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About tictag

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    Over 1000 posts
  • Birthday 31/03/1972

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  • Towcar
    Jaguar XF 3. 0 S
  • Caravan
    Lunar Stellar 2013MY

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  1. Impact driver = No Something small, cheap'n'cheerful = Yes You should easily be able to raise/lower steadies by hand.
  2. I've no experience of this unit (assumed to be a Zig 2S4V) but from what I can see from the circuit diagram: . ..you have three battery related connections: Caravan Battery Car Charge Car Battery The Caravan Battery is obvious. The Car Battery is apparently a connection directly to your car battery so that, in emergencies, you can run the caravan electrics directly off the car battery. The Car Charge line assumes a charge supply (engine running) from your car and connects to both the leisure battery to charge and 'van electrics. So the short answer to your question is 'Yes, but. ..' But 1: you have to consider the albeit unlikely scenario where you are hooked up and engage the starter motor on your car. This will radically drop the car battery voltage and, without external protection, your zig unit output will also be used to start the car, which would undoubtedly blow fuses at best. In charge mode, this protection would normally be handled in the car towing electrics via a voltage sensitive relay that would only connect caravan to car when the engine is running i. e. 14. xV. You will need to make sure this is the case for you. You also need to make sure you're not switched to car mode when you're planning to start the engine. In car mode you also need to take care not to flatten your car battery! But 2: most modern systems just outright prevent you from connecting car to caravan battery in any way unless the engine is running and, when connected, disconnects all internal electrics via the habitation relay. I believe this is done to support towing legislation that you should not travel in the 'van whilst towing. You might need to check whether you're allowed to have 'van electrics powered up whilst towing.
  3. The output from the charger should be a 13. 8V float voltage, 12. xV indicates that the charger does not appear to be functioning. The test is to monitor the battery voltage with the charger tripped out, then turn it on, you should see a volt or so jump. If you do not see a jump, the charger is not functioning. Before writing it off though, check that the kettle plug hasn't come loose on the back of the charger. Also check the 'battery' fuse in the PDU and any fuses in the battery leads (in-line fuse). If all that fails, there is a guy on here that repairs charger units at reasonable rates.
  4. Have you searched the forum? I seem to remember a similar thread about removing these.
  5. Battery terminal voltage is only an analogy for state of charge, and in some cases, can be a very poor one e. g. after excessive sulphation. Even electrolyte specific gravity can be inaccurate and some batteries, of course, don't have an electrolyte you can easily test. The only true test for battery capacity is the C20 discharge test. I'll bet these batteries you are talking about that have returned to 12. 8V after many months will not delivery their rated C20 capacity. My current maintenance free car battery happily reports 12. 8V, and when discharged will run through a full charge cycle for many hours using my CTEK but crank it more that two or three times and it's dead. This will be due to corrosion, active material shedding, sulphation and probably even electrolyte loss - all the causes of battery aging. In the end, it might report 12. 8V and have 110AH on a label on the side but I doubt it would deliver 5. 5A for 20 hours, a better guess would be probably 3 making it in reality a 16. 5AH battery!
  6. @ericmark not completely sure what you are asking here, is your query whether or not it takes 3 weeks to properly charge a leisure battery? If so, I would say no. The rule of thumb is that VRLA batteries have about 85% charge efficiency so a 110AH would need around 126AH to replenish it from 0% SoC. How this is actually achieved depends very much on your your charging algorithm, battery 'age', state of charge, ambient temperature etc - you can't just apply 126A for one hour and be done! The biggest factors to consider when considering charging are battery chemistry and electrolyte temperature. Battery Chemistry Converting Lead Sulphate (PbSO4) into Lead (Pb) and Lead Oxide (PbO2) [discharged > charged] takes energy but it's not a linear reaction; the outer layers of PbSO4 are converted first, then the reaction goes deeper and deeper into the plates. You can achieve 80% charge in a relatively short space of time but getting the electrolyte deeper into the plates just physically takes more time. During this period maintaining a high constant current will increasingly be used for electrolysis of the water in the electrolyte and increasingly less for the actual battery charging reaction (PbSO4 > Pb + PbO2). This is why overcharging causes 'gassing' i. e. electrolysis of water to Hydrogen and Oxygen - a very explosive gas. To reduce this effect, a constant current is only used until the cell voltage reaches around 2. 4V (i. e. 14. 4V across 6 cells), after which the cell will exponentially increase the conversion of water to hydrogen and oxygen given a constant current. This voltage is then maintained, reducing the energy input by decreasing current. Once all the PbSO4 (or at least most) is converted, current requirements to maintain 14. 4V drops to negligible amounts. Then comes a balancing act - maintaining 14. 4V will ultimately lead to gassing and increasing corrosion of the exposed metal components so a good stage charger will then drop to a float voltage e. g. 2. 3V per cell or 13. 8V (or even down to 13. 2V on some chargers) to reduce this effect. In short, it's VRLA battery chemistry that determines the charging time - throw loads of energy in at first when the chemical reaction is easy, reduce the energy when the chemical reaction becomes harder . .. or risk explosion. Electrolyte Temperature The biggest consideration for how much energy you can throw into a battery is electrolyte temperature. As with all non-superconducting materials, flowing current creates heat via electrical resistance. The electrolyte is far from a perfect conductor so does generates heat, if the battery cannot dissipate this heat then the electrolyte temperature rises. This has two effects: the chemical reaction becomes less efficient and eventually the electrolyte will boil producing steam, which would increase the pressure within the battery container until it breaches (or the valve activates). Higher temperatures also increases corrosion. In conclusion, the time to charge a battery depends on how much energy you can throw at it without increasing electrolyte temperature beyond limits and how long it takes for the full chemical reaction to complete without causing too much electrolysis of the water in the electrolyte. The rule of thumb (i. e. balancing the effects described above) for most wet VRLA's is BULK charging (constant current) at C/10A (i. e. 10% of battery capacity in Amps, or 11A for a 110AH battery) then 5 x the BULK time in ABSORPTION (constant voltage). So a 110AH wet-cell battery at 50% SoC would require 63AH of energy at 85% charge efficiency, that's around 6 hours at 11A in BULK (63AH / 11A = 5. 7 hours), then 30 hours at 14. 4V in ABSORPTION. AGM batteries can take a C/5A charging current meaning the same full charge can be achieved in 3 hours BULK, 15 hours ABSORPTION. Obviously, the higher the state of charge when the charging cycle begins, the shorter both BULK and ABSORPTION stages need to be. So, no, it does not (should not) take 3 weeks to charge a leisure battery.
  7. Personally, I have all sorts plugged into my inverter from computers, through gadgets to washing machines . .. I would never trust a MSW inverter - way too inefficient (they get very hot) and creates all sorts of harmonics on the power supply. MSW inverters are fine for dumb stuff, electric heaters etc, but how many products are 'dumb' these days? I bought a very expensive inverter from Victron Energy (Multiplus) for two reasons: I trust their kit and I wanted the inverter integrated into my caravan's other systems (solar etc). It's rare that you need to power two power hungry devices at the same time, I would buy a good quality PSW (pure sine wave) to the spec of your highest wattage device with a two times surge rating. This is usually your microwave because even a low'ish power eg 800W actually draws 1300W in use and surges twice this on startup. I bought 1800W and this has coped with everything I've thrown at it. But with all that said and done and getting back to your OP, did you complete the troubleshooting by individually 'drop testing' your batteries? I noted the comment about 12. 7V being displayed but with three batteries in parallel you can't really trust this combined voltage reading. All three batteries should drop the same under the same load. Once this is done you can unequivocally state the inverter is the root cause of your problem.
  8. I'm guessing not because the machine functions, just doesn't complete the cycle. My coffee machine 'tethers' the heating element as it's pouring the coffee (ie turns the heating element on and off to maintain a set water temperature). I'll bet this rapid on/off is causing the problem. I figured the coffee machine itself would represent a reasonable 'drop test', but your point is valid. Just connect the inverter cables to one battery at a time. A 110AH battery will easily supply 100A, but the proof of the pudding is whether one does but another doesn't (hence faulty battery). If you see one battery dropping to 12. x V but another drops further (eg 11V) you have a battery failure.
  9. I would take care trusting any company that suggests a modified sine wave inverter is suitable for high tech electronics. This is off topic to your OP but sound general advice, imho. You only need to prove the batteries now before you can unequivocally identify the fault.
  10. Sorry, @michael pudney, can't offer any further advice without further info but my guess is your inverter is shot. Hope its not a Ring Automotive inverter, I had to replace three before I just asked for my money back.
  11. You can't be sure that everybody using that inverter (now or into the future) would know the cabling was underspecified. We will have to agree to disagree
  12. No, you must spec the cable to the inverter specs, not typical load.
  13. I have an 1800W inverter supplied from two 110AH batteries and it powers my 1200W coffee machine just fine. You have a higher power spec inverter and more battery capacity . .. meaning there is definitely something amiss here. You mentioned some devices need 2x 'surge' power, this is only for inductive loads, your coffee machine is NOT an inductive load. Examples of inductive loads are microwaves and big motors. AGMs do generally offer higher CCA (surge currents) than equivalent wet types but you have three in parallel so I doubt this is the issue. We need further info to diagnose this. Does the coffee machine actually work, that is, does it work on EHU? Does the coffee machine power up OK on inverted power ie is the inverter actually providing 230v? Do other mains devices work? What is the voltage at the battery terminals when the coffee machine is heating? With three fully charged batteriesbin parallel, you should not see volts drop below 12V. Could you try running the inverter off each individual battery? Maybe one battery has a failed cell that is dragging the whole bank down. A 3000W inverter could potentially draw 250A at 12V (3000W / 12V = 250A) meaning the DC cables to it would need to be at least 50mm2 cross sectional area and fused at no more than 345A. Check out here for further info on cable sizes. Any less would create a significant volt drop and be potentially dangerous. Good luck and do keep us posted.
  14. Ahhh, very interesting. The same author appears to have produced two different wiring diagrams for the same system. The one you linked to does indeed show a direct connection from the leisure battery to pin 9, however, on his website the following diagram appears: . ..which clearly shows the leisure battery connected via the habitation relay prior to connecting to pin 9 (note: the habitation relay is activated on the diagram above, meaning the tow car is connected). I've just checked the 13-pin plug on my 'van and there is no power on pin 9 so perhaps the version on his website is updated / corrected??
  15. There are literally hundreds of such products on the market, try Amazon and https://www. parkingcameras. com. I'm currently designing a parking / dashboard camera (for personal use) and I can tell you you can't even make them cheaper than they're being sold commercially.
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