Winedineroam Posted November 6, 2019 Author Posted November 6, 2019 Derek I just saw your last reply, thanks a lot for this, it all makes perfect sense. Really appreciate your explanations and I’m looking at that link right now. Thanks again
Winedineroam Posted November 6, 2019 Author Posted November 6, 2019 Useful link thanks Keith, I’m picking it up gradually, already much better informed than I was when I submitted my post! Be careful of being open to more questions, I’m sure I’m not done yet ;-)
Alanb Posted November 6, 2019 Posted November 6, 2019 I have always regarded charging from the vehicle alternator to be the most important method of motorhome/campervan habitation battery charging, but it does require a considerable amount of driving time in order to be effecive. Alternator charging can be improved. The simplest and least expensive method is probably to increase the size of the cables carrying the charging current. (The current carrying capacity of cables relates to the ability of cable to carry the current without overheating. However when this rating is applied to 12V systems, it results in a disproportionate voltage drop along the cable.) In 12V systems saving a fraction of a volt can result in a considerable charging improvement. Original habitation battery cables are often 6 sq mm, as this is adequate to prevent overheating, but increasing to 16 or 25 sq mm can provide a large improvement in charging rates. Further improvements can be made by installing a battery to battery (B2B) charger. These are not cheap and their installation should not be undertaken lightly. In sunnier seasons, the choice of solar regulator is another route to improvement. There are others with considerable experience in this area, but a maximum power point tracking (MPPT) regulator is generally advised. Alan
spirou Posted November 6, 2019 Posted November 6, 2019 Winedineroam - 2019-11-06 7:15 PM Regarding charging I have been using a 16amp EHU Cable(1.5mm) with an adapter and plugging into a regular socket at home. I'd be v happy to find out there's a better/more efficient way of doing it. I risk stating the obvious but a cable doesn't do anything without a charger no matter how thick it is. You might have a 16A cable but that's not the same as a 16A charger. Yes, most people plug into their home/garage socket, 1.5mm or 2.5mm cable won't make much of a difference to that end of the equasion. The problem, looking at your original post, is that the charger doesn't seem to be doing much with the electricity coming to it through that cable. As stated previously, it would be useful to know what charger it is. At least the brand would be a step forward. Schaudt, Votronic/Buttner, CBE, Reich, Victron, Calira, CTEK are some of the more commonly seen in MH environments. A control panel should already be a decent clue to what you have. The voltage you should be seeing after a few hours of charging (solar or EHU) should be somewhere above 14V (14.4 most commonly) The difference of half a volt might seem irrelevant but even 0.1 makes a difference. After 6-12h or so the voltage will probably go down to 13 8 as the charger enters the float phase.
mikefitz Posted November 6, 2019 Posted November 6, 2019 Hi Lisa, Thanks for the kind words. There are three ways the leisure batteries are charged, from mains when plugged in via the cable you have, from the engine alternator when the engine is running, and from the solar panels. In your van there will be one or more units that control these charging processes. If you could identify these it would help advising what control settings are need and what information is displayed , like battery voltage, and how this information will help you looking after the system. There are several manufactures and types of the control units, some are more capable than others in keeping the batteries in top condition. Some are simple with no user control whilst others need user set-up for optimum performance. The mains charging unit will function when you connect your cable to your home power point. A safety issue here exists if house or garage socket is not protected with a RCD, if you are unsure then use a plug in unit available from places like B and Q, https://www.diy.com/departments/diall-13a-rcd-adaptor-plug/800774_BQ.prd The mains charger unit in your van, at the end of the mains cable, will convert the house mains into a low voltage slightly higher than the voltage of the leisure batteries and 'push' energy into the batteries. However as the batteries become charged they 'push' back, so the amount of energy that goes into the battery becomes smaller and smaller as the batteries become full. The whole process takes time for a flat battery, even with a powerful charger it will take 5 to 6 hours, and with a less powerful charger it will take much longer. The charger will have a maximum power and the 'push' voltage may be fixed for a basic charger or have 3 or more 'push' voltage levels for a more complex charger. In addition these voltages may be user selectable for different battery types to ensure optimum charging. The solar charger performs in a similar way but here the amount of energy is dependent on the amount of sun energy. There are two basic types of solar controller electronic design and the difference in performance can be significant between different makes and type. It is important that the solar panel characteristics are matched to the controller design for best performance. The more expensive types of controller allow user set-up for the battery type. When the engine is running nearly all motorhome systems connect the leisure batteries by electrical devices to the engine battery, so the engine charges the leisure batteries. Depending on exactly how this is implemented, the performance can vary from very good to poor. Even the best systems take a few hours to top up a partially discharged battery and a typical system will take several hours or more. Its useful to be able to monitor the battery condition and there are battery ' fuel gauges' that can be fitted that will tell you the charge condition of the battery. Even a voltmeter will give some idea of the state of the battery and help identifying how the chargers are performing. For example a voltage of 12.7 to 13 (no charging or loading) is an almost full battery. Under charge conditions a voltage of in excess of 14 volts should be seen at some stage of the charging process. You may have documentation on the charging and control units fitted or they may be model codes on the units. Posting this information will help with advising how to get the best performance or in the worst case suggesting alternative control systems. Mike
Derek Uzzell Posted November 7, 2019 Posted November 7, 2019 Winedineroam - 2019-11-06 6:53 PM Absolutely correct. And I think my conversion guy has done a decent job, a lot of my questions come from a lack of basic knowledge and experience but I’ll get there. Cheers Derek There’s advice on motorhome habitationn electrics here https://www.outandaboutlive.co.uk/motorhomes/articles/practical-advice/motorhome-advice-a-beginners-guide-to-habitation-electrics but I believe your best bet for generalised technical background (not just electrics) would be to get hold of a copy of the late John Wickersham’s book “The Motorcaravan Manual”. The 3rd edition should be obtainable secondhand on-line for about a tenner and earlier editions even cheaper. https://www.amazon.co.uk/Motorcaravan-Manual-Choosing-Using-Maintaining/dp/1844250474 (Or your local library may be able to obtain the book on loan.) The trouble is that significant details of your Citroen Relay-based camper-van’s conversion remain unknown. You’ve said which leisure batteries, fridge and inverter are fitted, but that still leaves the make/model of battery-charger (that should have a substantial power-output to cope with the two leisure-batteries) and the equipment forming the basic habitation electrical system that will include 12V and 230V fusing, electrical power-handling and a control-panel with switches and gauges (that I assume provided the 13.5V and 12.7V figures you quoted above). If you’ve commissioned your camper-van and you’ve got questions about how the conversion functions, the limitations of the conversion and whether how you’ve being using it should be expected to produce the results you’ve described above, the converter should be able to help with those questions. An alternative would be to get someone with sufficient expertise to inspect your camper-van and offer a realistic opinion on how the conversion has been carried out and its capabilities - but the converter should be the first port of call.
Winedineroam Posted November 7, 2019 Author Posted November 7, 2019 Hi Lots more useful info thank you. The charger in the van is a Sargent EC160. I'm going to try and attach a photo of the control panel (failed to upload last time). The solar power controller is a CM324Z Lisa
Robinhood Posted November 7, 2019 Posted November 7, 2019 ....I think the solar regulator is probably a CM3024Z, the specs for which are somewhat sketchy, but appears to have a max charge voltage of 13.7V, and should handle up to 360W input. The Sargent EC160 charges at 13.8V, and is has a maximum output of around 11amps. Both charging methods are very simple, and use lower voltages than I would like to get the best out of the batteries. The battery bank is also large for the charging you have available, and the charging system(s) will be being "tested" by your usage. The electrical system could be described as "entry level". Nonetheless, the use you're getting (as described) is rather less than I would expect from the equipment as set out - if the batteries are in good condition and fully charged before use. If we disregard solar, your seven hours of charging on EHU is going to replace not much more than half the potential contents of one battery; in reality, I'd suggest you charge for at least 24 hours before next going off-grid. That should ensure batteries as close to "full" as you are going to get as a starting position. Then, ensure the inverter is turned off when not in use, minimise the number of lights used to that you practically need, and turn the thermostat on the fridge to an appropriate (only as cold as necessary) value. That should give you a decent baseline of potential usage. (The one thing we haven't considered so far is whether the split/charge from the alternator is working properly. If it isn't then the compressor fridge is likely to be depleting the leisure batteries whilst on the road, adding another unaccounted for drain).
Winedineroam Posted November 7, 2019 Author Posted November 7, 2019 Thanks so much for this RH, and yes you're right its a CM3024Z (my typo) I'm not only following your advice I'm copying all useful replies into a document for future reference and in case I ever need or want to upgrade the electrical system. Not an option right now but maybe one day. Any thoughts on how I would check if the split/charge from the alternator is working properly? I have a friendly garage on my road - I guess they could test it for me?
Winedineroam Posted November 7, 2019 Author Posted November 7, 2019 Thanks Derek You're absolutely right and my converter guy has been very helpful, trouble is it's only now I'm figuring out the right questions to ask and I didn't want to keep going back to him ad hoc so I decided to try and increase my base knowledge THEN ask him a bunch of relevant questions in one hit. In a reply to another helpful person on here, I mentioned that the charger is a Sargent EC160 and the solar controller is a CM3024Z and received some interesting info on both. I can't tell you what else forms the basis of the electrical system though I could find out if necessary. Cheers for the useful tips including the book. Lisa
colin Posted November 7, 2019 Posted November 7, 2019 As regards the 240v system, do you know yet if it works independently of the invertor, i.e. the sockets are powered on EHU with the invertor switched off? If so (and it should be) you might be better off having a (heavy duty) cut off switch to invertor as some of them use power even if their own switch is off.
spirou Posted November 7, 2019 Posted November 7, 2019 Winedineroam - 2019-11-07 4:05 PM Any thoughts on how I would check if the split/charge from the alternator is working properly? I have a friendly garage on my road - I guess they could test it for me? Check the leisure battery voltage before starting the engine and with the engine running. If it rises then it works. How well the wiring copes with the load will be clear if you then turn on the fridge (and any other loads if you wish to really stress test the system) and see how much the voltage changes. If it suddenly drops a lot (more than about 0.2V) then the wires connecting the starter and leisure batteries could use an upgrade to a bigger cross section. I would consider 10mm2 as the minimum, bigger is better. PS I should mention that running more than the fridge while you're driving probably isn't common so turning on everything else will be beyond a reasonable load.
Derek Uzzell Posted November 7, 2019 Posted November 7, 2019 Winedineroam - 2019-11-07 3:13 PM ...I can't tell you what else forms the basis of the electrical system though I could find out if necessary. My Rapido motorhome's 230V circuit-breakers and its 12V fuses are housed in individual pieces of equipment: there’s also a separate battery charger and a separate control-panel that carries switches and gauges. But your campervan’s Sargent EC160 has all those elements combined in a single unit. So no need to investigate further as all the basic habitation electrical ’stuff’ is in the EC160.
mikefitz Posted November 8, 2019 Posted November 8, 2019 The Sargent EC160 is intended for 1980 caravans with a single battery. It will never fully charge your two batteries in a reasonable time. The CM3024Z solar regulator is basic and will not recover the full power from the solar panels, in ideal conditions it will supply around 150 watts to the batteries. ( assuming the panels are nominal 20 volt panels). The EC160 also looks after engine charging with built in relay, the capability is poor and unlikely to correctly charge the leisure batteries. I had hoped that the converter had used quality items but in my opinion the system you have is borderline for an installation using an inverter and compressor fridge. I am concerned, given that the lowest cost items were installed, that the 230v mains installation may not be up to the standards required. I recommend you have an Electrical Installation Condition Report (EICR) carried out. Whilst on the subject of safety it may be prudent to have a gas safety check carried out. (assuming you have gas appliances fitted). The best advice would be to replace the EC160 and CM3024Z with quality items, more about this later. In the short term it's possible to adjust the settings on the solar controller to get better charging, there is information, instruction manual and some YouTube video, on the internet. The 'real' CM3024Z has a current monitoring facility built in, most of the units available are lower cost copies and do not perform as well. What they all do is allow you to set the voltage that the controller applies to the batteries, by means of the buttons you can cycle through the settings and change values with the + /- buttons. The setting you may need to change is ' PV off '. This sets the maximum voltage that the controller will apply to the batteries. Ideally for your calcium leisure batteries this should be at least 14.4 . Correct charging control should reduce the voltage to a lower level, say 13.6 volts once the 14.4 voltage level has been reached. Unfortunately all the CM3024Z controllers I have encountered fail to drop to the lower level, this can lead to over charged batteries is some situations. The work round is to set a lower voltage, say 13.8 if the van is unattended, but to use the higher level if using the van, keep note of the battery voltage and manually select the lower value once 14.4 volts is displayed on the unit. In the medium term replace the solar controller. This will be easy to implement as it will directly replace the existing unit. I recommend the Victron Smart Solar Controller, https://www.victronenergy.com/live/victronconnect:mppt-solarchargers For your panels the 100/20 model would be required. This will take the full power from the panels and correctly charge the batteries, very easy to set up. In my tests this controller was able to generate over 30% to 40% more from the panels compared to the CM3024Z , ( and it 'talks' to your phone). This is the most cost effective method of utilizing your solar capacity and may just make your system viable. The quality solar controller will overcome the short fall in performance of the EC160. Longer term add a quality mains charger and keep the EC160 for its 230v mains control and protection. Mike
Winedineroam Posted November 18, 2019 Author Posted November 18, 2019 Hi Mike Apologies for radio silence, its been quite a week. Thanks for all this advice. I was disappointed - obviously - to learn that some of my kit isn't the best quality for the job, but right now I can't do a lot about it. I'm going to have a look and see if I can change the settings on the solar controller and before I go away on a long trip next spring I'll consider upgrading it as suggested. In time maybe the charger too. Meanwhile I've had another overnight in the van and managed the electrics much better overall. Now I have another more immediate problem so I need to find an expert on thetford toilets!!
Derek Uzzell Posted November 18, 2019 Posted November 18, 2019 On this forum there will be plenty of knowledge/experience of Thetford cassette toilets (recent enquiry here) https://forums.outandaboutlive.co.uk/forums/Motorhomes/Motorhome-Matters/Thetford-CS200-leaking-feeder-pipe/53698/#M627715 If you want forum advice about your toilet, it would probably be better if you started a new forum discussion rather than extend this one. There is a number of Thetford cassette-toilets (both bench or swivel-bowl models) so, besides providing details of the current problem, it could be helpful if you could identify which Thetford toilet model your camper has. (If you don’t know, don’t worry - just start by saying if it’s a bench or swivel-bowl type.) There are photos here that may help - what the cassette looks like is a reliable identifier. https://www.thetford-europe.com/gb/products/toilets/cassette-toilets
Recommended Posts
Archived
This topic is now archived and is closed to further replies.