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Planning my solar "freedom - Pretoria


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3 hours ago, MorneDJ said:

It reports that the batteries are flat, so I am leaving the system to charge the batteries.

Did you install the Pylontech's as planned, and if so, What cable did you use to connect it to the Venus?If you log into the Venus, Can you see the Pylontech's? 

The one that comes with the Pylontech cable pack does not work on the Victron system, the pin-out has to be changed. 

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I cannot see the pylontech batteries. I made a new cable with pins 2 - 3, 8 - 5 and 7 - 4. I tested the cable and it dies work, but one never know. The batteries charge and show no alarm currently with the cable I made. I will see if some-one in Pta stock that cable and I will buy one.

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1 hour ago, MorneDJ said:

I cannot see the pylontech batteries.

Please check the following, and remember to mark the RJ45 that should to the battery side and the other one that should go to the Venus side. It will not work if you turn the cable around.

Pylon.JPG.18e70acb2489d6542b2c2f4d94baee20.JPG

With your inverter there was suppose to be 2 Blue RJ45 like jacks (VE.Can Terminator) . The one should go in the Open VE-Can socket. 

 

1159486086_Pylon2.thumb.JPG.4ab46faa85824cd33bf1e39cf0b2667e.JPG 

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Thanks. Everything is setup as with the post, but I cannot see it. Waiting for Solarshop to call back to tell me if they have this cable. 

And the invertor does not work as planned. It does not use any of the solar energy, so the solar panel energy is just used to keep the batteries charges (float?) it seems. What am I missing?

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14 hours ago, Jaco de Jongh said:

Normally 1 is On, 0 is off and II is charger only. 

Correct.

Also check the version of the firmware on your Venus device. Sometimes older stock comes with some seriously old versions. Better update that to 2.31 soonest.

14 hours ago, Jaco de Jongh said:

 had the same issues, he had to change his RCD to a better one that could "Handle the Inverter" . Plonk please help out here? I cant find the thread nor can i remember the specs of the RCD. 

The first important thing I learned in the mean time, is that the Multiplus-II does not use the same method as the Multigrid (which tripplet and I have) to test its bonding and relays. So it is a lot less prone to the kind of tripping I experienced.

But let's see if my experience helps here. The first question: Which RCD trips? You say it's the one on the main board, so I have to assume this one is BEFORE the Multi.

Second question: When does it trip. Does it trip the moment the Multi is turned on, or does it trip when the Multi does its relay test (the 8 closely-spaced click-clacks as the inverter connects to the grid)? The case I dealt with was during the relay test.

Because it's the RCD on the input tripping (not on the output, which was my problem and was caused by transient spikes during the relay test, solved by fitting an extremely expensive impulse-resistant RCD), and because it is the Multiplus-II (different way of testing), I have to assume there is another problem in your installation. Did you perhaps in the past also have RCD trips when the power came back after an outage?

I suggest you treat this like any RCD problem. First test the RCD (using an RCD tester, they are cheap and handy to have around, around R300). Maybe you can borrow one. Most RCDs trip somewhere between 15mA and 20mA (even though rated at 30mA, the regulation states that it MUST trip at 30mA but MAY trip as early as the halfway point). If that checks out, then you need to apply a process of elimination. First disconnect all loads (live and neutral) and see if the Multi can connect to the grid with nothing on its output. If that works, then introduce loads/circuits one by one (ideally isolate both the live and neutral to each circuit... it is possible to have a neutral/earth ground fault too!). If you are lucky, the problem is just one circuit/load. If not, you will find that certain circuits are fine but others (together or individually) all cause the problem.

These are the cheap tests. After this you need an earth leakage clamp meter to help you locate the problem. Can't debug if you can't measure.

Also... one mistake my sparky made (and I missed) many years ago: We had the neutral side of the Carlo Gavazzi connected to the neutral bar (post RCD), but the Carlo Gavazzi was installed BEFORE the RCD. The tiny bit of current the Carlo Gavazzi uses was therefore in imbalance. It worked for two years before it failed one random laundry day...

 

Edited by plonkster
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The simplest solution -- if you are sure you made no mistakes -- is to simply NOT feed the Multi from after the RCD on the main board. Feed it from before the RCD (obviously install proper overcurrent protection, and ideally an isolator in both lines). I prefer using a dedicated higher-rated RCD (100mA or 300mA) just to provide equipment level protection to the Multi itself (and some selectivity, the downstream 30mA one should always trip first), but that is not required... just a good idea. In short: Don't use the RCD that you use for the non-essential circuits (the others in the main board, I assume you did not put the whole house onto the Multi) to also protect the Multi.

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System is seeing the pylontech batteries after driving to Current Automation to buy the Victron cable. I will check tonight what the differences are between my cables (I made 2) and the Victron cable. I also got the MK3 connector to see if I can check the settings on the Multiplus.

The trip seems to be sorted, I changed the earth leakage CB. I assume that this is the RCD?

The multiplus is on, but:

- When the multiplus is connected to the grid, it use the power from the grid and not the solar panels which is now in full sun and should be able to deliver at least 1 kW.

- When I remove the grid power it seamlessly start using the power from the solar panels, which is not alot. The backup power only do the house lights and the lounge area (TV and PC), around 500w max.

Will check the settings tonight. 

Can I enable the grid feedback to see if my meter run backwards (once my issues are sorted) ?

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12 minutes ago, MorneDJ said:

I also got the MK3 connector

It sounds to me like the inverter is not programmed at all. If you didn't have the mk3, it's likely still on old firmware too.

On the Venus device, go to settings, then 7 items down to ESS. If this page shows that the ESS assistant is not installed, that explains your entire issue. It means the inverter is acting like a UPS.

First upgrade to firmware 459. You can get that by registering at professional.victronenergy.com. Part of the VE configure tools is a tool called VE.Flash. Follow the instructions (blindly, it is normal for the inverter to appear dead in the middle of this) and flash new firmware. Then you have to load the ESS assistant with VEConfigure.

If you need help... well maybe I can hook you up if I find a gap. This isn't really an official support channel 🙂

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17 minutes ago, MorneDJ said:

- When the multiplus is connected to the grid, it use the power from the grid and not the solar panels which is now in full sun and should be able to deliver at least 1 kW.

Did Current Automation setup the inverter for grid tied operations?
And did they update all the firmware on the devices AND the inverter?

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OK, I got the ET112 working, and I can see the assistant, but it does not allow me to start the assistant, as I have to select a Grid code selection. When I try to select South Africa: NRS 097-2-1:2017 it asks for a password, which I do not have. Anyone have this password ?

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2 minutes ago, MorneDJ said:

Anyone have this password ?

Interesting. I could set mine the first time after which I could not change it.

Suppose PM's are flying behind the scene, if not, ask your supplier.

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I found a better, almost "how-to" installation page at https://www.victronenergy.com/live/ess:quick-installation-guide. Fact is, that up to this point I had to source installation information from various different sources, and I am still busy sourcing information.

As the system was just working as a UPS, I just threw the grid switch (to the Multiplus) and the lights and lounge was on solar the whole time yesterday, going to batteries last night, with the battery at 66% at 6 this morning. Sun is happily charging the batteries this morning.

I have taken alot of photos, and will post a proper thread in Members installation when the pressure drops a bit this side. Between work, family, more work, studies, work and doing this solar I have less time each day, but I will get there.

Edit: I only installed the first 6 solar panels so far, so a potential maximum of around 1,800 W. 

20190625 - Remote Console view.jpg

Edited by MorneDJ
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Nope, I did not, thanks. Goodness, now to find the:

  • Battery capacity of the Pylontech 3000US (75 AH? each)
  • Battery system (LiFePo4 with VE.Bus BMS, two-signal BMS or other ?)
  • Sustain voltage ?
  • Dynamic cut-off voltages ?
  • Restart voltages ?

Anyone on Victron with pylontech batteries, could you please post your settings here ?

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31 minutes ago, MorneDJ said:
  • Battery capacity of the Pylontech 3000US (75 AH? each)
  • Battery system (LiFePo4 with VE.Bus BMS, two-signal BMS or other ?)
  • Sustain voltage ?
  • Dynamic cut-off voltages ?
  • Restart voltages ?

Most are on the inverter if memory serves.

Best to get the Pylon settings for others - maybe I should add it to that document.

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That would be brilliant. Now just waiting for a pylontech owner to chip in, else I will ask in the batteries section in an appropriate section. Can probably also call Wessel from Re-Volt, he should know that.

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22 minutes ago, MorneDJ said:

Battery capacity of the Pylontech 3000US (75 AH? each)

Normally you'd divide the capacity into the nominal voltage. But the 2000Wh model is really 2500Wh, and the 3000 model is really 3500Wh (down to 0% SoC), so the figures are 50Ah for the smaller unit and 75Ah for the larger one. Multiply by number of modules.

This figure isn't super important. The Multi's internal SOC mechanism uses that to calculate when the battery is full, but since you use the SOC from the BMS anyway it is not a trainsmash if you are slightly off. A value that is in the ballpark is perfectly sufficient.

25 minutes ago, MorneDJ said:

Battery system (LiFePo4 with VE.Bus BMS, two-signal BMS or other ?)

LiFePO4 with OTHER BMS. Last option on the list if I recall. Unless you have Victron batteries, you're not using a VE.Bus BMS (I have one of those). And two-signal is for batteries that only have two relays (one closes when empty, the other when full). The pylontech does have that, but you don't use it, you use the can cable.

27 minutes ago, MorneDJ said:
  • Sustain voltage ? 
  • Dynamic cut-off voltages ? 
  • Restart voltages ? 

Normally the defaults are fine for a 16-series battery, but the Pylontech is a 15-series battery, so these all have to be taken down a bit.

If the battery has been discharged below the cut-off voltage (determined by the dynamic curve, which I will get to next), it goes into sustain mode. In sustain mode it just tries to nurse the battery until solar can pick it up again. It goes back into self-consumption mode once the sustain voltage has been exceeded by a certain margin (which you can also set). So don't set sustain too high. Something like 49V (3.25V per cell) is perfectly fine.

The dynamic cut-off curve is an improvement on how inverters normally do this (which is to have a single low-voltage disconnect). What it does is allow the battery to dip lower at higher power levels. An LFP battery that's below 49V at no load is almost flat, while the same battery at 2C discharge will dip that low even if full. The BMS is in charge in any case and disconnects if you overdo it, so lots of people simply configure the whole cut-off curve between 45V to 48V. You can play with this, but again it is not too serious if you get it wrong. If you get it too high, then the system might go into sustain prematurely (eg it might go into sustain at 30% SoC), then you simply lower the curve a bit. If you get it too low, the BMS will kick out and leave you in the dark.

The default of restarting at 0.6V above sustain is good. Don't mess with it unless you have good reason to.

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3 minutes ago, plonkster said:

The default of restarting at 0.6V above sustain is good. Don't mess with it unless you have good reason to.

Or maybe it is 1.2V. I can't remember. It might be 0.3V per 12V increment.

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