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This is a tricky question due to CoC inspectors, if the main DB has earth and neutral bonded, (NRS97-2-1 specifies this as compulsory for certain configurations), only live is required for the SPD because Neutral is already connected to earth, but if it does not have the PEN bonding then live and neutral (L+N) should both be protected by the SPD because of the distance to the local transformer, your average CoC inspector is going to say that both are required, so it is the path of least resistance to just install L+N in all cases, that way you don't have to have the bonding discussion with the CoC inspector. The same applies to earth spikes, desired vs compulsory as per NRS97-2-1 will likely become compulsory in all cases when a CoC is performed, so again the path of least resistance is to install the earth spike in every case which brings us back to the required cross sectional area of the earth spike earth wire that must connect to the Eskom Earth which is a different requirement to the solar panel earth wire

The regulations are very clear, and the issue of creating a potential between 2 earths is very clear, do NOT do it. There is Only one earth ! Repeat after me ! There is Only one earth Lightening Protection System regulations and Solar Panel Grounding Regulations are completely different things, solar panels are not grounded for lightening protection and a 6mm square area wire is not up to the job of lightening protection which requires very large area down conductors 50mm square = 8mm diameter (here is where you all get confused, you see the 8mm and think area, some of you then put 10mm area cables in for lightning protection = WRONG the minimum area is 50 square mm and 2 down conductors for lightning protection, AGAIN, solar panel earthing is NOT for lightening protection. So lets stop pretending that a 6mm square area earth wire is going to afford ANY lightening protection, also lets not confuse surge protection MCBs (surge induced by lightening) with lightening protection systems either, surge MCBs clean the +VE and -VE power wires for DC, clean the LIVE wire for AC, the Neutral wire does not normally need to be cleaned for AC because we are TNC-S and Neutral is already earthed, unless you live on a farm with sub-db boards far away from the eskom point of control, you probably will never need to have 2-pole (1+N) AC surge protection, AGAIN Surge MCBs have nothing to do with the reason that solar panel chassis earth wiring is required it is a different 3rd subject area. SANS NRS 97-2-1 regulations clearly specify when Earth spikes should be used and clearly specify that the earth spike should be connected to the Eskom Earth. Gerrie is 100% right that NRS97-2-1 is the place to look. B.3.2.2 specifies "not required" but "preferred" for embedded generators, this is expanded upon per system connection type in the connection diagrams at the end, it also specifies that if you use an earth electrode that 6mm is likely not enough for the connection to eskom, B.1.5.2 states that it must be at least HALF the area of the supply wires which are usually 16mm for domestic supply, so that means the COMPULSORY interconnect between the Earth Spike and Eskom is usually 10mm for 60A connections but may be 16mm for 80A connections

The manual for the EM24 says that pin 9,11,13 are to be earthed, these are the S2 or "negative" terminals The 150/5 CT I am using = Schrack MG900227 (Austria) says (on the picture on the front of the actual CT) that S1 should be earthed So that got me thinking about polarity and second guessing myself, so is this correct ? 8,10,12 = Positive = S1 Cable which connects to terminal 1 or S1 or K on the CT 9,11,13 = Negative = S2 Cable which connects to terminal 2 or S2 or L on the CT I have installed with earth on Negative as per EM24 instructioins and it works fine, so perhaps the Schrack picture is wrong or perhaps it doesn't matter as long as you only earth one of them, either positive or negative

The OverFrequency 1 bar is specified above and in the manual as a default Hysteresis 1.45 when it is actually a default of 1.95, do not change this parameter, it is a "copyedit error/typo" in the manual and is not intended to be changed from the default value

Lets not forget that DVCC limits overall battery charging and VEConfigure limits the Inverter Charging (Grid)

25% of NMD = 15 Amps AC for Single Phase Domestic Supply This is 3,450 Watts on the AC side, there are losses to take into account which means 70Amps on a battery charging at 54Volts Controlling overload when charging on a dark day is no simple task, especially if your customer is single phase with heavy usage, heavy usage customers have more battery and hence on a dark day the battery is way under capacity and you want a lot of grid power to charge it, if your customer draws 8kW and you add 3,450 to that you are going to get a problem, heavy usage users tend to have bigger inverters eg 10kW, which can handle the 8kW load, but that won't prevent overload conditions, if you allow the more powerful inverter to grid charge with more than the 25% grid charging permitted by Eskom then the likelihood of overload goes up exponentially. On a Victron system there is DVCC to limit charge current to the maximum permitted 25%, but sometimes a larger domestic supply is the only answer

Getting VEConfigure working on a Windows PC is a mission, so how is it done with apple MACOS and Parallels Desktop on an M1 processor, I got the software loaded, but next comes getting the device driver and com port working, anyone done this ?

Does anyone know a counter reset to force the venus OS to forget its history, just added a third battery and solar panels and don't want to wait 3 days

I noticed that the Victron Pre-Built Anti Islanding Box for this has a D-Curve Legrand D63 6000 MCB (10 * In) for an Inverter that only supports 2*In (e.g. 2 * 100A on the Quattro), anyone got any idea why this is, since the requirement is to make sure the inverter input connection is compliant, I would have thought that a C-Curve (5 * In) is all that is needed if the box is going to sit in front of a Quattro AC Input, this becomes particularly important ($$) when you move up the Current ladder to 60kVA and 90kVA installations

This is an interesting point, I am hearing that the CoCT has rejected some applications with non compliant Inverters, like for instance a Victron Quattro (1 relay), even though it has an anti Islanding device with it (Ziehl - 2 relays), if this is actually the case, then the Quattro can ONLY be used for "Nearly Off-Grid" configurations and not for "Grid Connected" configurations, which would mean a 3 phase 30kVA installation would need 6 * MultiPlus II 5kVA instead of 3 * Quattro 10kVA and a Ziehl

Thank You, that sounds like a great idea, 16mm slotted trunking takes up 1 DIN MOD since I have the Intermediate relays in the same position on each row it can go across all 3 rows of MCBs in the DB Board from top to bottom to deliver the DC control wires and then from the DC panel on the left hand side of the SU7.

Anyone know the regulations on low power DC signal cables for relays in the main AC Inverter Isolation Board also used as Load Control: Here we want to trigger AC transfer switches with a standard 230V/24V intermediate control relays so the purpose of the load control board and main AC Isolation board is as follows: 1) Isolators to Receive Power from Eskom Point of Control Isolator (Usually arriving from Main Load DB Board Top Left) 2) Circuit Breakers for each Inverter Input and Output and 1P Surge Protection Devices for every Live wire 3) Combine Battery Inverter and PV Inverter AC Outputs into common AC output 4) Use ATS to switch between Eskom and Inverter Output 1 or 2 = Bypass Switch (Entire System) instead of a lever handle in a box 5) Use 2nd, 3rd, 4th ATS (Bypass switch per load group e.g. high power loads) here the ATS still switches between eskom and output1 but with different load DB board destination appliance groups (sub DB boards in the same load db board) 6) Present Several Exit Isolation MCBs for return trip to the Load DB Board with has on arrival isolators for the same 7) Meter everything as required in the main AC Isolation board A. Someone suggested I might need a separate DB Board for each ATS, that seems a bit far out and messy when they are using the same two power sources ? Inverter and Eskom The only difference is the target Load DB Board # in the Separate Load distribution Board B. I now want to activate the ATS's using standard 24VAC/DC activation and 230V control relays (Intermediate Relay) Lets look at a MultiPlus II with an Orion 48/24 DC-DC converter as power source for the NO/NC contacts (Blue relay terminals in multiplus) and activator source 24VDC for for the Intermediate relay which switches the ATS using the intermediate relay and ATS 230VAC control circuits You guessed that I now have very low current DC cables in the otherwise AC board to get the intermediate relay to activate the AC ATS, is this OK or have I got to use a separate dedicated micro DB board for the intermediate relays to avoid the DC control signal wires entering the Main AC Isolation / Load Control Board ? C. Using SU boards (Metal, there is a Metal SU7 DB Board with 3 *24 DIN on one door and 3*15 DIN on the other door, can I use this and put DC in the one side and AC in the other side, it looks like 2 DB Boards and each side has a separate door and is isolated from the other side, or is this also going to have a problem with Compliance I can simply buy 2 SU5 boards and put them next to each other, so I can't see that an SU7 DB Board is going to have a problem - or is it ?

The problem with the 3 *3kVA approach is obviously large power devices, and most of these customers want to be moving towards Off-Grid, we would be sending them down a dead end where this can not happen, hence installing 8kVA inverter and moving the DB board to single phase would be my preferred approach, I actually have 3 customers in the same street wanting the same thing, so they can use a different phase each, and eskom remains balanced. But you are right, eventually it will be time to get around to moving them to single phase supplies

I have a Business Client who has multiple DB boards and has specified that they want sub-metering by DB board, they also want a 90KVA solar system THE MAIN DISTRIBUTION BOARD Here each sub-DB board has an isolator and can easily have a meter added, was thinking about the Carlo Gavazzi (CG) EM24 Modbus/TCP version, perhaps this could be used with the Carlo Gavazzi software and that a Victron Cerbo could aggregate the meters into the overall grid input value, any ideas on the best way to provide building by building energy usage summary in a Victron ESS with 8 separate buildings

The two phase story is a good one and affordable