Fundamentals Of Electricity

Hi, I've had a Victron system since 2023 and it's mostly given me no problems. In Dec, I had an issue that resulted in the MultiPlus-II being sent for RMA and the PCB was replaced. Since receiving the MP back, I've been having issues with the Earth Leaking tripping whenever the grid goes off or comes back in which unfortunately is rather frequently in my neighborhood. This is obviously very frustrating since I constantly have to reset the Earth Leakage and all my devices and appliances are suffering. Any ideas what might be the cause?

Recently Goodwe SA were looking at my inverter (at my request). They tweaked some settings, and they also called me and asked me to check the CT coil. I declined. I am know enough to know that I don't want to be putting my fingers inside the DB, and even less to be moving things around in there. No. Not a good idea. Anyway, they said that my inverter is feeding back into the grid, despite the appropriate parameter being set to not export at all. I knew about this. As with other things on my PV journey I've accepted that things are just like that. I don't think the export per day is very high, and overall the systems imports more from grid (also a bit every day) than it e…

Hello everyone, Looking for some input from the electricians on the forum, mostly to make sure that the aircon installer does not take shortcuts and what not. I am looking to install 4 split unit aircons (all 12000BTU), placing the outside units in a single open location on a wall outside. What are the rules (SANS) for wiring theseinto the main DB? I understand that these are all supposed to have dedicated breakers of 25-ish A in the main db, with a isolator for each unit fairly close (1m?) from the outdoor unit. Outside isolator to be 2P swithcing both neutral and live. BUT, instead of running 4x cables and having 4x breakers in my main db, can I instead run a single 10…

Good day. Hope every one is well today. I'm asking for a friend. About 2 weeks ago power went off due to vandalism. (from Witbank all along the old road to Middelburg) Power was off for about 2 days and it was very overcast. My friends battery switched off due to low voltage. (SHOTO SDA10-48100l5) On a Mecer 5kva inverter, 2x 600w bifacial panels in series. (Ground mount) When grid power was restored, The inverter was off and the bypass to grid was on. All appliances worked fine. The bypass was switched to inverter and the system was powered on. About 10 seconds after the inverter was started, it went BANG!!! and all was off. Before this the system was working fine for 2 …

I have two parallel 26V Lithium batteries on a 3kV invertor and 83V from panels to the combiner box. The 30A fuses on the combiner bow keep blowing after a short period of charging. What could be wrong?

I currently have a small house/hobbyhouse, and my off-grid Victron system is in a small room that is attached to the house. I need to add some much needed lighting to the house, seeing though its a hobby house i was considering covering the ceiling with those small spotlights, then i got to think ... those are DC, and the inverters do have losses converting AC to DC, ... also ... almost any hobby device uses DC but gets converted by the power supply from AC. Could i not have a small DC distribution board to power these things directly? It all sounds fine .. but i am not sure how to handle limiting current, voltage etc. Is this even a worth while exercise? How would a …

Where I live, folks are complaining about non-trivial increases in electricity billing and metered usage. This predates the tariff changes which only kicked in on the 1st of this month. Lots of people are complaining about this, so I don't think it is a few folks who have only recently started analysing their municipal statements. A parallel complaint is that grid voltage is low. I sometimes see 210ish late at night, but often we drop down into the 190s during the day (this happened today). On restoration after a load shed it can often drop down into the 180s. Last night it was in the 170s for a short while. Might these two things have something to do with each …

Good day First off I am not an installer, nor competent on solar in any form or shape - so please excuse any nonsensical remarks or questions. So the background as follows: I have 2 x 5kw Deye inverters, setup as slave and master Both were set before to draw 10W from grid at all times This worked out to be around 30 w of continuous usage if the need for higher consumption from grid was not there The master got damaged and replaced and since then: With the settings as before on 10W for both machines it now continuously draws around 300W, when no Eskom load is needed I have changed this to 0W, 30W, 50W - it mak…

Hi everyone, I have a few questions on 3 phase power in SA. I couldn't find any straight answers on google. 1. Why do the loads on a 3 phase power system need to be "balanced". Is this only to avoid tripping/overloading any single phase? 2. Does balance mean, at any given time, the loads are at somewhat equal power draw across all 3 loads? Or does it simply mean that each phase does not exceed a certain power draw, and certain phases can remain idling? For example, I have geysers and aircons on phase 2 and 3, and all my main plugs, lights, appliances etc on phase 1. Phase 1 is going to in use 90% of the time, as the geysers operate on timers, and aircons ar…

I have just returned from an assessment as a second opinion from a client where his insurance claim for damaged infrastructure was rejected. The damage was caused by hot connection inside the db from the neutral on the main incoming 16mm² cable that got so hot it combusted setting fire to the ceiling in the corridor. Remember the RCD can not detect a hot connection until the earth and neutral conductors melt together only then will the Rcd react.(Rcd mainswitch in db) All safety switchgear was installed correctly. The insurance assessor was sent out and the claim was rejected not for the actual cause of incident but because a non compliant generator was wired to the db bo…

Hallo Gents, Can someone enlighten me on this issue, I have a plug tester showing correct plug wiring and correct earthing. When there is power 3 lights are on and all good. But when there is load shedding or I turn off my main feed the earth leakage light goes out. I do this test on a plug that is coming from a solar inverter that is wired into the db’s earth and neutral and live going through a cb. Where do I start looking? Thanks! Dion

I have 6x 550w Longi panels that have been doing duty since 2023 in 2 MPPT strings of 3 panels. They are combined at a single DC surge protector before being fed into the inverter. This works nicely since the Luxpowertek SNA5000 specs state PV Array MPPT Voltage Range 120Vdc~385Vdc with a start voltage of 110Vdc. Now I am thinking of upgrading to the LXP 6000, but it has an MPPT start voltage of 140Vdc. The panels being around 40Vdc typically output 120Vdc~139Vdc. Thus, they will have to go in series, but where is the best place to do this? Before the fuse or after the fuse? Current combiner setup below, solar coming in from the top, passing through the fuse, then to t…

Inverter s out there are 3 cables N L and PE. I ve put all those MCB as seen on picture. Is it ok or i should just use L for mcb and others just use wago? Thnx

I have just moved to a house and am in the process of finding out which switch activates what. There is a separate toilet and bathroom with a double wall switch for the lights. The one switch turns on both lights, the other does nothing. I opened the switch to see if the non active switch was wired, suspecting that at some time perhaps an extractor fan may have been connected to it. It had a 2.5mm wire attached as opposed to the 1.5mm on the active switch, judging by noticable diameter difference with all the other wiring. I measured the voltage from earth (metal of 2x4 wall box) to the open side of the switch and registered 42V , I dropped the breaker for the circuit at …

Good evening, my landlord recently installed prepaid meters into the 3 freestanding homes on the property. My place has 2 db boards (seems my home is split in half). I also have 2 geysers (first query) the main geyser does not switch off at all, and the second geyser only goes off if you put both geyser switches off (at db board)... Second query - the other tenant loads electricity as do I, but if my mains trip he also goes off... if I run out of electricity he goes off with me, even if he has ample units. If his db trips then I go off, but if he runs out of units, then I'm not affected... When the meters were installed last year, I was loading 1200-1500, by Dec/Jan it ju…

Howzit guys so I'm in the process to go completely off grid soon now my question is earthing related. does the N/E Still need to be Bonded together if there is an Earth rod installed? and if so if it has to be bonded together still the earth rod? does it need to be connected to the common earth bus bar as well? the idea is to not use Grid Ever again (Eskom Comes and disconnects the line going to my house ) just solar/generator have way too many problems with grid to either die for a few days or to just supply 80 - 110v >.>

Good day Let me start off by saying I have a workaround for this issue, but surely it must be a glitch? Not that I am at all qualified in the field of PV, so my comments and deductions might be silly to the experts on this forum. In my limited technical understanding the setup of my solar system is as follows. 20x455w panels 2x5kw Deye inverters 5x5kw Greenrich batteries Setup to feed house 100% at all times - so nothing in the house excluded from getting electricity off the inverters. Only when battery and PV can't supply demand if would use Eskom My system is big enough to take me off grid about 85% of the time, which means my batteries are fully charged through the…

Hi everyone I'm currently in the process of going off grid. I have a few concerns about the earthing and the earth/neutral bond. My panels are earthed directly to a copper earth rod in the ground. 1) Can I still use Eskom's earthing rod going into my DB as this earth is still the best you will get? If not, what must I do? Currently all my ac earths are connected to earth rod in main DB. 2)Can I feed a 6mm wire from main DB earth rod to my inverter? 3) Where and how will I do my permanent earth/neutral bond once the prepaid meter is removed and fuses pulled from mini sub? Oh! Please try and explain in away that a stupid diy guy lime myself can understand.

Good afternoon. I just bought this Lumo 2.5kW UPS that I was recommended. I wanted to connect it to my DB board but I am wondering if I need to earth the metal case of the UPS when I connect it? Please could some one explain if i need to or not. Thank you!

I know this sounds stupid but how does any normal house not draw more than 60A at times? I've worked out that in my new home if I run my oven, both geysers and my two ACs together that already 65A. I know this won't happen often but that's just 5 items. That's not everything else that just runs all the time. If I install a 16KW inverter will it allow to draw max between batteries and Eskom?

I know the reg says AC and DC may not be mixed. Can I route from a DC db through an AC db and then into trunking. The DC wires will be inside a conduit/Sprague pipe. The DC and AC db's are directly next to each other. Thank you

Excuse me if my terminology is off, I don't have much knowledge about electrical work. Almost 3 years ago I purchased a property which was sectionalised by the developer I bought it from. It is one erf sectionalised into two sections each with it's own home. My section holds the original home and the second section holds a newly developed house. After I had been staying there for a few months the developer completed and sold the second section. They applied for the electricity connection with Eskom but apparently it takes a while so they asked to connect the next door house to the main distribution board located in my house by laying some pipes through the roof …

Good day All Last night I read the "wiring-unlimited" e-book shared on this forum. Wow! Excellent read. I would, however, like to ask for some clarification. On Page 49 they talk about the different types of distribution networks namely, TN-S, TN-C, TN-C-S, TT and IT. (Where-from the letters?) In any case, what kind of network does South Africa use or does it depend? I, erroneously, always assumed the three wires on overhead transmission lines were Earth, Neutral en Live. I assume they were actually Live Phase1, -2, and -3 and that the Neutral and Earth only come into "being" at the property? What network does my house have if, as far as I can tell, a single,…

Broken neutral conditions on low voltage 3-phase 4-wire networks present a challenge not just in terms of appliance failures but more importantly exposes the possibility of life-threatening contact incidents. The Earth Leakage Circuit Breaker (ELCB), required under South Africa law, is purposely designed and installed in all household distribution boxes to mitigate for earth fault conditions associated with these appliance failures and possible contact incidents. Due to limitations in the ELCB design, the unit fails to operate under broken neutral conditions and thus renders the system dangerous and unsafe. A new bespoke Broken Neutral Safety Device has been developed to …

Hello I have built a data acquisition system for my Mecer solar/grid inverter. Everything is working and I am getting data into my repository but I don't really know what I'm looking at as my background is coding, not electricity. Could someone please explain what these figures are that I'm getting back from the system? Some of them are self explanatory but I have included all the data types returned for completeness if someone else comes across this post looking for the same information. Here is an example of a reading coming in every minute: AC Active Power: 0161 AC Output Apparent Power: 0162 AC Output Frequency: 49.9 AC Output Voltage: 232.0 Battery…