[P @ F]

Well sods law has worked its magic , following my little solar experiment my battery has decided to give up the ghost , not i think through the trials but just bad luck .

I have only just upgraded the system to 120 watt of solar from 80 watt to compensate for winter , the cheap £50 , 85 amp leisure battery tells me on all devices i have that it is fully charged , 3 watt meters , 2 smart chargers , 1 multimetre , 1 flow controller all give me readings of over 13 volt after battery rested for at least 4 hours
No sooner do i fire up the pumps and it drops to 12.2 volt which is 25% charged , due to the 120 watts of solar through an MPPT controller and its ability to  give me  6 amps on tap in bright conditions i am able to carry on , but i think i could come a cropper on a poor day .
I know the answer is simply to get a new battery but am in a bit of a tiz over what to choose ?

85 amp will do the job fine i think , with what i can put in against what i take out i should be always in either absorbtion or float mode which is as near to fully charged as you can get , which should keep the battery in top condition .

115 amp  will in effect be a bigger fuel tank for me , but if solar yield is not so good i could find myself hovering in the 50/75% charge area , not so good for the battery in terms of maintaining a healthy battery .

Or i am looking at the possibility of a car battery , many people have good results from them , due to the lower amp capacity of them i should also mostly be in float mode , the question is can they handle say 6 amps going in for short bursts , i am not aware of what a car alternator pumps in on average , or more to the point , as the lead plates are thinner will i cook the thing ?
My MPPT controller will stop any danger of overcharge i think , but i am just interested as to what you guys think ?

Rich 
 

[CleanClear]

Just a mad question seeing as you have an MPPT controller............
 I know how it is supposed to be wired as it clearly tells you, but what happens if you put your "load" to your battery(as well)  ? Yes i already know its charging it, but if you run seperate load wires to your battery ? Would it still charge and fund the extra power draw if that makes sense ?

[P @ F]

    , No not mad at all , i never thought of that !
I suppose it would just cut down what went to battery  by whatever it sensed as the load , after all it can only process what is coming in via the panel .
Do forgive me if i dont try it out though , £80 for a new MPPT would be a costly firework display 

[Spruce]

Well sods law has worked its magic , following my little solar experiment my battery has decided to give up the ghost , not i think through the trials but just bad luck .

I have only just upgraded the system to 120 watt of solar from 80 watt to compensate for winter , the cheap £50 , 85 amp leisure battery tells me on all devices i have that it is fully charged , 3 watt meters , 2 smart chargers , 1 multimetre , 1 flow controller all give me readings of over 13 volt after battery rested for at least 4 hours
No sooner do i fire up the pumps and it drops to 12.2 volt which is 25% charged , due to the 120 watts of solar through an MPPT controller and its ability to  give me  6 amps on tap in bright conditions i am able to carry on , but i think i could come a cropper on a poor day .
I know the answer is simply to get a new battery but am in a bit of a tiz over what to choose ?

85 amp will do the job fine i think , with what i can put in against what i take out i should be always in either absorbtion or float mode which is as near to fully charged as you can get , which should keep the battery in top condition .

115 amp  will in effect be a bigger fuel tank for me , but if solar yield is not so good i could find myself hovering in the 50/75% charge area , not so good for the battery in terms of maintaining a healthy battery .

Or i am looking at the possibility of a car battery , many people have good results from them , due to the lower amp capacity of them i should also mostly be in float mode , the question is can they handle say 6 amps going in for short bursts , i am not aware of what a car alternator pumps in on average , or more to the point , as the lead plates are thinner will i cook the thing ?
My MPPT controller will stop any danger of overcharge i think , but i am just interested as to what you guys think ?

Rich

Rich,
You are panicking when you don't really need to atm.

Your battery will drop voltage after you have had the pump working. If you switch your solar array off, you will find that the battery voltage will slowly creep back up from 12.2 volts to 12.6/7v depending on how much you have worked the battery and how much you have taken out. (So if your pump is run for an hour and has drawn 5 amps, then after a 4 hour rest your volt meter will be showing a virtually fully charged battery.)

As the capacity in the battery is used up the voltage will drop into the 11 volts area under load. You are in trouble when your battery voltage under load drops to 10.4 volts.  That's flat. To save the battery your controller will automatically cut out provided you haven't activated the overide (this only applies to the latest Spring controllers).

We have just replaced an old 5 year old Numax battery with another Numax (85 amph) about 6 months ago. The latest Numax batteries are leaning toward the new Calcium technology and they are now quoting a CCA value. CCA means Cold Cranking Amps so these are now dual purpose batteries which are both leisure and starter batteries - like the Trojan traction batteries.

Your MPPT controller is programmed to boost charge your batteries at 14 volts regularily.  I honestly would like to see it slightly higher (14.2 - 14.5 v) as that stirs up the chemical action inside the battery a little more. But the suppliers are really playing safe with this so they are guaranteed that the battery won't give of poisonous gasses at this charging voltage.

.

[Spruce]

Just a mad question seeing as you have an MPPT controller............
 I know how it is supposed to be wired as it clearly tells you, but what happens if you put your "load" to your battery(as well)  ? Yes i already know its charging it, but if you run seperate load wires to your battery ? Would it still charge and fund the extra power draw if that makes sense ?

The inside of the battery has electrical resistance. The panels will only provide the maximum amount of charge that they can and the battery will only accept what it can. As the state of battery charge gets fuller the resistance increases.

With the battery being connected up the correct way to the MPPT controller, all the available amps collected by the panels will be being sent to the battery. If the battery won't accept that rate of charge (its nearly fully charged for example) then the extra power not used is shed. So if a battery will only accept a charge of 1 amp then connecting an extra lead to the load isn't going to push any more current into the battery.

The load connection is usually not battery related. It doesn't 'regulate' (bulk, absorbtion, float,) the current like the battery side of the controller does. This is where you connect a 230v inverter to. If you are using an electrical tool which consumes more than the panels are providing, the 'load' will take everything from the panel and draw the shortfall from the battery. The load takes preference.

So P&F could wire his pump into the load rather than directly from the leisure battery terminals. The controller will draw all the current it can from the panels and any extra from the battery. When he stops to talk to a customer, the MPPT controller directs the power generated back into the battery trying to replace what it took earlier.

ATM Rich's panels are supplying 6amps. His pump will be drawing a max of 5 amps. So he has an extra 1amp being put back into the battery when he is cleaning windows. That's great. His battery will be virtually fully charged and the controller will be on float mode.
 But in the summer he may have to 'design'/make a cover to fit over one of the panels to reduce output.

.

[P @ F]

Just a mad question seeing as you have an MPPT controller............
 I know how it is supposed to be wired as it clearly tells you, but what happens if you put your "load" to your battery(as well)  ? Yes i already know its charging it, but if you run seperate load wires to your battery ? Would it still charge and fund the extra power draw if that makes sense ?

The inside of the battery has electrical resistance. The panels will only provide the maximum amount of charge that they can and the battery will only accept what it can. As the state of battery charge gets fuller the resistance increases.

With the battery being connected up the correct way to the MPPT controller, all the available amps collected by the panels will be being sent to the battery. If the battery won't accept that rate of charge (its nearly fully charged for example) then the extra power not used is shed. So if a battery will only accept a charge of 1 amp then connecting an extra lead to the load isn't going to push any more current into the battery.

The load connection is usually not battery related. It doesn't 'regulate' (bulk, absorbtion, float,) the current like the battery side of the controller does. This is where you connect a 230v inverter to. If you are using an electrical tool which consumes more than the panels are providing, the 'load' will take everything from the panel and draw the shortfall from the battery. The load takes preference.

So P&F could wire his pump into the load rather than directly from the leisure battery terminals. The controller will draw all the current it can from the panels and any extra from the battery. When he stops to talk to a customer, the MPPT controller directs the power generated back into the battery trying to replace what it took earlier.

.

Hi Spruce  , this is the question i asked at the place i bought the MPPT , why do i not use the load for my application , they just said its better to go from pump to battery not load , due to the amp pull , they said it would be the same if you were to use an inverter , it has also been seen by myself on NoClueTube 

Im just doing what im told , but going back to my voltage drop , on Sunday i fully charged the battery and let it rest , then i ran the pump without a solar feed , it took about 1 hour to get from 13.6 to having Bat displayed on flow controller meaning i think that it was just about to shut itself off ?
Also today i could actually see a marked increase in flow when the sun popped its head from the clouds 

But what do you think of my battery options anyway ? , which way would you go ?

[Spruce]

I would connect your load directly to the battery.  You will arrive at the same 'destination'; is just you have taken a different route. Your battery is still going to receive 1 amp no matter which way you connect it up.

You are going to see an increase in power with the pump as you are pushing it with a higher voltage. My fan on my diesel heater air heater runs slower as I switch the engine off. The voltage to the heater drops as its now being driven by 12volts rather than 14.2 volts when the engine was running. The alternator is suppling the fan with 16% higher voltage.

If your battery voltage is dropping that fast, then its time for a new battery. I would replace it with a leisure battery tbh rather than a starter battery. As I've said, Numax has done us well over the years wfp.

.

[P @ F]

I would connect your load directly to the battery.  You will arrive at the same 'destination'; is just you have taken a different route. Your battery is still going to receive 1 amp no matter which way you connect it up.

You are going to see an increase in power with the pump as you are pushing it with a higher voltage. My fan on my diesel heater air heater runs slower as I switch the engine off. The voltage to the heater drops as its now being driven by 12volts rather than 14.2 volts when the engine was running. The alternator is suppling the fan with 16% higher voltage.

If your battery voltage is dropping that fast, then its time for a new battery. I would replace it with a leisure battery tbh rather than a starter battery. As I've said, Numax has done us well over the years wfp.

.

You confused me a bit here , when you say load direct to battery , do you mean pump straight to battery or to run an extra wire from load on solar controller to the battery ?

Ok , leisure it is , but 85 or 115 ?

[P @ F]

As it is  at the moment i have the WFP set up the conventional way , the battery output from solar controller goes to the battery and the load output from the solar controller is not used .
Is this what you mean ?

[Spruce]

As it is  at the moment i have the WFP set up the conventional way , the battery output from solar controller goes to the battery and the load output from the solar controller is not used .
Is this what you mean ?

Yes,
So the MPPT controller will only have 2 feeds, the cables from the solar panels and the cables from the controller to the battery.

Battery. If you have space its always better to go higher. But if you have to carry the battery any distance in winter to bench charge it, then its pretty heavy.
Depending on how your panels perform in the winter it may mean you only have to bench charge a bigger battery every 4 days rather than every 3 days with a smaller battery, for example.

As a single operator the 85 amp batteries have been fine for us. ATM having a bigger battery will just mean that you have a bigger reserve. If you are still using less current than the solar is putting in then its a matter of time before the extra current will completely fully charge your battery no matter how big it is.

[Spruce]

Just a mad question seeing as you have an MPPT controller............
 I know how it is supposed to be wired as it clearly tells you, but what happens if you put your "load" to your battery(as well)  ? Yes i already know its charging it, but if you run seperate load wires to your battery ? Would it still charge and fund the extra power draw if that makes sense ?

The inside of the battery has electrical resistance. The panels will only provide the maximum amount of charge that they can and the battery will only accept what it can. As the state of battery charge gets fuller the resistance increases.

With the battery being connected up the correct way to the MPPT controller, all the available amps collected by the panels will be being sent to the battery. If the battery won't accept that rate of charge (its nearly fully charged for example) then the extra power not used is shed. So if a battery will only accept a charge of 1 amp then connecting an extra lead to the load isn't going to push any more current into the battery.

The load connection is usually not battery related. It doesn't 'regulate' (bulk, absorbtion, float,) the current like the battery side of the controller does. This is where you connect a 230v inverter to. If you are using an electrical tool which consumes more than the panels are providing, the 'load' will take everything from the panel and draw the shortfall from the battery. The load takes preference.

So P&F could wire his pump into the load rather than directly from the leisure battery terminals. The controller will draw all the current it can from the panels and any extra from the battery. When he stops to talk to a customer, the MPPT controller directs the power generated back into the battery trying to replace what it took earlier.

.

Hi Spruce  , this is the question i asked at the place i bought the MPPT , why do i not use the load for my application , they just said its better to go from pump to battery not load , due to the amp pull , they said it would be the same if you were to use an inverter , it has also been seen by myself on NoClueTube 

Im just doing what im told , but going back to my voltage drop , on Sunday i fully charged the battery and let it rest , then i ran the pump without a solar feed , it took about 1 hour to get from 13.6 to having Bat displayed on flow controller meaning i think that it was just about to shut itself off ?
Also today i could actually see a marked increase in flow when the sun popped its head from the clouds 

But what do you think of my battery options anyway ? , which way would you go ?

They give advise that would cover themselves as they have no idea what people are going to do with their products. I'm sure there will be someone out there that will connect a 3000 watt inverter onto the load connections without any thought or understanding of its implications. When the controller 'blows up' they will be the first to shout about a poor quality product.

By connecting the inverter directly to the battery will mean the damage will be done to the battery and not the controller. So as a technical advisor for Victron, the advise to connect all load to the battery is good.

.

[P @ F]

OK then , I am wired correctly , so the only thing to do now is to make the choice on amp size .
I have decided to go for a better quality 85 amp than i usually get , my reasoning is that there is far more chance of being able to keep it fully charged , more so during winter when solar is not so abundant , as you know my drive behind the whole solar bit was to not have to remove the battery at all , i feel this is my best chance .

Two other things that i see as an issue are smart chargers and sulphation , as smart as these chargers are i do believe that low range models are the route cause of a lot of battery failures , ok fine , you plug and go and you cannot cook the battery to an early demise (as i have in the past with dumb chargers ) , but this is what helps sulphation get a grip unless the smart charger has a sulphation step built in , neither of mine do as they are 40 quidders .

As sulphation can only be stopped at the higher voltages than a cheap smart charger will  provide i think that a little delve into what voltage is used to de sulphate and for how long it is applied , if i manage to keep the battery fully charged then its all good , if not then i have a plan to bypass the solar controller now and then and feed the higher voltage direct for the given time .
This could be the reason that Nathankaye has not managed to kill his battery off by not using a solar controller and keeping an eye on his battery voltage .

[Spruce]

OK then , I am wired correctly , so the only thing to do now is to make the choice on amp size .
I have decided to go for a better quality 85 amp than i usually get , my reasoning is that there is far more chance of being able to keep it fully charged , more so during winter when solar is not so abundant , as you know my drive behind the whole solar bit was to not have to remove the battery at all , i feel this is my best chance .

Two other things that i see as an issue are smart chargers and sulphation , as smart as these chargers are i do believe that low range models are the route cause of a lot of battery failures , ok fine , you plug and go and you cannot cook the battery to an early demise (as i have in the past with dumb chargers ) , but this is what helps sulphation get a grip unless the smart charger has a sulphation step built in , neither of mine do as they are 40 quidders .

As sulphation can only be stopped at the higher voltages than a cheap smart charger will  provide i think that a little delve into what voltage is used to de sulphate and for how long it is applied , if i manage to keep the battery fully charged then its all good , if not then i have a plan to bypass the solar controller now and then and feed the higher voltage direct for the given time .
This could be the reason that Nathankaye has not managed to kill his battery off by not using a solar controller and keeping an eye on his battery voltage .

The issue regarding intelligent chargers is safety - allegedly and effects the charging industry as a whole. (CTEK say they have a battery reconditioning cycle but they don't say much in their literature. Most of the hype comes from the sales side of the industry.)

Leisure batteries centered around caravans and caravans store their batteries in the living compartment, usually in a locker or under a bunk. So the decision was to hold the charging at 13.9 to 14.0v. That way they are guaranteed there will be no gassing and so no harmful substances released into the living space.  An intelligent charger doesn't need to completely fully charge the battery with a higher voltage as the leisure battery will get that when the caravan is towed to site/home.
Most leisure batteries are also sealed (maintenance free) so they definitely don't want that to gas.  My current leisure battery is an Oldham and that has screw caps for topping up water. There is also a gas release tube that is feed through a hole in the floor so it vents outside. (The battery is 3 years old in January and I have never needed to top it up with water. Even with 14.5 volts going into it there is absolutely no bubbling. So this is safety issue is nonsense.) 

Canal boats are in the same situation. If based in a Marina mooring, a 230v power supply is usually provided which, like a caravan has on onboard battery charger. But each time the narrow boat engine is run the leisure batteries will be getting a higher voltage charge.

Its not too difficult to add a standard 12v (say 40 amp) headlight relay. What you are doing is running a lead that will take 25 amps from the postive terminal on your starter battery to the positive terminal on the leisure battery.  You need the relay to the circuit so your batteries remain seperated when the engine isn't running. The relay has 4 terminals. Two of them are the main current in and out and the other 2 are the coil. When a current is feed through the coil a magnetic field is created which pulls the contacts together and joins the batteries together.
You just need to look for a cable in the fuse box that is on when the ignition is on and is off when the ignition key is turned off. It should also cut the current when the starter motor is activated. (A cigarette lighter is the first place to look although auxillary sockets may be live all the time.)

The regulator on your alternator will ensure the battery isn't charged at a too higher voltage.

[P @ F]

Thanks for that Spruce , top advice as usual , but i have come to the decision of getting another cheapie 85 amp and running it with what i have set up so far , this is purely for ease , plus the fact that i am not confident enough to start hacking into the van electrics just yet !
My brother runs what i think you have described with the relay from his starter bat to another starter bat for his system , and to my knowledge he rarely removes the bat to bench , but he does a lot of miles in the van for one reason or another , i dont so i have not had him fit me up the same , lets not forget that i started all this to find the answer as to if solar could be an all year round option for a one man band .
Plus 2 reasons for the repeat cheapie battery are ....... 1 . I'm tight
                                                                                                                    2 . I would rather kill a cheapie than a Numax .

[P @ F]

Todays results are as follows , with a knackered battery that was benched overnight , not rested and reading at 13.5 V at 10am.

Solar on at 10am - 13.5 volts
Solar off at  2pm  - 12.9 volts

9.5 Amps in  with 9.0 Amps out , The battery has rested now since 2pm and i have just taken a reading of 12.6 volts .

I have watched the solar controller regularly during these times and the battery has been bulking with pump running , and a mix of absorb and float with pump stopped , today was nice though so with this in mind i think that the new battery and a not so nice day will answer what i am looking to achieve .

[P @ F]

Just been out to pop the battery on charge , still at 12.6 volts , put the crocs on and the smartcharger went straight to float , 12.6 is 75% cooked i think , anybody want to buy a battery with 1 careful lady owner 

[P @ F]

Today i used the same duff battery but the weather was poop , did not see the sun once .

Solar on 11am - 13.4 volts
Solar off 2pm   -12.6 volts

4 amps in with 6 amps out , not sure what the voltage is now as have treated myself to a Numax XV24MF , its a lot heavier than the budget battery i was using , i have just realised its sealed though , what is the crack with charging it , i have settings for sealed and standard batteries on one of the chargers , does it have to be done on the sealed setting or what ?

[P @ F]

Well i fitted the Numax battery today and what a difference , i was not hoping the sun would come out to give me a power boost , I worked from 10 to 3.30 , the solar took 10 amps in and the pump and power reel took 13 amps out , so on paper i used 3 amps all day , i decided to put the battery on the smart charger on the sealed setting to see what it would put back in , it took 2 hours to get to float mode , sealed setting provides 3.5 amps an hour , so 7 amps went in to make up the 3 amps taken out , not exact maths but close enough for me , after doing some sums i worked out that i got home with the battery at 90% charged  .
I think its going to be a case of looking at the weather on each day and looking at what has come in and gone out , summer running is going to be a breeze with not having to remove to bench , winter is going to be touch and go , but saying that i am confident that i will only have to bench it once maybe twice a week , time will tell !

[CleanClear]

Today i used the same duff battery but the weather was poop , did not see the sun once .

Solar on 11am - 13.4 volts
Solar off 2pm   -12.6 volts

4 amps in with 6 amps out , not sure what the voltage is now as have treated myself to a Numax XV24MF , its a lot heavier than the budget battery i was using , i have just realised its sealed though , what is the crack with charging it , i have settings for sealed and standard batteries on one of the chargers , does it have to be done on the sealed setting or what ?

My understanding is that the sealed batteries charge at a lower rate to avoid producing sulphur smells or whatever, or what we'd just call cooking the battery a bit. These are designed with being installed in mobile home/ caravan interiors etc.... so no smells etc...

Not sure if i'm misunderstanding something here.... whats this..solar on xxx  , solar off xx  i thought you're meant to just leave it on so its charging before you even get to your van, and other way round at the end of your day ?

[P @ F]

Today i used the same duff battery but the weather was poop , did not see the sun once .

Solar on 11am - 13.4 volts
Solar off 2pm   -12.6 volts

4 amps in with 6 amps out , not sure what the voltage is now as have treated myself to a Numax XV24MF , its a lot heavier than the budget battery i was using , i have just realised its sealed though , what is the crack with charging it , i have settings for sealed and standard batteries on one of the chargers , does it have to be done on the sealed setting or what ?

My understanding is that the sealed batteries charge at a lower rate to avoid producing sulphur smells or whatever, or what we'd just call cooking the battery a bit. These are designed with being installed in mobile home/ caravan interiors etc.... so no smells etc...

Not sure if i'm misunderstanding something here.... whats this..solar on xxx  , solar off xx  i thought you're meant to just leave it on so its charging before you even get to your van, and other way round at the end of your day ?

I switch it on and off for the research purpose really , plus the watt meters i use are not self powered , 3 of them in total , if i left them on it would be a drain on bat , as it is i dont miss much sun before i start and i take the readings at start and finish of cleaning to get an accurate measure of what is in and out , after i finish i get a fair bit more on the solar in side of things which is a big bonus , as i said todays full work set me back 3 amps , but i switched it off for the bench charge test when i got home .