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  1. Yesterday
  2. The Terrible Triplett

    Infini Plus 3Ph 10KW Neutral wire bond/Join with Grid Neutral?

    For clarification: No Eskom to the inverter, totally off-grid, and no charger either. Pure inverter. Far as the manual goes, it says connect the casing, as we are discussing. I know for a deadly fact not to bring anything DB board related, close to the N of the inverters output. I don't do that anymore. To date no-one can tell me with absolute clarity and / or conviction, what is best. Here is what is: Had a 4mm wire earth connected to the DB board's earth connection, by electrician, but he had doubts. +-6m distance. The DB boards earth is connected to the actual earth rod sticking out of the concrete slab in the braairoom. +-2m distance. Gets more interesting: My Interlock gets power from inverter and Eskom. Eskom side of the Interlock is plugged into a wall socket using a 3 point plug with L/N/E connected via the plug, to the DB. And I know the trips inside the box works. :-) 5 electricians I asked over time where at a "loss" (pun intended) of what is best. DB or earth rod ... is it safe for the equipment, humans ... me? Keeping away from the DB, as there are neutrals in there: Connect the Inverter casing direct to the earth rod, even though the DB's earth is also on it? Remember, I have a various Doctoral degrees and diplomas on how to blow things up.
  3. The following is cut from the Victron Multiplus User guide; "The MultiPlus is a safety class I product (supplied with a ground terminal for safety purposes). Its AC input and/or output terminals and/or grounding point on the outside of the product must be provided with an uninterruptible grounding point for safety purposes"
  4. I cant think of a situation where earthing a metallic housing of an electrical appliance wouldn't be acceptable - in fact if it has grid power anywhere near it then it is a requirement, and if it doesn't then you should do it anyway.
  5. Again, I'm not an expert, but this is my understanding. If you have Neutral bonded to earth and you have a low impedance earth back to the source, then if an earthed surface ever becomes live it will almost certainly lead to big sparks and lots of current flowing, or in the usual lingo: It will create a large fault current. In such networks a simple over-current breaker provides the bulk of the protection, and the RCD is really just for extra safety (which you will obviously not skimp on when your family is at stake, but you might in another setting where other things are more important). With other earthing types, where the earth loop has a high impedance, you cannot rely on a large fault current to disconnect things, so the RCD (which looks at an imbalance) becomes mandatory. If you think about how that might work: Suppose your neutral is unbonded, so the two wires float somewhere between 0 and 230VAC (probably around 115V). If any one of these wires (live or neutral) were to come into contact with a human, the potential difference will cause current to flow through that human to ground, causing an imbalance and tripping the RCD. So it sort of relies on the basic idea that voltages below 60V will likely not kill you, and voltages above that will likely only kill you if enough current actually flows. So it is less safe, most definitely, but still considerably more safe than no RCD at all.
  6. pilotfish

    MECER AXPERT SOL-I-AX-5M Settings Help

    Hi Anton Go to the download section of the forum and grab [Axpert Settings] by @Chris Hobson Then read the attached document and update your firmware. NOTE: I think the latest version of the Aussie firmware for your equipment is dsp_LC1_73.00b which is also attached, but using this IS AT YOUR OWN RISK!!! Then get a BMV-702 battery monitor because ICC does wonders for the Axpert in conjunction with the BMV-702, but is relying on poor information without it. Lastly I think your peak solar generation of 2.6kW is cause for concern (if it is really your peak) - I have a similar setup with 2 Axperts and 6200Wp, my peak generation today was 4.389kW (hopefully it will start ramping up now considering today was winter solstice). I think you may need to look at your panel setup. Coulomb Latest Patch Description.docx dsp_LC1_73.00b.zip
  7. I'm not sure, but that is what I have done. There are some that say all earths must be equipotential and connected together. If your grid connection is TN-S and you're not allowed to make a second earth at the premises (aka PME), you really have no choice. And my excuse is that a qualified electrician installed it that way. There is however something in the rules somewhere that says it should remain safe, or more specifically that things such as your RCD must continue to work correctly, even if you lose the earth from the transformer. You could do this by having a good local earth spike and connecting the case to that. That means that while in invert mode you always have your own local earth. So my gut feeling is that both ways are acceptable, but since I'm not an electrician I cannot say precisely. Both of them are certainly safe, the former just has the slight risk of a broken earth. With a broken earth you still have RCD protection, it's just not as sensitive because the earth fault loop impedance is high. You essentially have an IT-system. It is possible that it actually complies with the rule that things should continue to work. I don't know :-)
  8. The Terrible Triplett

    MECER AXPERT SOL-I-AX-5M Settings Help

    One question: Do you have a Victron BMV?
  9. The Terrible Triplett

    Infini Plus 3Ph 10KW Neutral wire bond/Join with Grid Neutral?

    If one where to connect the Victron inverter casing to the earth in the DB board, would that be acceptable?
  10. I hate this term. They still have a transformer, they can just get away with a much smaller component and use a different material (eg Ferrite, so no eddy current issues in the core) because of the higher frequency. Basically, if you study the various conversion topologies, there are a few low-power designs that use only capacitors (also called charge pumps), but they are generally good for generating a high voltage supply to drive FETs at most. For anything that can do any level of power, you'll want to use some kind of magnetic component, some kind of inductor. Now there are numerous such converters, buck, boost, sepic, cuk, and they all use some kind of magnetic component, and almost always there is an equivalent isolated version that essentially uses a secondary winding on the inductor: aka a Transformer. So anyone talking about it being "transformerless" must be in marketing. They are also the idiots who think the inverters with bigger transformers (MLT, Victron) are old tech... the truth is these inverters use toroidal transformers for better efficiency. Zero problems. Designed in in fact. It has a bonding relay. When the power goes out, it bonds the neutral to the case of the inverter. All you have to do is ground the inverter case to a suitable earth. For example, on a boat/barge/yacht it would be grounded to the hull while in inverter mode, but it would use the shore earth when on the grid. When you install it in the city, you simply earth the case of the inverter and you're done.
  11. With an approved gridtie inverter connected to the Solar-Log 50 Gateway and PRO380 Meter you can do grid limiting or preventing excess energy feed back into the Grid. Although I am not in Cape Town you are welcome to give me a call and help you if possible with advice. 0828935316
  12. antondeswardt

    MECER AXPERT SOL-I-AX-5M Settings Help

    Hello All I have 2 x AXPERT Model: SOL-I-AX-5M Inverters in parallel. I have 12 Panels connected to each Inverter, so it is suppose to be ± 3kWp each Then I have 16 x 260Ah 12V AGM SonX (Ritar) Batteries I have the Rasberry pi with ICC Software Version 2.3.9 Where can I find the correct settings. The problem is that my Batteries don't last and my Solar generate a maximum of 2.6kWp during this time of the year. I will appreciate some help
  13. plonkster

    Infinisolar not reading PylonTech SOC

    35 is fine if each inverter has it's own pair to the busbars. 4kw at 48V is less than 100A. You can get away with 25mm^2 in a pinch. Of course if any part of the current path is shared, then you got to beef that bit up.
  14. It's 3.5KW for single phase, so I'd expect it to be around 10 for 3-phase. You are allowed to fit a larger array or a larger inverter as long as the inverter is configured to not feed in more than the legal limit. It helps if it is on the list, and many installers won't touch it if it isn't on the list, but the list is more of a guideline, a resource that helps you select something that will sign off. The Victron inverters for example (the older ones, before the MultiGrid came along) has NRS097-2-1 compliance if they are paired with a Ziehl anti-islanding device, and the Ziehl is on the list on its own too, so you generally can get it signed off, though it takes more work: It is not on the list so some won't touch it. I'm also told that it isn't really policed, so there are people who fit one unit and later upgrade to something else. Of course I'm supposed to tell you not to do that.
  15. Youda

    Infinisolar not reading PylonTech SOC

    I've just read the whole thread and I have to agree with what most of the guys are pointing to. My 2 cents: 1) 35mm2 cable for 3x InfiniSolar 4K is way too small. Use 50mm2 for all the connections. 2) Also, check the voltage drop on DC fuses, while under heavy load. 3) 2.5m cable between (small) battery pack and array of 3 inverters is too long. Build a shortest possible battery connection and keep in mind that all the inverters must have the same length of cable between the battery and inverter itself. This is explicitly noted in the manual for parallel operation. 4) Lower the cut-off voltage setting in the Infini settings, don't forget to SYNC. 5) Measure the battery voltage and compare that with what inverters are reporting. If there's a difference in readings, you can calibrate the InfiniSolar's ADC in the same way like Axpert. The link bellow is for 3K version, which is different from 4K. For 4K ask your dealer for "battery calibration SOP". http://www.ostrovni-elektrarny.cz/support/Voltronic/AccessPort_and_SOP_battery_calibration.rar
  16. Gnome, Path to the ground - yes, and it's not just the buck converter. There's a lot of other circuits in the inverter (just like plonkster mentioned in his previous post) that may cause troubles when you ground them (or connect to N). Speaking of transformers, high-efficiency inverters tend to avoid them as much as possible, because they are hindering the efficiency and rising the cost of device. Therefore, without knowing what's that particural inverter's topology (or architecture), you cannot be sure that there's galvanic isolation between the components. Two main topologies ale Low Frequency with Transformers and High Frequency transformerless. For a shame, both can be manufactured as non-isolated, so this won't help you much. Even in the devices where there's galvanic isolation between the battery and the high-voltage bus, there's no galvanic isolation between the grid-in and inverter-out. Just imagine how big chunk of metal is a 10KW 3P transformer.... So, whenever you want to bond N-in and N-out, you have to check the device capabilities first. That's why some PV installers say that it's okay, while others are strongly against. @plonkster, by the way, how about Victron and neutrals bonding?
  17. shanghailoz

    Mistake 2 - Battery/Invertor mismatch

    No dead acid. Lithium (LFP). Its cheap enough now not to bother with the pain that is Lead Acid, far simpler too imho.
  18. I should add a proper answer for Big Foot though. In order to legally feedback, you will need to register for SSEG with Cape Town. I also have a 3 phase system solar, although mine doesn't feedback to grid. Last I checked, 3 phase is limited to a 3kw system for SSEG - may have changed since I last looked in 2013 though, so ask. You will need an engineer signoff for your system (min 20k or so), plus do the paperwork. Your inverter will also need to be listed in their approved inverter list - if it has NRS certification (NRS 097-2-1) , it will typically be listed. I have an example of that paperwork on goingsolar.co.za, newer lists of approved hardware should be findable on the much improved CoCT website. If not, suggest email Ryno or Brian @ CoCT and ask for the list they can be contacted on - Ryno.vanderRiet at capetown.gov.za Brian.Jones at capetown.gov.za Ryno is generally helpful. An overview of stuff here - http://goingsolar.co.za/solar-grid-tie-legalities-in-cape-town-south-africa/ Feel free to ask me more questions, I have looked at the process, although decided against it, as it wasn't economical for me. I basically said nah, and went offgrid.
  19. It depends entirely on the topology used, and whether the designer thought it best to reference all things to a common place. The long and short of it is don't make assumptions :-)
  20. They're trying to do that in Observatory, Cape Town also, I've told them to go jump currently; Well, actually, I generally ignore them, and don't let a meter reader onto the property at the best of times. All readings go via photo / email, or at least did, I haven't been there in > year due to health reasons. Note to self, don't break your hip skateboarding
  21. I don't really see how this is possible. In inverter mode it is boosting the voltage to 400v DC, rectifying then run it through an H-bridge. The boost converter is being driven through a transformer so I don't really see how the battery is connected to the circuit. Your diagram only contains the inverter stage but I don't understand how you see that being connected to ground? Are you saying that the buck converter is somehow always creating a path to ground? How? You can't just feed the 240v AC back into the battery, you either need a buck converter or you need to feed it back through that boost converter transformer. Are you saying that buck converter is not galvanically isolated? (I can't imagine that being legal)
  22. The Terrible Triplett

    digital thermometer placing

    On my old Morningstar I had a temp sensor, which was aimed towards adjusting the charging algorithm, based on ambient and 1 battery pole temp. I think the Victron controllers takes the ambient temp, and adjust accordingly. So now I am thinking, once I start worrying about temp on a batt, by then it is too late, the batt is a gonner, last leg, and all that.
  23. Chris Hobson

    digital thermometer placing

    I stuck mine on the middle (top) of the polyurethane case with prestik and although I did use the values to adjust charging regime I was more interested in any temperature variation in the batteries. I thought I would pick up any impending disasters. In the end (probably one of Plonky's pet peeve phrases ) it was the BMV rather than temperature that heralded my battery banks's demise.
  24. SilverNodashi

    Infinisolar not reading PylonTech SOC

    So, revisiting this issue. At another installation, with 3x new 5KW Axpert inverters, each with 2x Pylontech batteries, the inverters run quite long (depending on the load) and drained the batteries to 80% SOC until theuy shut down Yet, the 3x Infinisolar Inverters run for about 7 minutes and then shut down. The screens were completely off. Yet, on the batteries, all the LED's are still lit. The inverters shut off at 48.3V / 29% SOC. Could it really be a case of the ADC not reading the Volt, or Ampere of the batteries properly? Would a firmware update fix this, if one is available?
  25. pilotfish

    digital thermometer placing

    I have had a cheapie lying around for a while so I took it now and measured boiling water through the transparent glass kettle, which in Joburg will be around 96C. My results varied from 85C to 56C depending on the measuring angle (85C when square on).
  26. plonkster

    digital thermometer placing

    I'm not always sure if they do as well on surfaces other than human skin. The one we have (which is notoriously inaccurate even for its intended purpose!) has two settings, one for human skin and another for other objects. This alone leads me to believe your results with this rather expensive meter is going to be disappointing. In fact, I'm thinking of getting a nice industrial one for maybe double the money shown here... and using it on my kids too. 50 bucks says it will do better that way round than the cheap pharmacy model.
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