solar panels and regulator.Do they keep your battery fit?

[plumbersvan]

:-D I have a 120w solar panel which i,s im told,regulated. :'( I found during the very grey days of late my batteries were down to 11v or worse 8-)

 

I had an idea *-) I bought an electric meter to mesure the voltage,amongst hundreds of other funtions,cost 7€ :-D

 

I found a 1volt drop between the meter(near the solar regulator)and the battery.Cleaver really,very pleased with myself :-D

 

Then i cut of the leads and fitted a plug and watched the voltage as the sun came out.In the dismal grey rain soaked veiw the meter showed 12v eventualy getting to 13.8v when the regulator cut off the solar charge 8-) Black cloud voltage 12.xv going up as the black became grey.I had another idea :-D

 

I turned off the solar panal,the battery voltage dropped back to 11.4v Panel on 12.xv once again sun or lighter sky :-S And 13.6v panel off voltage droped back to 11.8v *-)

 

Evenings i always had power though when i wanted to charge the old laptop the volatge would drop to 10.6v 8-)

 

I then bought a screw driver,and removed the solar panel wire from the regulator connecting it directly to the battery(with a plug into a socket :-D Quite clever i though)

 

During the lighter grey day the meter showed up to 15v in the black that fell to 14.xv that night my battery was fit and healthy,with laptop charging and watching a film the meter showed 12.7v dropping by midnight with radio on,to 12.2v(the radio needs 11w it says)

 

As most campers watch TV all evening which as far as i can see uses about 60w with sat bax and flat screen TV how do your batteries do??

 

How many pannels do you have?And dose your regulator cut the charging off at 13,8v?If so no matter how many panels you have the batteries wont charge.

 

Im now buying a 30w panel which will be direct to the battery with the 120w on standby via the regulator

 

Electrical people at the garage spoke of "gassing"but i have sealed batteries?How offten will they have to be unsealed to top them up???

[crinklystarfish]

Possibly simpler all round to move from France to somewhere where it doesn't rain so much.

[sshortcircuit]

If you are now connecting your solar panel direct to the battery I wonder why they manufacture regulators?

 

I suppose if its the 30w panel it may be ok ??????

[Guest Tracker]

When was the solar panel last cleaned, as a dirty panel will not collect light as well as a clean one?

[plumbersvan]

Clean quite clean anyway.

 

I thought a 20/30w panel would top the batteries up & i often thave a battery or laptop on charge during the day which seems to keep the voltage around 13v.When the suns out even with a radio on laptop charging the 120w panel registers 16v when direct 8-) And i disconect it

[lennyhb]

Firstly you should never use a solar panel without a regulator, the panel in good sun will give out about 20 volts. With a sealed battery you should not have have a potential of more than 14.2/14.5 v across it (dependent on type of battery), it may be sealed but they have a safety valve.

The potential across the battery will only come up to the max of 14.2v as the battery reaches a state of full charge (internal resistance rises as the charge level increases).

 

You don't say what type of battery you have, to get a full charge a wet cell or AGM battery once up to 14.2 v needs to be held there for about an hour before dropping to 13.8 v for a maintainance charge. If it's a Gel battery it needs to be held at 14.2 v for about 8 hours before reducing to 13.8 v.

 

Is your battery past it's sell by date i.e. once fully charged will it hold the charge and give the level of performance similar to when it was new?

 

Assuming the panel is clean are the cables from the panel to the regulator of sufficient size to reduce the volt drop to a minimum if you have say a 5 metre cable run from the panel to the regulator with a 120w panel you need at least 6 mm sq cable absolute minimum 4 mm sq, if the cable run is longer than 5 metres you need even lager cables. The regulator should be as close to the panel as possible with the 1 v drop you are getting it sounds like the cable is too small or the regulator a very long way from the battery.

 

From your readings only 15 volts into the regulator and a 1 volt drop between regulator and battery it sounds like the cables are far too small, rewiring with correct size cables should solve your problems.

[RogerC]

Electrical people at the garage spoke of "gassing"but i have sealed batteries?How offten will they have to be unsealed to top them up???

 

You don't 'unseal' or top up sealed for life batteries ......once dead they are dead.  Batteries 'gas off' during charging because of the chemical reaction within the battery which generates oxygen and hydrogen.  This  becomes an 'explosion hazard' if the battery is charged to quickly or is overcharged hence a regulator is sometimes required if a solar system is fitted..  Therefore in normal circumstances (with a regulator fitted where required/advised) this is not an issue.  During charging the battery will vent either through a vent pipe or a specialist built in valve.

[Guest Tracker]

To check if the battery is duff or OK you will need to disconnect everything from it and then check the voltage - preferably after leaving to settle or stand disconnected for a few days but I appreciate that whilst you are living in the van that might not be possible - so an instant readout and perhaps another after an hour or three if you can leave it that long might help determine.

 

You are looking for a no load voltage of about 12.7 for a fully charged battery and anything much below about 12.3 can be considered as suspect.

 

If the battery is of unknown age it may well be past it's retirement date but before replacing it do check that all fuses and connections are clean and tight with no heating up when under load.

 

 

[plumbersvan]

:'( Had a dreadful day.i dont think i really wanted to unplug my camper loose the wi-fi & Leave

 

I reversed to the grey water with the engine raceing &clutch smelling :-S Then i hit a high concrete side which was hidden by grass 8-) Finaly forward backwards and found the water filler on the wrong side?Moved again hit a tree-----

 

Emptied and filled with water couldn't find adapter??Filled useing a 5 liter bottle took hours.Leaving.at the barrier my foot slipped off the clutch and i almost demolished the barrier *-) *-)

 

Good advice,plugged in at the camping where i tried the solar panel,watching the voltage with care.at mid day once disconnected it showed 13.4v? By 14.30 when i began my disastrous demolition departure it shower 12.8v which i thought was to low :-|

 

Your posts have cheered me up :-D

 

Back in the supermarket cafe with wi-fi

[Guest Tracker]

plumbersvan - 2012-04-26 3:08 PM

Good advice,plugged in at the camping where i tried the solar panel,watching the voltage with care.at mid day once disconnected it showed 13.4v? By 14.30 when i began my disastrous demolition departure it shower 12.8v which i thought was to low :-|

 

Au contraire! 12.8 volts is what a fully charged battery in good condition should be showing!

 

On the other hand having immediately come off charge pretty well any battery would show 12.8 volts!

 

It needs to stand disconnected for a while to be able to tell.

 

You could check the voltage after dark and without ehu and again in the morning before daylight - unless you disconnect the solar panel in which case you will get a more realistic reading.

 

Perhaps a converted armoured personnel carrier would be more suitable for you if you intend to carry on demolition work as a sideline!

 

 

[lennyhb]

Blimey! I'll keep my distance when you are around, hope you didn't do too much damage.

 

With the panel giving an output in sunshine providing there is not more than a light load on the battery it should be reading 13.8 volts unless your regulator turns off completely when charged then it would be 12.8 as Rich says.

 

Sounds like either battery RIP or undersized wiring or even both.

[davidmac]

Before I retired I was a carpenter Not an electrician so perhaps on the wrong track.If in strong sunlight the regulator switches off the solar charger would it not be possible to cover part of the pannel to keep the voltage under the cut off point.Running up and down onto the roof to adjust the cover as the sun waxes and wanes would also provide you with a good fitness program as a bonus.

Regards David

[Caddies104]

We once considered Solar, but enjoy the luxury of EHU too much, your post just confirmed it, hope you are OK, made me laugh but I guess you didn't at the time!!

 

 

[plumbersvan]

All this rain is having bad effects :-S I drove across town and had a feeling my camper was not its normal self :'( Just as i arrived at this shopping cent it stopped i could just roll onto a parking :-S

 

The rain didnt stop,after a short pause it started :-D And im now parked in the garage workshop parking :-D

 

I wonder what went wrong?Rain?I was told to try "WD40" which i now have and will spray every where.In the worst case i could stay hear forever 8-)

 

Or another week which is when the garage can give me an appointment 8-) I think it should be ok to get to the aire

 

Solar panel dose need its regulator,having removed the wires :-D and connected direct i found i couldnt leave to go to town just in case the sun poped out(which it didnt)now my battery is at 12.2v and drops to 11v when i put the radio on or use the 12v laptop charger

 

When the holidays are over(when do the French work they have far to many holidays)ill check into a camping plug in order another regulator i found online,which allows charging up to 13.9v ,it says

[sshortcircuit]

plumbersvan - 2012-04-28 1:10 PM

 

All this rain is having bad effects :-S I drove across town and had a feeling my camper was not its normal self :'( Just as i arrived at this shopping cent it stopped i could just roll onto a parking :-S

 

The rain didnt stop,after a short pause it started :-D And im now parked in the garage workshop parking :-D

 

I wonder what went wrong?Rain?I was told to try "WD40" which i now have and will spray every where.In the worst case i could stay hear forever 8-)

 

Or another week which is when the garage can give me an appointment 8-) I think it should be ok to get to the aire

 

Solar panel dose need its regulator,having removed the wires :-D and connected direct i found i couldnt leave to go to town just in case the sun poped out(which it didnt)now my battery is at 12.2v and drops to 11v when i put the radio on or use the 12v laptop charger

 

When the holidays are over(when do the French work they have far to many holidays)ill check into a camping plug in order another regulator i found online,which allows charging up to 13.9v ,it says

 

Before you continue bodging about with new regulators and whatever it would be better if you can get your battery checked first as from what I have read it appears goosed. No point in fitting a new regulator to an existing problem (>) :-D :-S B-) :'( :-( (lol)

[Guest Tracker]

Solar regulators are very reliable and I would suspect the battery, or it's connections and fuses, as being your prime culprit.

 

If you get the battery checked or even just buy a new battery and it does not cure the problem then is the time to start looking elsewhere.

 

Keep the old battery until the case is proven and if it is still OK a spare with jump leads can be handy and if it is duff then chuck it out when you know for sure.

 

By the way your postings would be easier to read without all the smileys dotted about - thanks.

[Guest pelmetman]

Tracker - 2012-04-28 3:25 PM

 

By the way your postings would be easier to read without all the smileys dotted about - thanks.

 

8-).................Nothing wrong with a few smileys Rich ;-)............. :D............... (lol) (lol) (lol)

[sshortcircuit]

pelmetman - 2012-04-28 3:31 PM

 

Tracker - 2012-04-28 3:25 PM

 

By the way your postings would be easier to read without all the smileys dotted about - thanks.

 

8-).................Nothing wrong with a few smileys Rich ;-)............. :D............... (lol) (lol) (lol)

 

I totally agree and you have reinforced my point :-D :-D :-D

[Dr Dave]

Just a quick heads up on relying on the battery voltage to indicate the state of charge its o/k (but not ultra accurate) when the battery is in serviceable condition,however when the plates are sulphated up and the capacity has been reduced its terminal voltage is very unreliable to indicate state of charge. For example a battery that has passed its best and has sulphated plates has a higher internal resistance plus drastically reduced capacity and will display the following characteristics. When load is placed on the battery the terminal voltage will drop quite quickly as the battery is unable to sustain the current drain. When the load is removed the voltage will rise again and when the solar panel ormains charger is active the terminal voltage will rise quite quickly to 13.8 or 14 volts as there is no capacity to absorb the energy the charger is supplying even though the terminal voltage may indicate full charge. The effect of this is that you have a flat battery as indicated by terminal voltage after minimal current drain. However the same battery will indicate that it is charged quite quickly after a short charging period. A useful check is if the battery is discharged it should take approximately the capacity (in amp hours) of the battery divided by the current that the charger / solar is supplying so a 100ah battery charging at 5 amps expect over 20 hours to charge and reach 13.8 Volts.Anything less the terminal voltage is misleading you. And regarding a one volt drop in the cable from the solar charger to the battery will have the effect of causing the solar regulator to stop charging when the battery terminal voltage is 13.8 volts minus the one volt drop so 12.8 volts at the battery terminals then regulator will the go into a pulsing mode as when it stops charging the voltagedrop in the cable reduces due to less current flow and it will try to charge again ad infinitum so keep any voltage drop between solar regulator and battery to an absolute minimum.