It’s no different from a single victron really, each one has its own mains feed via a breaker and isolator and each one draws from the same bus bar - there’s no other wires between them apart from the comms cable

​@@eliotmansfieldDo you use pure sine wave with two or interlaced sine wave?!

@@patricklyons7683 Not sure what you mean - they are in parallel - so i get double the capacity on a single phase. It’s not split phase if that’s what you are asking

yeh maybe so, seemed to be the right thing to do given the hefty dc power that’s close to the ac. It does trip occasionally, which mainly turned out to be my florescent lights in the garage.

The MP 2 is transformer isolated so a type A should suffice.

you set it in veconfigure - (not the cerbo gui) - mines parallel so it’s set to 50 amps to arrive at 100. Essentially you want to set the charge rate high enough to charge in your window - as there’s no value in charging them faster than required

@@eliotmansfieldthanks, luckily I had checked the box in veconfigure so was able to adjust in CERBO after all. Cheers. Can you tell me how you handled the neutral tails from the RCBOs, do they all common up and connect to the neutral under the changeover switch. I’ve commoned them up first and used a single cable to connect to neutral. Do you know what current would go through the tails? Graeme

@@graemekennedy7137 I’ve not removed the cover - so not sure how the. spark did it - but I would do as you describe personally. Total load is fairly low, say 20a or less, because it’s just led lights etc. I would probably squish the wires into a bit of 4mm cable personally

not quite sure what you are asking - can you draw it out? eliot at mez.co.uk

will take a look

made no changes to the ground relay. It needs to be enabled otherwise the rcd (gfci) wont work.

I dont think you understand how it's wired. The 25mm tails go into the consumer units as normal. The two victrons are on their own 20A RCBO's, the only light loads (less than 10amps) are downstream. The entire house isn't downstream (after) the victrons, study the drawings again. The big red changeover switch is just switches the between Victron ACOUT1 and Normal Grid power - so allow those loads (the RCBO's on the lower half of the consumer unit) to work if the victrons are powered off/fail. (8:17 on the vid)

@@eliotmansfield Thanks. I see separate line conductors from the main switch, load side, to both the Victron RCD and bypass mcb as well as the busbar connection to the unprotected mbc section. Are they all connected to the same line terminal on the main switch?

@@mfr58 the circuit diagram (visio) in the video - i don’t show live and neutral for simplicity. Is that what you are referring to?

@@eliotmansfield Yes the diagram. It is a practical question of wiring rather than operation theory. How you connect two large CSA conductors and a bus bar to the same terminal on the main switch.

@@mfr58 probably need to take it offline to explain - ping me an email.

It was originally a single unit then expanded to two units. You power the units from the battery pack with the ac isolated to do all the configuration, then you can add the ac side

@@eliotmansfield cheers for the reply, I will do the set up with no AC cables connected to the inverters! 👍

The type B is 30ma - as I already have 100ma in my upstream distribution box (which is not typical). Pressing the test button on the type A rcbo’s doesn’t cause the type b to trip. There is a chance that the type B could trip from a downstream load on a type A

@@eliotmansfield that’s interesting. Could you end up in a scenario where the downstream load trips the type b, the batteries kick in due to grid loss and then the rcbo trips? And so the trip time on the downstream load is too long?

@@jameswestcott4191 Yes that could happen. If I didn’t have upstream 100ma rcd’s I would of considered putting a 100ma type B in instead (if such a thing exists)

microsoft visio

the internal contactor can only handle 50a (per unit) if your total loads will never exceed that and you have nothing upstream on ac in, then yes by all means use that. As you can see i have quite a complicated setup with multiple consumer units so it’s not physically practical for me to

Victron state not to oversize the AC cabling on a parallel setup. So you either feed it with 2.5mm and 20A breaker or 4mm and 32A breaker, the latter would be in excess of what it will ever draw. Now I don’t know what Victron define as ‘oversizing’ and if 4mm/32a would be too much, so I went with the lower cable&breaker - at peak load I’ve only seen 18A being drawn, so under the capacity of the breaker just. I would sorta prefer 4mm/32a - but as i said, Victron dont explain what their definition of oversizing is. (bearing in mind that 18A x 2 x 240 is 8640 watts total). I’ve had a thermal camera on it and there’s no hot spots

Isn’t a 20A breaker cutting it a bit fine or do you never charge from the grid?

​@@eliotmansfield doesn't the Multiplus manual state that a 50A breaker should be used? Or does this change when you have two MP in parallel? I currently have a MP 5000kVA and my electrician used a 50A MCB with 10mm2 cable going to the MP AC_IN via a 63A isolator. I am thinking about getting a another MP to run them in parallel and I was thinking this would just mean another 50A MCB and isolator would be needed for the AC side so I am just curious why you have limited the MP to only 20A each?

@@pauldunn Because the loads on the output will never exceed 20A (or 40A parallel). 50A is the maximum downstream load, in which case you would use a 50A upstream breaker. It depends on your configuration - see my first video on the different ways of wiring these up