Cove Cornwall

Would some one kindly advice, I am just experimenting at the moment.

I have been given a 72 cell 24 volt solar panel.

It produces the correct current into an AVO 8 as per the label on the back 5 plus amps

The box full of 24 volt invertors I was given with it have very corroded outer cases, and are for mains connection, so despite replacing faulty components they produce no output as I am not feeding to mains.

I have an old 250 watt inverter we used to use with the caravan, and the lead acid battery just replaced in the car.

The battery hold a reasonable charge, enough I think for testing, but was becoming a problem to start the car if it was not use for a couple of weeks.

OK the charge controller at the link looks as is it would do for a start, until I have more panels and battery's and know more of what I am doing : ).

Possible charge controller

The battery I have is 12 volt 75 amp hours.

The panel 24 volt

The invertor 250 watt

This company offer from 10 amp to 100 is this related to the battery ?

I thought of going for the 100 option.

Will it do the job and feed the inverter I have as a load ?

Thank you for your time God Bless Chadd

For just playing around I would buy the 10a it is good for the one panel you have. Just connect the battery to it first. When you know more of what you're doing buy a good name brand charge controller.

Good luck

Chadd said:

Good evening from a sunny Mullion Cove Cornwall

Would some one kindly advice, I am just experimenting at the moment.

I have been given a 72 cell 24 volt solar panel.

It produces the correct current into an AVO 8 as per the label on the back 5 plus amps

The box full of 24 volt invertors I was given with it have very corroded outer cases, and are for mains connection, so despite replacing faulty components they produce no output as I am not feeding to mains.

I have an old 250 watt inverter we used to use with the caravan, and the lead acid battery just replaced in the car.

The battery hold a reasonable charge, enough I think for testing, but was becoming a problem to start the car if it was not use for a couple of weeks.

OK the charge controller at the link looks as is it would do for a start, until I have more panels and battery's and know more of what I am doing : ).

Possible charge controller

The battery I have is 12 volt 75 amp hours.

The panel 24 volt

The invertor 250 watt

This company offer from 10 amp to 100 is this related to the battery ?

I thought of going for the 100 option.

Will it do the job and feed the inverter I have as a load ?

Thank you for your time God Bless Chadd

Click to expand...

Experimenting but what do you want to achieve? If you have spare money to buy things and to put them in a big bucket later to never be used again then go ahead and buy the 10A controller. If however you wish to look at running some appliances for your caravan then that is another matter.

So the question is what do you want to run and what is the wattage

Do NOT buy that controller!!! They are lieing! That is a fake MPPT, which is very common on internet sale sites. It is really just a cheapo PMW controller with an MPPT label slapped on it.

At best, if you connect that controller to your battery, the battery will get some charge, but will be limited to the raw amps coming out of the panel. Here's what happens. That 72 cell panel is likely to be putting out ~8A at 37.5V. 300W. If that controller is connected to the battery, the battery will drag the panel voltage down to battery voltage, or somewhere around 12.5V. So, 8A at 12.5V will go into the battery. If instead you bought a real MPPT controller, that 8A at 37.5V would be transformed to 24A at 12.5V. So, the fake controller wastes about 3/4 of the potential charging.

Good afternoon Tim,

Thank you for your reply.

It is not for a caravan that is long gone.

I have heard from local people that the payback on installations that feed the grid, was exaggerated by the sellers.

This does not at all surprise me given the way the world is, I trust my own judgement plus that of enthusiasts like yourselves.

Others have had a high failure on inverters due to them being mounted outside in the sea air.

All I want to do at the moment is hook up what I have and see if it is of any use to power a few LED lights in the house.

We rent the gift shop out which we live above, that is fed via a coin meter from the flat supply.

We charge our tenants at the rate we pay for units, we pay the standing charges to help the tenants.

If in the future I could generate the power they use for the shop as well as some for us, I could have an income from it, perhaps ?

The shop has LED lighting.

There is no set plan at the moment, I only wish to just play with what I have outlaying as little as possible in case we do not proceed further.

Our roof faces south Cornwall has a lot of sun electricity is going up and up.

So for now the charging unit online was not expensive everything else was free.

I feel I shall if required be able to obtain other used panels at low cost and build from there.

One question that was not an answered was the different size's available for the regulator offered in the eBay listing, 10, 50 up to 100 amps, they were all similar prices so why not go for the 100 amp one to cover more panels in the future ?

God Bless Chadd

MichaelK said:

Do NOT buy that controller!!! They are lieing! That is a fake MPPT, which is very common on internet sale sites. It is really just a cheapo PMW controller with an MPPT label slapped on it.

At best, if you connect that controller to your battery, the battery will get some charge, but will be limited to the raw amps coming out of the panel. Here's what happens. That 72 cell panel is likely to be putting out ~8A at 37.5V. 300W. If that controller is connected to the battery, the battery will drag the panel voltage down to battery voltage, or somewhere around 12.5V. So, 8A at 12.5V will go into the battery. If instead you bought a real MPPT controller, that 8A at 37.5V would be transformed to 24A at 12.5V. So, the fake controller wastes about 3/4 of the potential charging.

Click to expand...

Thank you for your reply, I understand more how it works each day : )

I have been in alectronics since 1961 but this is new to me : )

The question remains how to tell if the seller is untruthful ? it did not make a lot of sense buying an expensive one to start with, in case I do not get any further.

Do you have any recommendations ?

Thank you for your time Chadd

Sadly, it is getting harder and harder. Usually, one can tell by looking at the voltage limits. If it mentions a max voltage of something low like 36, or 48V, then it is fake. Another clue that "rednecktech" brought up recently is the presence of USB ports. There appear to be no "real MPPT" controllers with USB ports. The give-a-way that I have alwaysed used is shipping weight. A real MPPT weights a lot more because of the big toroid rings of thick copper needed to transform the voltage. So, if a controller shipping weight is 6oz, it is fake. If it is 6lbs, it is real.

What to select now depends on the amps passing through the controller, and how much you think of individual brands. Let's use the example from your panel above. Assuming your 72cell panel is 300W and it is putting out 8A at 37.5V, when the controller transforms it, it will be putting out 300W/12.5Acharging = 24A. Assuming your panel is never puts out more than 85% of rating, that works out to be 24A X 85% = 20.4A.

So, get a real MPPT that can handle 20+Amps of current. You might want to look at Epever. Their 4210AN might be a good choice. At 40A it will easily handle that 300W panel, and if you want expansion in the future, it can handle the expansion too.

Yes, the Epever will be much more than the 10£ that cheap controller costs, but you get what you pay for.

X2 for Epever.

Michael has given you some good advice.

MichaelK said:

Sadly, it is getting harder and harder. Usually, one can tell by looking at the voltage limits. If it mentions a max voltage of something low like 36, or 48V, then it is fake. Another clue that "rednecktech" brought up recently is the presence of USB ports. There appear to be no "real MPPT" controllers with USB ports. The give-a-way that I have alwaysed used is shipping weight. A real MPPT weights a lot more because of the big toroid rings of thick copper needed to transform the voltage. So, if a controller shipping weight is 6oz, it is fake. If it is 6lbs, it is real.

What to select now depends on the amps passing through the controller, and how much you think of individual brands. Let's use the example from your panel above. Assuming your 72cell panel is 300W and it is putting out 8A at 37.5V, when the controller transforms it, it will be putting out 300W/12.5Acharging = 24A. Assuming your panel is never puts out more than 85% of rating, that works out to be 24A X 85% = 20.4A.

So, get a real MPPT that can handle 20+Amps of current. You might want to look at Epever. Their 4210AN might be a good choice. At 40A it will easily handle that 300W panel, and if you want expansion in the future, it can handle the expansion too.

Yes, the Epever will be much more than the 10£ that cheap controller costs, but you get what you pay for.

Click to expand...

Thank you for the warning I will look up the model you mention. : )
I just read the smaller print on one advertised on Amazon which could have other wise caught out the unwary.
God Bless Chadd

Amazon

Q:My solar panel is 36V 200W,can I charge 12V battery? A:To charge a 12V battery,the working voltage of the solar panel can be between 17V and 23V(Voc),and for a 24V battery,the working voltage of the solar panel can be between 36V and 46V.(Voc) Please make sure that the working voltage of the power supply and solar panels are within this range. If it is too high, the controller will be damaged.

Hi Chadd, I’m originally from Newport SW but live in Australia and currently in Mykonos on route to the UK in 2 weeks. Happy to help out but responses may take some time….will post a reply later this evening for you.

Hi again Chadd. That reply from the Amazon seller is so wrong.

I have found a EPEver seller and no EBay is not always there cheapest option.

30A Epever Triron

The seller has a physical address and phone number and if you read the description you will find it is meets all the parameters.

Ignore what salesmen are telling you about solar production because you can do your own calculations based on the size of the system you are proposing. Look in the resource section for a calculator.

Good afternoon Tim from a sunny Mullion Cove Cornwall, mind you it appears to be sunny all over at the moment, nice breeze here though which is good : )

We see you are much travelled.

Thank you for the link.

I have ordered a very low cost one on eBay that according to its description, should enable the 24 volt panel to keep its volts up, while charging a 12 volt battery and transfer maximum current to the battery.

I now know from previous posts on how to check and what it should do : )

I mentioned this in a note with payment, so if the unit does perform as described, it will be (not as described) and returned at the sellers cost for a full refund.

Once the idea is proven, more panels and upgraded equipment will follow.

We would willingly spend out on a system but this world is full of dishonest salesmen, who in the end cut their own throats, so its DIY and research with everything we do.

I am used to dealing with both sales and purchases on eBay and have never come unstuck, yet : )

We want an independent supply, as there are a lot of power outages in this part of Cornwall due to overhead wiring and high winds in the winter months.

The cost of power is the main reason though, I would love to tell them what to do with their supply LOL

God Bless Chadd

Tim Tim said:

Hi again Chadd. That reply from the Amazon seller is so wrong.

I have found a EPEver seller and no EBay is not always there cheapest option.

30A Epever Triron

The seller has a physical address and phone number and if you read the description you will find it is meets all the parameters.

Ignore what salesmen are telling you about solar production because you can do your own calculations based on the size of the system you are proposing.

Click to expand...

Tim Tim said:

Look in the resource section for a calculator.

Click to expand...

Good evening Tim,

It says ( Works with Gel, Sealed, Flooded & Lithium batteries )

I read that should include lead acid as in car battery ?

There are a lot of different models online of that brand, but that is a good price as far as I can tell.

I beleive there are also models with PC or phone connection.

The different model numbers are some what confusing to compare like for like.

I am happier buying from eBay, as there is the third party eBay to call on if there are problems.

I have just returned a cheap one, it was not MPPT as listed pulling the 70 cell panel down to 13 volts.

The parameter menu did not select and it started shutting down after a while, so totally useless.

Thank you all for the previous advice, I had to try a cheap one to prove to myself that sellers either try it on, or have no knowlege of the products they are selling : )

I think I shall go for the one at the link you provided : )

God Bless

Chadd said:

Good evening Tim,

It says ( Works with Gel, Sealed, Flooded & Lithium batteries )

I read that should include lead acid as in car battery ?

There are a lot of different models online of that brand, but that is a good price as far as I can tell.

I beleive there are also models with PC or phone connection.

The different model numbers are some what confusing to compare like for like.

I am happier buying from eBay, as there is the third party eBay to call on if there are problems.

I have just returned a cheap one, it was not MPPT as listed pulling the 70 cell panel down to 13 volts.

The parameter menu did not select and it started shutting down after a while, so totally useless.

Thank you all for the previous advice, I had to try a cheap one to prove to myself that sellers either try it on, or have no knowlege of the products they are selling : )

I think I shall go for the one at the link you provided : )

God Bless

Click to expand...

Hi Chad yes you are correct a flooded battery includes a lead acid car battery. You can buy a Bluetooth module to connect to your phone for the one on the link I provided if you want to play around but be aware that it disconnects when out of range. Unless you have the controller hidden away somewhere then there is no benefit in having remote access.

'Playing' with solar, panel , controller, battery and a few led lights is one thing, a hobby for interest. Connecting to a dwelling where you have a paying tennent is quite different. You are required to have professional instalation, commissioning and testing for any electrical system.
Even a 12v car battery incorrectly wired up can burn the house down.

Mike

mikefitz said:

'Playing' with solar, panel , controller, battery and a few led lights is one thing, a hobby for interest. Connecting to a dwelling where you have a paying tennent is quite different. You are required to have professional instalation, commissioning and testing for any electrical system.
Even a 12v car battery incorrectly wired up can burn the house down.

Mike

Click to expand...

Good evening Mike,

Thank you for your concern, I shall abide by the rules.

I do realise that there are regulations and the high current from a car battery can melt wires and cause fires.

My vintage radio workshop has high current supply's for rotary generators, lots of fuses and great care in the wireing : )

I have also had experience of incompetent roofers, seen the flooding from plumbers and heard from locals whose homes were built by useless builders : )

We have had two roofers to court and ended up re-slating and laying two rubber roofs ourselves in our 70s.

We did our research and found the correct advice and products : ).

I have been in electronics since 1961, radio and TV also radio telephone installations both base and mobile 12 - 24 volt in ships as well as road vehicles.

If I have to have a system installed, first I want to know all about it and calling on the experience of you learned gentlemen is a very good start. : )

Next I play with a small installation set up by myself, this will stop me being fed rubbish by tradesmen only interested in money.

A local fisherman Barry has mains fitted roof panels, they do not return anything like the power he was given to believe.

The panel I have was one or many on a bungalow on the cliff, the alloy cases of the invertors have been eaten away by the sea air, splitting them open most had failed.

A thoughtless installation.

I noticed the firm that sells those controllers also has small wind generators, interesting.

We get lots of wind, maybe a mix of the two ?

God Bless Chadd : )

The deed is done, I have just ordered online using PayPal which gives us some protection : )

Good afternoon Gentlemen,

The unit has arrived on time.

I shall also of course contact the seller with this question. : )

The model is EPEVER TRIRON3210N.

There is a small plug in sensor RT-MF58R47KE. 81A and a corresponding socket on the unit bottom left.

The instructions say connect one end of the remote temperature sensor to the controller, the other end close to the battery, or the unit will default to 25c charging discharging.

There is however no cable supplied just the sensor ?

Does anyone know if this cable is an extra ?

Should I plug the sensor directly into the charge controller for now or leave it out ?

Thank you Chadd

Chadd said:

Good afternoon Gentlemen,

The unit has arrived on time.

I shall also of course contact the seller with this question. : )

The model is EPEVER TRIRON3210N.

There is a small plug in sensor RT-MF58R47KE. 81A and a corresponding socket on the unit bottom left.

The instructions say connect one end of the remote temperature sensor to the controller, the other end close to the battery, or the unit will default to 25c charging discharging.

There is however no cable supplied just the sensor ?

Does anyone know if this cable is an extra ?

Should I plug the sensor directly into the charge controller for now or leave it out ?

Thank you Chadd

Click to expand...

Even though it has been hot there you won’t need it….It hasn’t been that hot .

You just plug the sensor in as your controller will be close to the battery and all you are doing is measuring the air temperature.
You will not need the cable type which is for a remote sensor and is an optional extra.

Remember to connect to your battery first and then to your solar panels.

In Athens at the moment and UK on Saturday. Will heading down to near Plymouth next week.

Thank you Tim all understood, Athens anything Greek sounds nice, I can almost taste the musaka : )

I met a guy today at the local boot sale who sells Lithium batteries online

Batteries

I have not visited his site yet, or any others regarding batteries, the one he had with him was 200 amp and had Bluetooth.

Not as heavy as lead acid.

Also been looking at the various methods used to secure panels to a slate roof.

if we do eventually have to have others do the installing, I want to be in control of what they get up to : )

I should much prefer to install ourselves and have it approved if that is possible.

God Bless Chadd

,

Hi Chadd, I just had a look at his web site and it sends out big warnings to me. I wont go into detail just yet but what is a guy doing selling batteries in a car boot sale 18 miles from his so called warehouse. He claims to have been off grid for 20 years and bringing the price down on batteries for the last 5.

I love this claim,

‘So over the last 5 years we have be solely responsible for bringing the cost down to end user by avoiding expensive google ad campaigns, ebay fees and third party handling charges.

With the help of our manufacturing team we put together quality EVE cells, and a trusted programmable BMS by JBD, and a quality build.‘

They don't manufacture as the Archibald batteries can be bought on Alibaba and the ones with his so called company name on are just a printed name on the case which he can also get done in China.

Archibald Batteries

Will post more tomorrow.

Thank you Tim for taking the trouble to look : )

He was not selling them at the car boot as far as I know ? there was on one the ground and a 1000w inverter, which he may have been using to offer to test items for sale, I am not sure on that point.

The gentleman and his lady had purchased the collection of a deceased audio file.

It was way into the boot sale which covers the whole of a football pitch, by the time we reached him there was just box's of cables.
I purchased a nice multi speaker switching box, the conversation drifted to old radios, then I mentioned what I was up to at this time with solar panels.

The other points you mention though are good to know, people do claim to be a lot more that they are : )
The gents website was to be a starting point, as I have only an old 70 amp well use car battery at the moment, the replacement OEM one I purchased on Ebay was £57 delivered, also 75 amp hour.

I know very little about lithium battery's yet or invertors, but the world of knowledge is out there.
God Bless Chadd