Hi @robovanbasten yes if you can replace that Wylex one especially with that recall on one of the MCB’s not sure if your going to fall into that recalled version but may as well upgrade to the 18th edition, PS I would get bigger CU’s as this will give you room for expansion with circuits in the future as your already spending to change them so get the biggest ones for your space, as when my house circuit was stripped from a ring to three radials and 4 or 5 other zones for lighting I started to see the size of my 22way vanish hence why I got the 40way as well
The multi is going to try to cover everything attached to the et112 ie it wants to zero out your grid use not sure if it could be limited to only helping for XYZ kW, you need to have another et112 for the grow watt and show the multi that it has an additional power supply ie solar and then use the grow watt CT on the shower so it generates more and the multi set to feed excess to the grid, that’s how the simulation is playing out in my head, but real world might see it ramping up and down a bit.
Hi @Daza , @DuivertNL , @BjoernK , in the schematic above does anyone know what the purpose of the CT clip around the live cable from the solar inverter?
This is not the victron ct clamp for multiplus, but the victron ac current sensor (ct current loop) this is used on the schematic to measure pv production
Regarding frequency shifting I dont have personal experience but my understanding is that in the event of a power cut the Victron becomes a grid forming inverter, and the Growatt would see that (if connected to ACout 1) as effectively the grid and so would continue to function as normal. If however the Growatt senses a slight shift in the AC frequency from 50hz it would interpret that as an instruction to throttle output, and eventually stop all output if the shift became too large. The Victron controls the Growatt simply by slightly varying the “grid” frequency it produces and slight changes from 50Hz would signal the Growatt to progressively reduce then shut down any output.
Generally correct.
Some years back EU changed the standard from “switch off on high frequency” to “reduce power linear to frequency”. Though exact behavior of Growatt depends on the age of the device. Recent years Growatt throttle linear.
Terms used are: frequency shift, frequency watt, power frequency
The function is part of the grid code.
@Daza@DuivertNL@BjoernK@Roamwood , finally got some dates booked in for my install. First my electrician is coming in next week to replace my old plastic WYLEX consumer unit, and install an earth rod for the MP2. Whilst replacing the consumer unit I’ve asked them to move my Solar PV into the main consumer unit (like the schematic above), question: does this need to be wired in in any special way? I notice from the schematic above it looks like their Solar PV and External ASHP are wired in before the 63 amp RCD?
Following my electricians prep work, I have a Victron Installer coming in the week after to install the MP2 8000VA and Pylontech batteries (2 x US5000). @Daza , they are going to install a transfer switch as you suggested. One thing I’m still not clear on is whether or not I need a [victron ac current sensor (ct current loop)] as mentioned above? Any help on these questions much appreciated. Chris
@Blendworth Hi Jason, are you still an active user on here? I’ve been using your schematic as inspiration for an upgrade to my existing system. Might have a few questions for you if you wouldn’t mind? Chris
Hi @robovanbasten is getting confusing what you are referencing for a diagram but if you just intend the multi to handle critical load and nothing on the AC in of the multi then you don’t need a CT on the multiplus.
The PV wires into an ET 112 and then to the breaker personally I would stick with an MCB for this as solar is very leaky and you may find that following a transition back from island mode your breaker RCBO could trip both of my Solis units RCBO’s tripped so they got dumb MCB’s and no issues (caveat) my house is wired as a TT so has a time delay RCD that monitors everything.
Not sure if you could make heads or tails of my install as I just had to apply for another vehicle charger so this is updated but the multi has no external CT as it only covers the critical load
@robovanbasten that’s by design this as those items have a lot of DC leakage so you could get a lot of nuisance tripping on the RCD, you shouldn’t have that issue because you’re more than likely gonna have RCBO’s, rather than the old dual RCD boards we’ve moved away from that as there is a lot more devices tech that we have that leaks DC and this adds up, so instead of everything going through one RCD each circuit now has a tolerance of the RCOB at 30mA hope that helps
Hi @robovanbasten I’m not much of an active member on here any more but still have a read up on some of the posts on here. I have had a quick read of this post and I have a few comments in reply. Let me know what questions you have as that schematic has changed a bit as I keep improving the system or increasing it a little.
I have a PV system on the AC out1 greater than the 5kva allowed but I have an interlock that in the event of a grid failure, the PV inverter drops to 25% (1.5kw). This protects the Multiplus from damage from being over-powered from the AC inverter.
The CT sensor on the 230VAC from the PV inverter is to provide data into VRM on the generation power and generation energy.
The Annex East DC array is offline.
I use the ET112 on the grid to maintain -30w, continuous export to the grid that way I don’t pull anything from the grid during peak hours.
The EV charger si on the grid side as not to overload the Multiplus. As I would onyl charge during off-peak times, there is no need to power it from the AC-Out side the MP2 as I already hit 50amps in the winter with everything running. Sometimes the MP2 will throttle back the battery charging if I hit the 50A limit as not to go over that limit.
@Daza@Blendworth , well its finally all been installed, and I think its working. Its a MP2 8000va with 2 x Pylontech US5000 and my 6kw Growatt Hybrid on AC OUT 1.
Couple of questions/observations that you guys might know.
I notice in the VRM portal that the battery always seems to be discharging, anything from 50w to 100w, is this normal? I would expect it to be just sat there idling at around 0w until needed.
How can I reduce the charge rate when I force charge overnight? I set a schedule to charge to 100% from midnight to 5:30 am (end of cheap rate). I noticed by 3am they were already fully charged. I’d like to slow that charge down if possible. (I do the same on my Growatt batteries).
I have my entire house loads on AC OUT 1 (expect my car charger). Last night when running the electric shower the MP2 had to make up the shortfall of about 6kw, which it did but the MP2 was complaining of [low battery] (see video below)? The internal cooling fan was running (as expected), but I didn’t expect a low battery warning, given the Pylons were at 48%.
I notice in the VRM portal that the battery always seems to be discharging, anything from 50w to 100w, is this normal? I would expect it to be just sat there idling at around 0w until needed.
(If this is the Pylontechs then yes this is normal as they are actually running/powering the multi)
How can I reduce the charge rate when I force charge overnight? I see a schedule to charge to 100% from midnight to 5:30 am (end of cheap rate). I noticed by 3am they were already fully charged. I’d like to slow that charge down if possible. (I do the same on my Growatt batteries)
but a Node Red would be better for you to automate it, I do a similar thing with my AC Solar and once messed up and thought why is my battery not charging fast I messed up with the code to bring it back to full charge after 9pm lol. I’ll look for my code and you can change to suit. There is a read me which may help but mine is for a different purpose.
Also this will limit charge in the day with solar as well so use its as a time base system to limit charge in the off peak time and return to normal to take advantage of your solar or just let it bump up a little for better charge rate in the day
For the latter low battery your battery bank isn’t big enough see Victron/Pylontech
Hi @Daza , thanks for the reply. I just found that table online and I can see the [Number of Pylontech modules] is based on US2000 battery modules. How do I calculate what number of battery modules I need to overcome this low battery warning? That table says 6 modules for US2000, which is 12kw total. In my head that makes me think I only need one US2000 to add to my existing 2xUS5000’s? (Although it’s probably not as simple as that). Chris
