Modina

@Kalahari CruiserThanks for the pointer to this comedy show. I had a quick look at their website.... I nearly fell of my chair laughing. Newsletter - Don't worries. We not spam ! I really like their payment policy/Terms & Conditions - they really make sense ! 😆🤣 ....and Mr Jamie van Wyk has an identical twin called Marius van Zyle.... I can't stop laughing.

@P1000 Thanks for sharing that link. That is very interesting and eye-popping. The no-load consumption of the Victrons seem substantially lower in comparison to high-frequency transformerless designs. (I measured my own 24V Axpert at 40W without even a fan or the LCD backlight running.) From that it can be concluded that a low power consumer, especially when off-grid, such as a boat, RV, tiny house, chalets, TV + laptop and lights user, etc. might gain using a Victron. Large power users that want to run a normal household using kettles, microwaves and washing machines would do better with SunSynk or other high frequency inverters. A toroidal transformer such as is used by Victron is about 50% smaller and lighter than an E-core transformer (thus also cheaper due to material savings), but I still would hate one of those inverters to fall on my foot. 😆

It goes beyond the cost of buying separate inverter, MPPTs, AC battery chargers, etc. I battled just to get lugs fit over my battery cables, and then they needed to be crimped.... You need all sorts of hardware (doohickeys 😁)and manpower to connect everything together and it opens the door to possible wiring errors. We all can have a blond moment occasionally.

95% of Lithium batteries are in metal enclosures. So that would mean batteries would also need to be earthed. I just checked on my Hubble AM4 and there is absolutely no provision made for that. Why is it that these regulations always sound as if they have been written by lawyers, rather than engineers? I wish they would include some more diagrams. I suppose that is left to some "author" that will interpret the words, make some diagrams and sell his book for R 2500. I do a lot of my own plumbing, including changing the underground pipes for new toilets, etc. So I brought this SA Plumbers Guide. It was a few years back and was about R2000. What a WASTE. I learned NOTHING from that book. Much about geyser installations but nothing on designing proper grey/black water drainage systems. Best to just follow common sense and logic and ignore the rest. This new world has anyway turned into a bunch of liars and cheats. It is easier to ask for forgiveness than for permission.

About Victron equipment - two things to note: 1. Victron does not keep spares for equipment older than 10 years. Not a problem for someone that repairs down to component level, but it seems repair centres are only repairing on a PCB exchange level. That would make equipment U/S. 2. Victron makes a lot of IP65 equipment that is 100% water proof, etc. This stuff is good for your yacht or bundu-bashing (for vibration), but it is throw-away equipment. These items are potted and totally unrepairable. Below is a link showing how people literally cut blue boxes open with a hacksaw or angle grinder, so as to replace a fuse. There are many other similar videos. These MPPTs are fully functional and only a fuse is blown, yet the whole damn thing needs to be thrown into the garbage.

I would think something like this: https://www.takealot.com/bennett-read-1000w-dribuddi-laundry-dryer/PLID46863506 1000W heater/blower fan The cheapest would be a clothing line in the SUN. 🤣

@jason compo you will not like what I am going to say now. In todays world, we should all become more independent and have a big drum of salt to be used for so called professional advice and opinions. For instance, I don't trust 99% of doctors anymore. The reasons are obvious - to some. However, there is a minimum of understanding that is ABSOLUTELY required to do any job. If you want to paint, you must at least know that you use water and not thinners to dilute your PVA paint, or clean the PVA paint brush. With regards to your panels, we are dealing with very simple, elementary circuits. High school science. We are talking about wiring and configuring a rather expensive system that involves DC voltages of 250V and maybe more, if you connect it wrong. 250VDC is more dangerous than 220VAC. If you, at this stage, still get confused, then I would SERIOUSLY RECOMMEND THAT YOU DO NOT ATTEMPT DOING THIS WORK YOURSELF. Rather get a knowledgeable person to configure and wire your system.

@jason compo I think it would have been better if you kept your fuse query under your Solar Panel Setup heading. In that other thread you mentioned that you have a total of 12 panels. So this is how you would connect to a single MPPT Note, I did not show any circuit breakers here. In practice one would add CBs to disconnect the one or other string.

From your pictures from your other post I see this: Your MPPT has an input range of 90 - 450VDC. 240VDC recommended input. Your panels have a nominal voltage of 41.5V (Vmp). So if you connect all 6 panels in series you will get 41.5x6 = 249VDC which would be perfect for your MPPT. From your other post I gather that you have a total of 12 panels? So make 2 strings of 6 panels each. Then connect the two strings in parallel. It might be good to fuse the two strings separately before paralleling. Separate strings need a 15 or 16A fuse. Once paralleled, you will have double the available current and will need a fuse double the rating, i.e. 30A as Nexuss mentioned.

That doesn't make sense. If you have 6 panels you should connect them all in series. Or make two strings of 3 panels each and then connect in parallel. You need to tell us what your inverter's solar charger as well as your solar panel specifications are. From that one can determine how the panels need to be connected without breaching your inverter's maximum input voltage. There is also a minimum voltage spec. You must make sure you work within those limits.

I have my Axpert 24V inverter (MPPT 3KW, 60-400VDC, 450Vmax) running for about 2 months now and need to think of getting some panels. I am looking at about 4 or 5 panels that would be mounted on a 3 degree pitched north facing IBR roof. Due to renovation and alterations, a part of the roof will be changed in future. The modifications will take place a bit further away, but it is a concern and I am still hesitant if I should indeed opt for panels now. (Renovations will be ongoing for at least another 2 years as I do most of it myself). Due to the installers overload, I am thinking of installing these panels myself. Can anyone point me to a supplier (preferably in the Cape) that sells an array of mounting hardware and some general guidelines to the available mounting systems and options to consider. Also, are there any recommendations as to what panels to buy, assuming availability. I just got a marketing email from Communica and they are now selling 600W Canadians. Here is the blurb: Canadian Solar Panel 600W 34.9V 17.20A OCV:41.3 SCC:18.47A Monocrystalline Module 2261x1134x35mm Weight 27.8kg @ R 4950 I prefer smaller panels (especially for a self installation) and I would also prefer higher voltage panels. For instance: Canadian Solar Panel 450W 41.1V 10.96A OCV:49.1V SCC:11.60A Monocrystalline Module 2108x1048x35mm Weight 24.9kg @ R3623 Any comments or advice on panel selection?

It's called moonshine. 😆 Your inverter's voltage and current sensing circuit might have a small DC offset. So the 1W you see is as a result of slight measuring error and/or ADC (analog-to-digital converter) quantization noise. I don't have any panels connected to my inverter and it too reports 1W solar input. Nothing to worry about.

If you use parallel strings, you at least need to make sure that all strings contain similar numbers of different panels. I have not had a look at the specifications of the panels you mention, but I think that one should try to match the nominal output current of panels as close as possible and worry less if the power and/or voltage is the same.

@turbochenAsk 10 people and you will get 10 different opinions. At the end you need to decide for yourself. Two points to consider: 1. I don't know about the Luxpower inverters, but be aware that many inverters reject generator power due to their unstable output frequency. Do not simply assume that you will be able to use your generator to top up the batteries. Once you have your inverter installed, test to see if you can charge the batteries from the genie. Also don't do a quick 1 minute test. Load your generator with something like a kettle and switch it on and off. See if battery charging is maintained as the genie's AVR battles with the load variation and the genie's speed hunts and wobbles. 2. Should the grid collapse completely the diesel and petrol supplies will likely run out in a few days. In fact most things will stop and crash. Water, sewage, communications, food supplies, etc. In such a scenario I would rather huddle at home than to go out into the streets trying to buy fuel.

Ferro resonance one would worry about if you plug induction hobs or inverter welders and similar loads to the output of your inverter with thick, short cable. Luckily an inverter installation (normally) sees many, many meters of house wire between itself and any serious inductive loads. So the interconnect resistance should dampen the system.

The short answer is no. These power supplies are small and easy loads. Home alarm systems normally use a conventional mains transformer with an output of 16VAC and rated for about 30 to 40W. The alarm then has a simple rectifier circuit and a LM317 linear regulator to create the 13.85V float-charge voltage for a 12V 7Ah SLA battery. Some better, or more modern, alarm panels might use a small switching buck regulator instead of the LM317. It's odd that you would suspect the alarm PSU. What gives you that suspicion?

The intended use is to power an inverter with a few 220VAC items inside the camper. So I read that as possibly already having ownership of an inverter. Nobody here touched on the vibration issue. Do you agree with my point regarding Lithiums and their much better suitability in such an environment, in general? It would be helpful to at least know the required battery voltage. Seeing that SunSynk was mentioned, I presume it must be for a fairly large system running on 48V. I am now also going to venture beyond the battery. I personally would be much more concerned that the inverter can handle the vibration. My own Axpert inverter has a control PCB that is on a 0.8mm PCB substrate. Normally PCBs are 1.6mm thick. I don't know why on earth one would make the control PCB so thin. It's not a cost issue. Anyway, an Axpert inverter like mine would NOT, guaranteed NOT, survive constant vibrations. I would go as far to say that all the hybrid inverters that we mention on this group are fixed use only and are not made to be lugged around on mobile jigs. They might be OK for a tiny house being moved occasionally. But we don't do that sort of thing in SA anyway. For Bundu Bashing, the go to inverters would be Victron. 2nd option would be a very good quality inverter in those Aluminium extrusion profiles. You do not want any equipment that has a number of PCBs mounted at right angles with connectors between them. I spend many years in the defence sector and I often had equipment environmental tested - vibration & shock, heat, humidity, salt-spray, radiation, etc.

Well @Steve87 perhaps you can donate one or two dead SunSynk Inverters to @BritishRacingGreen so that he can open them and get acquainted.... Hopefully he will not strip out the IGBTs and MOSFETs to use in his Axpert repairs. 😂

Gee guys, you are running away with this. @Gandalf was only asking about a Lithium battery that is able to take vibrations. Maybe his bundu bashing friend already has an inverter. Now you offer him plastic integrated inverter boxes with handles (put there for easy disposal when it dies) and batteries nobody has seen or knows where to buy replacements. You are putting a lot of words into his mouth. 🤣 Or is it the cart in front of the horse. @Gandalf I am an idiot when it comes to batteries.... Lead Acids have a terrible time with heat and vibration. They contain heavy plates and the mountings of these can crack and fail under vibration. Lithium batteries are firstly much lighter. But the way I understand it, they are made from a few layers of polymer sheets that are rolled up into a cylinder. See this link: So I think a Lithium battery's construction is inherently vibration tolerant. Just make sure they stand in the way the manufacturer envisioned. Don't mount them upside down or upright when no provision is made for such mounting. As to fridges, 24/7 charging, cranking current and what sort of inverter to use, you haven't asked, so I will not comment. 😐

@Scorp007 You can't judge them by their looks. They all look very similar but made by different Chinese manufacturers. The bad ones will use underrated switching transistors, Schottky diodes, smaller magnetic cores with thinner enameled copper wire, etc. yet appear similar to the better quality units. Ah, Microrobotics. I need to have a look what they stock. Thanks.

I am considering designing a 230VAC + MPPT battery charger for a 12V system. I would base the MPPT on this opensource design: //www.youtube.com/embed/ShXNJM6uHLM?enablejsapi=1&origin=https://www.instructables.com Design a single PCB to take everything and mount it in one of these alarm panel enclosures that are readily available. But it's more of a dream at the moment. My house renovations are far behind and I just don't have the time for such a project at the moment.

@Scorp007 Where should I start? I looked at these type of supplies for months. You get them for various output voltages and power ratings from about 15W to 600W and beyond. You can buy MeanWell power supplies arny time. They are reliable and well made. They are also very expensive. There are some cheap ones on Takealot and they just seem to suck big time. I ordered a small 12V 50W from them and at first switch-on I was greeted with a loud bang. I opened the thing up and found a number of devices where blown. The PWM chip doesn't even have markings on it. I also spend some time at ACDC opening their boxes and peered through the ventilation slots to look inside. The ACDC units are NOT cheap. Yet some of them don't even have an input filter. I can accept it if a 30W doesn't have an filter, but I saw one of their higher powered units also without a filter. Now that is unforgivable. It is for that reason that I cannot trust their products. If the manufacture skips on the filter, he will cut other corners as well. All these supplies have a preset potentiometer to adjust the output voltage but the range is not far enough for 12V or 24V battery charging. Ideally you want a 15V/30V supply, and these are available overseas but not from places like Takealot, ACDC or Communica. The output voltage doesn't worry me too much. Its a schlep, but one could remove the transformer and change the turns ratio on the secondary and then make it whatever you want. One could also change the feedback resistor(s) to give wider output voltage adjustment, but one should not overdo so. a few high quality supplies have a current limiting potentiometer as well. @BritishRacingGreen concern is 100% valid. The normal supplies will shut down at over-current. However this is a safety feature and not something you should use on a regular basis. Sooner or later you will blow up the supply. You definitely need current limitation/regulation. Again, this can be implemented with a small add-on circuit. These sort of modifications are just a challenge to implement neatly. I don't like a wire mess with little PCBs glued with hot glue or double sided tape. 🙄 The next step one could consider would be to add a small 8-bit micro to implement a proper Lithium charging algorithm with charging shutdown and automatic re-starting when the voltage drops below a set value. I would keep the PWM chip to do its thing, and the micro would only close the low-bandwidth voltage/current control loop. Another route to cheap hardware is to use a ATX power supply from an old PC. These supplies have over-voltage monitor circuits and the like, but it would be more work to modify these. ATX supplies are normally very reliable, but then again they are not run at high load for long stretches of time. 20A for 12V battery charging is no problem. For 24V batteries one would need powerful ATX supplies such as used in gaming PCs. Those are scarce and expensive. @Scorp007 where do you source these Hytronic supplies?

@Scorp007 Where do you buy your R 1500 MPPTs? For R 1500 you can't even buy a decent 12V 8A lead acid battery charger. I know that Victron is top end stuff, but they seem to go up in stages of current and in stages of voltages. I am sure that many of Victron's MPPTs and other equipment such as inverters are of a common design and often will use the same PCB with just slightly beefier MOSFETS to take higher current / voltage. Then charge R1500 more, just because it can handle 10A more, yet basically is the same. I have seen other manufacturers follow similar trends, albeit at lower prices than the Blue boxes. If you consider the above, you really do realize what you mentioned earlier in a different post. Axpert inverters are excellent value for money, considering all the stuff crammed into those boxes.

@BruceL I know you where happy to at least get your unit repaired, but I wish that repair centres would perform proper debugging and component level repairs rather than simply replacing PCBs. @RustyGate If your inverter runs in battery mode, it means that the DC/DC boost converter as well as the DC/AC inverter are still working. This is good news as there are many high current and high voltage MOSFETs in those two sections that would be rather expensive to replace. These components can also be a challenge to source. I predict mountains and mountains of dead and sometimes still alive equipment that will fill South African garbage sites in the not too distant future. Simply because there are not enough people that can service this stuff. Not to mention people that due to finger trouble, come to the wrong conclusion that the equipment is dead. This will be especially true for the sub 2KVA cheaper entry level systems that often still use lead acid batteries. The vultures at the disposal sites will hack out large inductors for a few cents worth of copper. Leaving the true value to rot and poison the ground. What a waste. I would also hope that Shabier (is he still around?) from Communica or some of the other electronic component suppliers realise this situation and pre-emptively start to stock items such as MOSFETs, IGBTs and large electrolytic capacitors. This would be a huge saving from always having to order through mail-order from overseas. Communica has fantastic turn-around times on orders, often under 24 hours. Sadly, they seem to have completely moved away from keeping a decent range of electronic components.

Thanks guys for your feedback. @Scorp007 Yes I would connect a battery and yes, using an Axpert would be the cheapest way of charging a battery. That is why I am interested in this. Lithium mains powered battery chargers are also very rare animals, if you require 15+ Amps. Also, there is less clutter. It is all integrated in a single box. I disagree with your 25W for a 24V Axpert. My own 24V Axpert quotes a power dissipation of <35W, but I have measured it at about 40W. That is even without the fans in operation and the LED backlight switched off. There is nothing wrong with using the inverter as well - during times one needs 230V, but not as a UPS that runs 24/7. My personal ideal would still be to have a small hardware circuit that measures the line impedance on the 230V output bus and then wakes up the inverter when the impedance drops. In other words, if you plug a mains consumer into a wall-plug and switch it on, the inverter would be woken by the circuit. This would be specially useful for small places such as off-grid cottages, holiday homes, tiny houses, RVs and such.