witzend Posted July 9, 2018 Share Posted July 9, 2018 Can you over Solar my panels keep the batterys up to 14.4 volts when van is out of use can this cause any harm to batterys Link to comment Share on other sites More sharing options...
aandncaravan Posted July 9, 2018 Share Posted July 9, 2018 I think it depends the the efficiency of the Solar set-up and the batteries used. Some batteries will half tolerate long term over charging ok, others will be damaged quite quickly. The Yuasa website states that Leisure batteries kept on a permanent 'float'/'trickle'/'maintenance' charge, "will result in internal degradation of the battery". Even when used with, "a well-controlled charging system". As a result they suggest that batteries treated this way should be regarded as having a maximum two year life. See this extract : Battery Maintenance in Non-Automotive Float Applications 1.Typical applications are motor-generators, stand-by applications etc. The Leisure Battery range is recommended for these applications; standard vehicle batteries are not suitable. 2. Batteries used in these applications should be changed every 2 years or more frequently. (Continuous charging, even from a well-controlled charging system, will result in internal degradation of the battery). For full text read here : http://www.yuasa.co.uk/info/technical/need-know-batteries/ Additional evidence to support things are not well with all Motorhomes in this respect is the tale with Banner Energy Bull batteries. The Banner Energy Bull Wet battery seems to be prone to fluid loss in normal circumstances, but this seems to be much worse when on long term charging, either by connection via EHU or Solar power. Back in 2014 the Roadpro website was stating that the Banner Wet batteries were Maintenance free, “Banner Energy Bull” batteries don’t require maintenance in normal use" However, as of November 2016 the Roadpro website had changed to warn of high fluid loss when used : "'...... with a solar panel, a battery to battery charger or a mains charger that's on for days at a time, the electrolyte levels of Energy Bull batteries must be checked on a regular basis". Normally, excessive fluid loss is a sign of overcharge, losing a lot of fluid when on Solar and long term mains charging is strong evidence that long term charging from Solar/EHU affects batteries. While the Banner Energy Bull has clearly been highlighted, the issue affects almost all Habitation batteries to some degree or other. Note also that as of 07/04/2018 the Banner website was stating that their Banner Running Bull AGM batteries should not be left on charge for idle periods longer than 7 days at a time or the battery life will be shortened, even on a low float voltage. The FAQ page has an item : "What values should I use when setting an external charger for AGM batteries in the caravan? How high should the charging and float charge voltage be? Please employ the AGM setting, which means that the charge voltage should be set at max. 14.8V and the float charge voltage at 13.5V. Best of all, use an IUoU characteristic with temperature compensation (should you have this setting available). In order to obtain the maximum service life from your battery. Please "ensure complete separation" from the on-board supply (charger) when the vehicle is not in use >7 days. The Banner Battery advice re AGM batteries is reiterated by almost all big battery manufacturers, that AGM have short lives on long term EHU or Solar.. If you want more evidence - Victron Energy are also suggesting that the 13.8v charge voltage of the average motorhome charger will shorten a batteries life. The 'Victron Energy Unlimited' document suggests a maintenance charge of just 13.0v - 13.2v. So a permanent 14.4v looks dangerously damaging? In installations where batteries are kept on permanent charge, like UPS battery backed installations for Hospitals, Data Centres, etc the recommended maintenance/trickle voltage from the Battery manufacturers is between 13.0v and 13.2v. Schaudt's latest LRM1218 Solar Charger has dropped the Maintenance charge down from the previous units 14.2v maintenance charge to just 13.4v. Victron Energy's own new range of chargers now Maintenance/Float/Trickle charge at 13.2v, suggesting as per other documents now surfacing, that long term Solar/EHU at the usual Chargers 13.8v (or higher) will have consequences. . Link to comment Share on other sites More sharing options...
witzend Posted July 9, 2018 Author Share Posted July 9, 2018 Thanks for taking the time to answer my question so thourghly guess it,ll pay to cover the panel during lay ups Link to comment Share on other sites More sharing options...
aandncaravan Posted July 9, 2018 Share Posted July 9, 2018 If you put a fuse holder between the Solar panel and the regulator, you can just remove the fuse when the vehicle is idle, putting it back in for 2 days at a time when necessary. Obviously as you get towards mid winter, the 'over charge' will probably become 'under charge' as the days are so short. Through November, December and January maybe leave it permanently connected as the days are so short and cold there is unlikely to be an overcharge. It might even be beneficial to add EHU for a day or two? Link to comment Share on other sites More sharing options...
witzend Posted July 9, 2018 Author Share Posted July 9, 2018 I have a fuse between regulator an battery but guessed it would be better to isolate reg as well and didn,t want to disturb main solar wires Link to comment Share on other sites More sharing options...
plwsm2000 Posted July 9, 2018 Share Posted July 9, 2018 witzend - 2018-07-09 6:02 PM I have a fuse between regulator an battery but guessed it would be better to isolate reg as well and didn,t want to disturb main solar wires Do not remove the reg to battery fuse without isolating the panel to reg. first. Leaving the regulator input connected with the output open circuit can damage the regulator. I have put fuses on the regulator input and output for this purpose. Link to comment Share on other sites More sharing options...
spospe Posted July 9, 2018 Share Posted July 9, 2018 The safe way to connect a solar panel regulator, is: first connect the regulator to the 12 volt battery, second connect the solar panel to the regulator. If you do it the other way round, the quite high voltage from the solar panel (about 20 to 22 volts) will trick the regulator into thinking it is in a 24 volt system. This will happen to a correctly installed system if the battery is disconnected and reconnected without first disconnecting the panel. This is based on my personal experience, because the regulators are mostly of the 12 to 24 volt type and will automatically switch to the higher voltage when it is presented to the regulator. This would mean that the solar panel would trick the controller into thinking it was in a 24 volt system and continue to charge the 12 volt battery to destruction. (just reiterating what others have said above) Link to comment Share on other sites More sharing options...
aandncaravan Posted July 9, 2018 Share Posted July 9, 2018 I would suggest that anyone who has a 24v/12v Solar Charger doesn't have one designed for a Motorhome? The best motorhome specific Solar regulators, like the Schaudt LRM 1218 or Votronic MPPT range, are 12v only operation and specifically engineered to dynamically cope with two battery banks that have very different usage. A generic 12v/24v solar charger won't have been designed specifically for the motorhome and will have design criteria such as a 50/50 battery charging split, or require the split between Habitation area battery and the Starter battery to be manually set, e.g. 90%/10% Leisure battery/Starter battery.. The best motorhome specific regulators will dynamically change the load as required. For example a split of 99/1 Leisure/Starter battery in mid summer might automatically change to 1/99 in mid winter when a starter battery with an Alarm/Tracker may require more charge than the 'static' habitation battery. Link to comment Share on other sites More sharing options...
Deneb Posted July 10, 2018 Share Posted July 10, 2018 plwsm2000 - 2018-07-09 6:19 PM Do not remove the reg to battery fuse without isolating the panel to reg. first. Leaving the regulator input connected with the output open circuit can damage the regulator. I have put fuses on the regulator input and output for this purpose. I have seen this advice given several times, but find it difficult to understand how removing the protective fuse from a Votronic regulator for instance, would damage the regulator. Surely a regulator designed in such a way that it may suffer irreparable damage if its protective fuse blows, has not been designed very well at all? Link to comment Share on other sites More sharing options...
pepe63xnotuse Posted July 10, 2018 Share Posted July 10, 2018 A basic question from someone who is non-techy when it come to electrics.... If a solar panel is disconnected(fuse pulled/switch thrown etc) but it is left uncovered and therefore still harvesting energy, presumably with "nowhere to go", this energy will just get converted to (additional)heat? ..would this pose a problem for a panel long term? or are they designed/built with this in mind? Link to comment Share on other sites More sharing options...
aandncaravan Posted July 10, 2018 Share Posted July 10, 2018 Deneb, I guess that depends on what you think the fuse is for? It might provide some protection for the Votronic regulator, but I think it's primary function is to prevent a potential fire if the Votronic suffers some issue and short circuits. The fuse would normally only fail if the Solar regulator fails first. Sadly, many, I would say 'most', Solar regulators are not very well designed when it comes to Motorhomes. If you imagine a Solar regulator working flat out supplying 10amps to the leisure battery, when someone interrupts it's path to the battery, where is all that power going to go? Spike the Regulator or maybe spike the Solar Regulator Starter battery circuit which is obviously still connected? On some systems the Solar regulator supplies it's power to the Power controller/Charger unit, like on a Sargent ECxx or Schaudt Elektroblock where the 12v goes directly into the power supply. That allows the Power controller to control all power sources, whether that be Alternator, Mains charge, Solar or Efoy. On these systems any interruption on the path between the regulator and the battery will often lead to a voltage spike into the vehicle habitation electrics, sometimes as high as 24v, which isn't going to be good for a Fridge Controller or Truma Heating Controller, etc. If a sharp interruption on the habitation battery circuit takes place, a spike might go the Starter battery circuit of the Solar Regulator where components like the Body Control ECU, Alarm electronics, etc are permanently active. If that occurs, you will really wish it hadn't when you get the repair bill. Someone who removed the habitation battery clamps while the Solar was in full flow got a bill for a Fiat ECU and other components of over £800 from the Fiat Dealer. Hence why we are trying to get everyone to fit a fuse into the Solar Panel to Regulator wiring and pull it before any maintenance is carried out. See Tip 1. here for more info : http://www.aandncaravanservices.co.uk/solar-power.php Pepe63, We had a Solar Panel on display in the 'sun baked' shop window for about 2 years that wasn't 'connected up' and it was still in perfect condition. A Solar panel only produces electricity if you 'load it', so no heat is produced if you create a break in the wiring to the Solar regulator. Link to comment Share on other sites More sharing options...
spospe Posted July 10, 2018 Share Posted July 10, 2018 aandncaravan - 2018-07-10 10:35 AM Hence why we are trying to get everyone to fit a fuse into the Solar Panel to Regulator wiring and pull it before any maintenance is carried out. See Tip 1. here for more info : http://www.aandncaravanservices.co.uk/solar-power.php This is a really good idea (to isolate the panel from the rest of the system). Sadly, many people will not realise the value of such an action and ignore removing the fuse (or not even realise it is there to be removed) before starting work and thus cause damage to the system. We live in an increasingly complex world and there are many traps for the unwary. Modern motorhomes being a good example of poorly integrated components that work sort of OK (ish) together, but react badly to being disturbed. Link to comment Share on other sites More sharing options...
aandncaravan Posted July 10, 2018 Share Posted July 10, 2018 spospe - 2018-07-10 11:01 AM aandncaravan - 2018-07-10 10:35 AM Hence why we are trying to get everyone to fit a fuse into the Solar Panel to Regulator wiring and pull it before any maintenance is carried out. See Tip 1. here for more info : http://www.aandncaravanservices.co.uk/solar-power.php This is a really good idea (to isolate the panel from the rest of the system). Sadly, many people will not realise the value of such an action and ignore removing the fuse (or not even realise it is there to be removed) before starting work and thus cause damage to the system. . Hence why our 'Tips' on Solar suggest putting a worded instruction on the battery itself not only to warn any technician, or whoever, to remove the Solar Panel isolating fuse, but telling them where it can be found. Link to comment Share on other sites More sharing options...
Deneb Posted July 10, 2018 Share Posted July 10, 2018 aandncaravan - 2018-07-10 10:35 AM Deneb, I guess that depends on what you think the fuse is for? It might provide some protection for the Votronic regulator, but I think it's primary function is to prevent a potential fire if the Votronic suffers some issue and short circuits. The fuse would normally only fail if the Solar regulator fails first. (Rest of explanation snipped for brevity) Thanks Allan, that all makes perfect sense! Link to comment Share on other sites More sharing options...
aandncaravan Posted July 10, 2018 Share Posted July 10, 2018 Deneb - 2018-07-10 11:51 AM aandncaravan - 2018-07-10 10:35 AM Thanks Allan, that all makes perfect sense! Then I think that is a first!!! Most complain they can't understand a word I say. (lol) Link to comment Share on other sites More sharing options...
plwsm2000 Posted July 10, 2018 Share Posted July 10, 2018 Deneb - 2018-07-10 8:38 AM plwsm2000 - 2018-07-09 6:19 PM Do not remove the reg to battery fuse without isolating the panel to reg. first. Leaving the regulator input connected with the output open circuit can damage the regulator. I have put fuses on the regulator input and output for this purpose. I have seen this advice given several times, but find it difficult to understand how removing the protective fuse from a Votronic regulator for instance, would damage the regulator. Surely a regulator designed in such a way that it may suffer irreparable damage if its protective fuse blows, has not been designed very well at all? Both Schaudt and Votronic make specific mention in their installations instructions of how (in which order) the solar and battery needs to be connected. Votronic emphasis the words "Never operate the controller without the battery „BOARDI" in their manual. Unfortunately I do not have detailed schematics of the internals of these regulators so I can only speculate why this is important. The regulators take a small current (~5mA) from the battery at all times which I would guess powers up the internal processor and control electronics. If you connect power to the solar input first, the processor will not be running and so the regulator may power up in an unpredictable state when the battery IS finally connected. This is not the same situation as the fuse blowing during normal operation as the processor will be running if this happens. The other possible reason is that the regulator will contain some large capacitors on the output stage. Under no load conditions, it is very likely that the output voltage will be significantly higher than when connected to a battery. For reliability, as a rule of thumb the voltage rating of these capacitors should be at least 2 times the normal voltage (i.e use a 25V rated part for a 12V system). The reliability of these capacitors will drop as the voltage increases, so leaving the regulator open circuit for any length of time, is probably not a good thing. Link to comment Share on other sites More sharing options...
Deneb Posted July 10, 2018 Share Posted July 10, 2018 plwsm2000 - 2018-07-10 12:30 PM Both Schaudt and Votronic make specific mention in their installations instructions of how (in which order) the solar and battery needs to be connected. Votronic emphasis the words "Never operate the controller without the battery „BOARDI" in their manual. I know, but Votronic also refer at least twice in their manual to replacing the fuse: "Always use replacement car fuses of the indicated capacity!" and "In the case of wrong polarity of battery 1, the internal safety fuse will be released. The replacement fuse should have the same capacity, and it should be of the same type..." which suggests to me that a blown fuse should not necessarily be catastrophic to the operation of the unit, since if it were, there would be little point in making references to replacing it! Unless, the ONLY possible way for the fuse to blow is by attempting to connect the unit to a battery with the wrong polarity, and the assumption is therefore that the solar input will not be connected at that point? Link to comment Share on other sites More sharing options...
plwsm2000 Posted July 10, 2018 Share Posted July 10, 2018 Deneb - 2018-07-10 4:48 PM plwsm2000 - 2018-07-10 12:30 PM Both Schaudt and Votronic make specific mention in their installations instructions of how (in which order) the solar and battery needs to be connected. Votronic emphasis the words "Never operate the controller without the battery „BOARDI" in their manual. I know, but Votronic also refer at least twice in their manual to replacing the fuse: "Always use replacement car fuses of the indicated capacity!" and "In the case of wrong polarity of battery 1, the internal safety fuse will be released. The replacement fuse should have the same capacity, and it should be of the same type..." which suggests to me that a blown fuse should not necessarily be catastrophic to the operation of the unit, since if it were, there would be little point in making references to replacing it! Unless, the ONLY possible way for the fuse to blow is by attempting to connect the unit to a battery with the wrong polarity, and the assumption is therefore that the solar input will not be connected at that point? Possibly, but it is also quite easy to protect from reverse connection in hardware so it is not relying on the control electronics being operational. This could be done with a single diode to blow the fuse (which may even be the recovery diode or synchronous rectifier as they almost certainly use a buck converter to step down the solar voltage). The fuse could also blow due to a battery fault assuming there is enough solar power available. The fuse on the Voltronic MPPT is in the module and may not just go to the output connector (i.e. not quite as simple as an inline fuse to the battery). If so, this does raise an issue as on my EBL220 there is another fuse (15A) between the solar reg. output and the battery. Removing this fuse would have the same effect as disconnecting the battery whereas the one on the Votronic MPPT would not (as far as the solar reg. is concerned). Maybe I should fit a slightly larger rated fuse on the EBL than in the solar controller? It would be great to see the schematics to better understand what could happen rather than just speculating. Link to comment Share on other sites More sharing options...
witzend Posted July 10, 2018 Author Share Posted July 10, 2018 aandncaravan - 2018-07-10 10:35 AM Hence why we are trying to get everyone to fit a fuse into the Solar Panel to Regulator wiring and pull it before any maintenance is carried out. See Tip 1. here for more info : http://www.aandncaravanservices.co.uk/solar-power.php After reading this knowing when I fitted my panel I followed your advice I've looked and the fuse is there. Pepe63's Question also passed my mind and You've answered that as well Thanks Again Link to comment Share on other sites More sharing options...
Kevin1946 Posted July 12, 2018 Share Posted July 12, 2018 When I fitted my 2X100 watt I fitted a on / off switch between the solar panels and the charger which means I only turn the solar on when it is needed.This also helps if you need to remove a battery you can switch it off.I also leave it off when I am on sites with EHU.It only took 10 minutes to do. Link to comment Share on other sites More sharing options...
dipsticks Posted July 13, 2018 Share Posted July 13, 2018 Having read all the posts regarding 'over solaring' (thanks to Allan and others) I have been doing it for years in my ignorance. I fitted a 12v 7 day programmable timer with a solid state relay to connect / disconnect my panels. It hardly uses any current and makes it very flexible and convenient by using the progammer or overiding it manually to reduce overcharging. Cost £21.....ebay for the bits. Link to comment Share on other sites More sharing options...
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