Solar regulator position.

iana · Guru

Solar regulator position.

iana · Guru

The diodes arrived to day thankyou Terry.
Went to Jayco here in Perth to find out about the fitting of accessories. If the accessories or changes are listed on the spec sheet, they are installed at the factory. If the customer asks for these after the spec sheet has been sent to the factory, the changes are done at the dealers workshop.
All of our changes were listed on the spec sheet, so it was a factory install.

iana · Guru

Three pictures, the first showing the junction box under the solar panel, lid having had the locating legs broken off it, and the lid gaffa tapped in position. This panel the lid was missing and the items inside are all corroded. The other panel I noticed the gaffa tape early and did some repairs to salvage the box, so still had a lid for that side. Both boxes had gaffa tape to secure the lid, thanks Jayco.

The second and third picture show the second junction box, 4x diodes installed, and the box mounted up in the fridge vent area. This job is done, only the third panel to go.

iana · Guru

The last panel has had the diodes fitted, the new regulator is ticking away (figure of speech, it is quiet) all programed up for gel batteries. Last night was the first night of unpowered camping to try it out. The batteries were all charged by 1 pm. 18 amps was the max I saw going in. To night I am going to have everything on to bring the batteries down further to see what happens.

It was clear that one of the two solar regulators was u/s, and the other I think was leaking power back out at night. My assumption is, is that the system is working much better, although I still think we will need angle panels during winter to get us through then.

T1 Terry · Guru

Good to hear it all worked out ok in the end. I think quite a few people learnt something new from the whole exercise and that is always a good thing smile

T1 Terry

iana · Guru

Thanks Terry, now the forth night self contained camping (not entirely free). Yesterday was overcast, and the battery was flat in the early hours am. I have the solar regulator (controller) set for Gel batteries, and some weird things have been happening. Yesterday the batteries did not complete their charging.

Today was brilliant, 100% cloud free sunshine, is it normal for the solar side of the power into the regulator to be initially 13v ? when the voltage measured on the solar panel no connection is 21v.
Bulk/Absorption voltage is listed in the instructions as 14.2v but the solar side of the regulator reads 13.2v.
As the sun rose the amps climbed until reaching 21.5 amps (the three panels are working), but then when I rechecked at midday, the amps had dropped to about 7.5 and the voltage to the battery has climbed to 14.4v. So I am assuming the regulator is not excepting the extra amps available (gentle charging for gel batteries), voltage on the solar side has now climbed to 21v.

At 3.00pm, the charge is now 2.7 amps at 13.6 v, so I think that is on float, yet I don't think the battery is 100% charged.

Jaahn · Guru

Hi Iana. smile

Your regulator has gone to float when it has reduced the amps and the voltage is 13.6. but whether the battery is fully charged is another story !

What method does your reg say it uses to decide when to go to float. Some just go after a set time at the regulated voltage,eg an hour. Some use the reduction in the current as the battery comes to full to trigger the change to float. Check what your instructions say because the time method may not be enough to fully charge the batteries if they were very flat.

When charging in bulk the reg connects the panel to the batteries with only a small voltage drop. So if the batteries are flatish then 13v may be the voltage into the regulator as the battery will be only 12.5 or so. Both voltages will climb till they reach 14.4 and then the regulator starts to control the current, by switching it of and on, to hold the voltage at 14.4. If you disconnect the panel its voltage will be 21, that is normal.

Jaahn

-- Edited by Jaahn on Thursday 25th of October 2018 09:54:56 PM

iana · Guru

Hi Jaahn, there is no info on how the regulator decides to go into float mode, and yes the batteries are in a sorry state by morning, same this morning. Reading info from the net, Gel batteries require a special charging program from wet or AGM batteries, and the charge time in float is considerably longer to reach full charge.
According to the info, gel batteries are very good, and can have a life of up to 10 years ---- if charged properly, but they can be damaged by incorrect charging.
Will be doing more research into our power problem. Thanks for the info.

iana · Guru

Been reading on the net, and according to what I have read, I have wired the dual batteries up wrong, could this be part of the problem I am having.

Dual Battery.png Dual batteries 2.jpg The first picture is how I have wired the two batteries, the second picture is how I should have done it, please explain why, I have an idea of why, I just need my reasoning confirmed, that I may have only been charging up one battery, with the other left in a less sate of charge.

-- Edited by iana on Sunday 28th of October 2018 12:42:29 AM

PeterD · Guru

iana wrote:
Gel batteries require a special charging program from wet or AGM batteries, and the charge time in float is considerably longer to reach full charge.

Apart from the high voltage overcharge problems with gel batteries, these batteries are equally as robust as other batteries.

Float charging is not really charging. When batteries are charged to 70% or more, all the float charging from multi stage chargers does is compensate for the natural discharge of the battery. Or in other words the float charge stage in a multi stage charger is there to maintain the battery and not charge it.

A multi stage charger commences its cycle with the bulk stage. This gives the battery the majority of its recharging. The second stage is the absorption charge. This will complete the recharging of your battery if things are working properly. In all the chargers I have had dealings with this stage terminates when the charging current drops to a few percent of its maximum rated bulk charge capacity. I know of chargers have a time limiter built in them but this is to limit the maximum time of the absorption charging. It only cuts in if the absorption charging has not gone through its natural current limiting cycle. Personally I would not use a charger that forces the absorption stage to go through a time period and not let the current drop provide the natural limiting of the absorption stage.

PeterD · Guru

iana wrote:
Been reading on the net, and according to what I have read, I have wired the dual batteries up wrong, could this be part of the problem I am having.
pictures snipped. . .
The first picture is how I have wired the two batteries, the second picture is how I should have done it, please explain why, I have an idea of why, I just need my reasoning confirmed, that I may have only been charging up one battery, with the other left in a less sate of charge.

If the connections between the two batteries are of substantial cable then the two circuits are essentially the same. The only time connecting the batteries according to your second circuit would be of any real benefit is if you are drawing really heavy currents. With the currents in most of our vans the low resistance in the interconnections does not affect the situation to any really noticeable amount.

Connecting your batteries by the first method is definitely not the cause of your charging problems. I don't think changing the interconnections will solve your problem.

Jaahn · Guru

Hi Iana smile

I agree with Peter, the wiring is not the problem if it is all well sized. Having the second method is just getting it perfect but is not necessary. The explanation why it is perfect is because the voltage across the terminals of both batteries is exactly equal. But in your case the difference may be a minimal difference.

I also agree that float is not a charging process. The charger/regulator should get the batteries fully charged, if it has the power available, in the absorbtion phase and should keep going until that happens. Float is only for maintaining the batteries fully charged in good condition without overcharging them, that is why the voltage drops down for float.

I think it sounds like your batteries may be degraded in capacity. You should really charge them up individually with a quality charger and if you want to check them then get a car light globe and see how they perform over time down to a set voltage. Do not discharge them too low and damage them.

There have been some description of this previously. Batteries are a bit of a mystery.

Jaahn

-- Edited by Jaahn on Sunday 28th of October 2018 09:27:51 AM

iana · Guru

Thanks Peter, so moving on, was also reading on the net in the US of A, a marine site about GEL batteries, and the general concensus was they would not use them, because generally they needed batteries with a faster re-charge rate. While I have read conflicting statements, which just confuses the issue, they say that Gel batteries have a higher internal resistance, and will not except a high amount of charge, but only a smaller regulated charge over a longer period, so is this correct ?. With panels mounted flat on the roof we experience a high solar input over a shorter period of time, and so we have wasted energy because of this.

Another issue is the charge voltage, I note that the charge voltage for GEL is 14.1v to a max of 14.6v, the specs on the origionaly fitted solar regulator have a voltage of 14.7v, would this have damaged the batteries over time?

PeterD · Guru

iana wrote:
1.. was also reading on the net in the US of A, a marine site about GEL batteries, and the general concensus was they would not use them, because generally they needed batteries with a faster re-charge rate. While I have read conflicting statements, which just confuses the issue, they say that Gel batteries have a higher internal resistance, and will not except a high amount of charge, but only a smaller regulated charge over a longer period, so is this correct ?.
2.. With panels mounted flat on the roof we experience a high solar input over a shorter period of time, and so we have wasted energy because of this.

3.. Another issue is the charge voltage, I note that the charge voltage for GEL is 14.1v to a max of 14.6v, the specs on the origionaly fitted solar regulator have a voltage of 14.7v, would this have damaged the batteries over time?

1.. Without knowing what batteries they were discussing I do not care to comment. This is the problem with people with axes to grind. They sound like they are working with systems involving faster charge and discharge times than we do with our systems. Were they talking of batteries with both high and low recombination rates? Japanese AGM batteries tend to have a low recombination rate and also require higher charging voltages than American AGM batteries. The American AGM batteries charge at a higher rate. Maybe the GEL batteries charging rates are similar to the Japanese batteries albeit at a lower safe charging voltage.

You have to be careful what you are reading. I tend to look for general information rather than what specialised groups discuss or what many of the manufacturers have to say unless I can find several singing from the same hymn sheet. There is an interesting bit in Wikipedia on VRLA batteries. It tends to lump AGM and GEL batteries together. There is a bit at the end that compares them with flooded batteries:

AGM & Gel VRLA batteries:

Have shorter recharge time than flooded lead-acid.
Cannot tolerate overcharging: overcharging leads to premature failure.
Have shorter useful life, compared to properly maintained wet-cell battery.
Discharge significantly less hydrogen gas.
GEL batteries are by nature, safer for the environment, and safer to use.
Can be used or positioned in any orientation.

2.. A thing often overlooked with flat mounted panels on vans is the morning and evening performance of these panels. Angled panels have a lower performace than flat panels early and late in the day. Early an late in the day the sun swings around and can be at the same latitude as the panels meaning it is at the end of the panels. Before 9 AM and after 3 PM flat mounted panels perform better than angled ones. Flat panels may only have a 70% efficiency compared with angled ones but overall there early and late performance makes up for a fair bit of the midday losses.

3.. You most likely have been drying out the electrolyte in your batteries with charging voltages that high. A change of batteries and/or regulator is necessary if you can not adjust the charge rate for GEL batteries..

T1 Terry · Guru

If the Gel batteries have been charging at a high current and to 14.7v, every chance the plates have gassed the electrolyte and formed numerous bubbles between the gel electrolyte and the plate itself. Unlike a flooded cell or AGM battery where the gas bubbles work their way to the top of the electrolyte, these bubbles are often trapped between the electrolyte and plate surface. When there is no contact between the plate and the electrolyte the plate surface becomes sulphated and no charge/discharge chemical reactions can occur through that part of the plate. The sulphated material can't be shed the same way as it can in a flooded cell or AGM cell because it can't float up or sink down in the electrolyte.
Gel batteries are great for a carefully controlled charge rate over a long period and carefully controlled discharge rate so no gassing occurs. Such a charging/discharging regime are not practical in an RV and almost impossible when relying on solar charging.
Agree with the 13.6v being a maintenance voltage and not a charging voltage, 13.8v is a trickle charge for a battery above 90% SOC and to fully charge a lead acid battery in the time period available from solar charging requires a constant 14.4v to get the last 7% or 8% above the 90% state of charge mark and this will have a reasonable amount of electrolyte gassing occurring during this last bit of charging, not something Gel batteries can handle. To get that last 2% state of charge takes about 24hrs at a constant 13.8v, not something that is practical for free camping RV use.

T1 Terry

iana · Guru

Thankyou Terry, and Peter. I have read the information posted about these batteries on the net, the information corresponds. My typo re "Float" charging.

I have noticed that the battery problems only become critical on the second day and onwards after being at a 240v site, where the batteries have been brought up to full charge. From then on its a down hill spiral, the installation of the extra solar panel has done nothing really, as these gel batteries can't accept a full charge in the daylight hours available.

Looks like Mr Jayco has done it to me again, installing batteries unsuitable for RV use, and a solar controller not designed for gel batteries, which will destroy them prematurely as an added bonus. The other thing is what battery chargers were used during the build and detailing prior to us picking the van up, I did see chargers being used.

The other thing which I find so frustrating, is that the low voltage alerts and cut outs, are set at 11.3v on the drifter, and 10.5 v for the fridge. The origional solar controller had an alarm also, the new one I have fitted does not. But it would usually go off early in the morning 2am or so, and that too was set at a low 12v setting, at that hour I didn't take too much notice of the figure.

It would seem that anyone contemplating using a compressor type fridge, and doing more than one night on batteries should think very carefuly about the design of the system. At least double the battery capacity is required (over what we have), attention to adding extra insulation around the fridge to stop it from cycling so often, and a back up system if things get bleak. Now persons are not going to start up a generator at 2 in the morning, so I don't see that as an answer.

Maybe for all of its problems a 3way fridge is not so bad after all, with perhaps a small compressor type in the vehicle for frozen stuff.

With us, I think the answer is with Lithium, but the cost is a big jump. And it is very disapointing having done all of this work to find that the system won't be staisfactory with out a big change, as we are hobbled by the weigh issue, ie adding extra batteries is too heavy.

T1 Terry · Guru

The cost between a 3 way fridge and a household inverter style fridge more than covers the cost of the lithium battery to run it and some towards the solar to recharge it. The 12v compressor fridges are a lot more expensive and not as energy efficient, but the higher voltage a lithium battery can maintain all the way down to 100% discharged certainly improves the 12v compressor fridge operation and does reduce the amount of battery/solar required.

I'll just put my helmet on and head down into air raid shelter cause I sense another round of incoming shots about me mentioning that evil word L-i-t-h-i-u-m :lol:

T1 Terry

PeterD · Guru

iana wrote:
Looks like Mr Jayco has done it to me again, installing batteries unsuitable for RV use, and a solar controller not designed for gel batteries, which will destroy them prematurely as an added bonus.

GEL batteries are eminently suitable for van use. Do not condemn them simply because the wrong battery charger or the wrong settings on the charger were selected resulting in a stuffed battery.

oldtrack123 · Guru

PeterD wrote:
iana wrote:
Looks like Mr Jayco has done it to me again, installing batteries unsuitable for RV use, and a solar controller not designed for gel batteries, which will destroy them prematurely as an added bonus.
GEL batteries are eminently suitable for van use. Do not condemn them simply because the wrong battery charger or the wrong settings on the charger were selected resulting in a stuffed battery.

Ditto biggrin

iana · Guru

An update on the situation.

Having put blocking diodes on the three solar panels 145w each, replaced the two regulators, one faulty, the other maybe, with one of higher capacity, and also replacing the wiring between the batteries and regulator with double size wire and halving the wire length, then replacing the two 100ah gel batteries with 120ah AGL batteries.

We are now up too our sixth night, no services camping, and have plenty of power, even with the TV and Vast on. So the exercise was a success.

Still think we will need angled and portable panels to see us through the winter though.

Thanks everybody for the help.

-- Edited by iana on Thursday 10th of January 2019 10:08:50 AM

T1 Terry · Guru

PeterD wrote:
iana wrote:
Looks like Mr Jayco has done it to me again, installing batteries unsuitable for RV use, and a solar controller not designed for gel batteries, which will destroy them prematurely as an added bonus.
GEL batteries are eminently suitable for van use. Do not condemn them simply because the wrong battery charger or the wrong settings on the charger were selected resulting in a stuffed battery.

If you read through the charging requirements for genuine Gel electrolyte batteries you will realise just how wrong that statement is. Unfortunately, like so many other things these days, many AGM batteries are labelled as Gel batteries in an attempt to gain an entry into another potential market.

Genuine Gel batteries have a very limited max charge/discharge rate designed to avoid hydrogen and oxygen bubbles forming between the gel electrolyte. If you think about it you can understand how these problems make a battery with Gel electrolyte now suitable for recharging via solar because of the limited charging period the sun is in the correct position to make good output. House batteries need to come up to the end of boost voltage as fast as possible to allow the max amount of time for the absorption stage to get the batteries as close to 100% SOC as possible in the limited time available.

T1 Terry

Baz421 · Guru

iana wrote:
Been reading on the net, and according to what I have read, I have wired the dual batteries up wrong, could this be part of the problem I am having.
The first picture is how I have wired the two batteries, the second picture is how I should have done it, please explain why, I have an idea of why, I just need my reasoning confirmed, that I may have only been charging up one battery, with the other left in a less sate of charge.

-- Edited by iana on Sunday 28th of October 2018 12:42:29 AM

Have a read of this keeps things simple,,,,, AND THEY TELL YOU WHY ,,,AND THEY GIVE REAL LIFE EXAMPLES,,

http://www.smartgauge.co.uk/batt_con.html

Enjoy the read

T1 Terry · Guru

That Smartgauge site and articles have come up quite few times on various forums and been challenged by the professors and engineers because it doesn't match their computer modelling. When I did the hands on testing by adding shunts between the batteries so it verified the finding, then gave the test parameters to the professors, there was no reply and the whole idea that they didn't know it all was ignored :lol:

We are planning to do a demo at this years STC to show exactly this problem and include lithium batteries in the mix to show why you can not just drop in 12v lithium batteries to replace the removed lead acid batteries and expect a good result.

T1 Terry

T1 Terry · Guru

Just as guide to those that are mounting a defence, take into account the internal resistance at cell level and battery level and you will understand why the state of charge is not the same just because the voltage is common across all the batteries in parallel.

T1 Terry

jeepnudger · Senior Member

RE: Solar regulator position.333when