On 2019/06/14 at 4:12 PM, plonkster said:

I don't know. If you know your stuff you design it so that either there is some redundancy, or so that it fails safe (ie a BMS failure causes the battery to disconnect and protect the cells).

Its quite popular in the DIY powerwall scene to make use of contactors with a BMS, which to me makes a lot of sense, you only want that circuit to be completed if the BMS is happy and also present

8 hours ago, PJJ said:

use of contactors

I've never heard anything go clack inside a Pylontech battery, I think they simply use a large FET (or possibly a few of them). But a FET only conducts if you actively push it into conduction, so this is again something that can be designed so that a failure naturally causes the connection to drop out.

4 minutes ago, plonkster said:

I've never heard anything go clack inside a Pylontech battery, I think they simply use a large FET (or possibly a few of them). But a FET only conducts if you actively push it into conduction, so this is again something that can be designed so that a failure naturally causes the connection to drop out.

The Pylon does make a distinct "clonk" sound when they go into error state, definitely doesn't sound like a big contactor but there is definitely something in there, I experienced this back when I was still struggling to get the Pylon and multi to startup before the Venus started up. 

Edited June 17, 20197 yr by PJJ

On 2019/06/06 at 8:06 PM, PaBz0r said:

 

Running 16X335W Canadians in 2SP2  on a 150/35 North and  2S6P on 150/100 East/West. (Will see how that pans out)

How is the East/west string performing on the single MPPT?

 

 

 

 

 

51 minutes ago, MrVolt said:

How is the East/west string performing on the single MPPT?

Hard to say how much oomph I am losing by using a single MPPT.  It does jump around a bit, but basically peaking at 2200w. The cost of another MPPT vs how much I am missing out on would perhaps give clarity if it is worth adding another.

 

@PaBz0r What do I need to connect my Pylontech to my Victron Inverter and mppt? I believe the cables that connect directly to the battery are special for Pylontech? Can these connect to a busbar and then I make my own cables from busbar to inverter and mppt?

46 minutes ago, deapsquatter said:

What do I need to connect my Pylontech to my Victron Inverter and mppt

You need a Venus device, such as a Venus-GX or a Color Control GX. This device connects to the inverter and the solar charter using individual cables. And then you need this cable to connect the Pylontech battery to the Venus device (type B). Or roll your own.

54 minutes ago, plonkster said:

You need a Venus device, such as a Venus-GX or a Color Control GX. This device connects to the inverter and the solar charter using individual cables. And then you need this cable to connect the Pylontech battery to the Venus device (type B). Or roll your own.

Thanks - I have a Venus-GX. I'm more confused with the specifics of the actual battery cables that run from the battery to inverter and battery to MPPT.

Edited July 8, 20197 yr by deapsquatter

51 minutes ago, deapsquatter said:

actual battery cables that run from the battery to inverter and battery to MPPT

You don't need to do that. The Venus device relays the battery info to the inverter and the MPPT using the existing cabling. No additional cabling is needed. Just turn on DVCC on the Venus device.

For setups with smaller inverters or where you only have DC loads (and no inverter), then things change a bit. Then you can wire the dry contacts on the battery to the remote connections on the inverter/mppt. Then you essentially have analog signalling. But in this case, you don't need to lay down any more copper.

Had an Alarm this morning.. Overload L1. Not sure what to make of it, normal things running which have been running from the start. The Geyser is on Non-Essential, so if the grid failed that would of switched off, but it seems the grid did fail for a brief period according to my wife, because the oven clocks were off. 

Was not pulling much more than 2800 at that stage, had to turn the inverter on and off again to get it working.

On 2019/07/08 at 10:49 AM, plonkster said:

You need a Venus device, such as a Venus-GX or a Color Control GX. This device connects to the inverter and the solar charter using individual cables. And then you need this cable to connect the Pylontech battery to the Venus device (type B). Or roll your own.

Thanks. I rolled my own. Switched system on for the first time today. Grid and Solar not yet connected. Is there a way I can confirm my cable works and the Venus and battery are talking to one another?

16 hours ago, deapsquatter said:

Is there a way I can confirm my cable works and the Venus and battery are talking to one another? 

If the battery shows up on the Device List of the Venus device, then it works.

3 hours ago, plonkster said:

If the battery shows up on the Device List of the Venus device, then it works.

hmm OK thanks - my RJ45 crimping really sucks 

On a lighter note. A while back a client ask me to help him install a few IP cameras and I agreed. Told him we will have everything up and running in  3 hours max. 8 hours later after re-crimping 99% of the RJ 45's about twice because nothing worked, and after suspecting bad quality CAT5 and who knows what else, I started inspecting all the RJ45's and realized my crimper has worked out after years of use and were not making a proper crimp anymore. Went and fetch my not so favorite backup and all was fine after that.  Immediately after that job I ordered a new crimper from my favorite online store in America, and am very happy with my new crimper.  Afterwards I realized that was also the reason i had to re-crimp a Pylon Cable a couple of times a few weeks prior to the camera incident. 

 

3 hours ago, deapsquatter said:

my RJ45 crimping really sucks 

I also blamed myself (Getting old, bad eyesight ext), maybe check your crimper. 

5 hours ago, deapsquatter said:

hmm OK thanks - my RJ45 crimping really sucks 

Managed to get it working after the 4th attempt. Gonna need to buy this cable from somewhere cause mine ain't gonna last.

So my geyser burst, got a replacement and 2kw element, this makes a difference as my batteries don't have to pickup some load, which I am happy with.

I am thinking of swapping the 150/100 MPPT for two 150/45 for the East/West configuration.  This will mean the PV Combiner box will likely need to be changed and the layout will also be impacted by this.

If I do swap out the MPPTs I am thinking of changing up the trunking and DB to get the install a bit neater.  This is where I need some advice:

1. I think a 3 row db will work better than having a separate DB for the change overs, is it allowed to have the change overs in the split db or even in the main db where the grid comes in?

2. Where is a good place to look for nice trunking and t-pieces/accessories, my OCD has kicked in and some of the joints are really not up to scratch.

Then some safety concerns:

1. I also do not have disconnects between the PV combiner and the MPPT, which disconnects should I look for and are well priced? 

2. I also do not have battery disconnects, same as above what should I look for and are well priced?

Then some other SANS concerns:

1. The main db with grid input does not have an ELB anymore, the only load that has remained there is the oven,  is this a problem?

2. The geyser which is on non-essential on its own, also does not have a ELB, I recall that this is a requirement?

 

Any comments welcome.. I am still waiting for my COC.. but not getting much straight answers when difficult questions are asked regarding the above.. makes me a bit worried..

 

 

 

Seems my previous post has slipped through the cracks  I have in the mean time found: http://www.cabstrut.co.za/ for some trunking.

Also I found a document relating to the grid code and Loss of Mains detection, I think the issue I had relating to overload was likely caused by the LOM setting: https://www.victronenergy.com/live/ve.bus:grid-codes-and-loss-of-mains-detection#veconfiguregrid_codes_loss_of_mains_detection

Can anybody confirm what the South African grid code settings is for LOM? A or B? Has anyone experienced issues with this?

 

 

2 hours ago, PaBz0r said:

Can anybody confirm what the South African grid code settings is for LOM? A or B? Has anyone experienced issues with this?

B is good enough. A is more sensitive and can cause nuisance grid rejection.

On 2019/07/17 at 10:35 AM, PaBz0r said:

1. The main db with grid input does not have an ELB anymore, the only load that has remained there is the oven,  is this a problem?

I don't know. The grid code says all sockets must be protected by an RCD. The stove generally doesn't have a (normal?) socket and is more-or-less hardwired in. In theory, as long as it is well earthed it is safe. Personally I would want an RCD on it though. It's in a place where your loved ones can easily touch the metal parts, and it gets exposed to liquids. Just don't do it man.

On 2019/07/17 at 10:35 AM, PaBz0r said:

2. The geyser which is on non-essential on its own, also does not have a ELB, I recall that this is a requirement?

There is a new requirement that requires installing a separate RCD for the geyser, but it has always been a requirement that it must have residual current protection.

If space is a problem, use an RCBO (combination overcurrent/residual current device). Then it should be a simple swap-out operation, just replace the existing isolator with one of these.

Thanks @plonkster. I was also just thinking of getting them added, as you say safety is important.

I will confirm what my LOM is set to, hopefully A then I know B should sort me out. Was bothering me what caused it, but I had a grid failure thus it must be related to that as no major consumers were running at the time to cause an overload.

 

 

Edited July 23, 20197 yr by PaBz0r

On 2019/06/13 at 2:41 PM, georgelza said:

I'm saying, have the MPPt get what ever it can from the PV, and then past on to the batteries whatever it can, I've been told the Pylontechs will throttle their side anyhow, if it's getting more than it can handle.

G

I have been wondering about this again as I want to split my east/west to two MPPTs. How many Pylons do you have and have you seen your array hit above the Pylon charge amps? I want to try model my situation, as I only have two us3000b, which is stated to handle 37A per module, thus 74 is easily reachable even with my current setup, thus I am already throttling myself during peak hours, but losing out later in the afternoon as the east pulls down the west.

Ok so they are currently busy splitting my East/West to two 150/45 MPPTs. Hopefully my afternoon will look a bit better going forward.

Additionally sorting out some other concerns:

• EL on the Geyser. 
• Battery Isolator - Jean Muller Keto - 3 Pole
• PV Combiner box upgraded to handle 6 Strings
• Battery Ground.. (discovered it was connected to nothing)
• Moving the Oven to Non-Essential ( From my usage and it being very new, it seems that it does not use that much, going to give it a try on batteries )
• Connecting a Sonoff to the extractor Fan, which I have now flashed and setup in Node-Red. Will check the Battery Temp and then decide to turn it off or on.

Overall the system up to now has run well, my first account I got with a full month was 60kw from the grid, this included some geyser once or twice, the oven every other night and the 50w Grid setpoint from the inverter. Lets see if I can get that down further with my oven plan.

Will post some pictures when they have found space for the two new mppts.. this is getting interesting

 

Edited September 4, 20196 yr by PaBz0r

@PaBz0r what has your highest daily yield been so far ? 

@Mstott The east/west started clipping the 45A limit I set on the charge controller the last few days. 

You can see that the East/West jumps around more than the North facing. 

From the other thread where it was discussed how much in theory one is losing with using a single MPPT,  I am interested to see how my peaks, early morning and late afternoon will change with the new setup.

We had a bit of set back yesterday.. The power cable for the Venus got cut when they fiddled with the trunking, blew the fuse. So my system is not operational today and they also have not yet sorted out all the other things. 

The strings have been connected and the charge controllers installed, still need to sort out the trunking, this cupboard is really getting crazy:

 

 

 

 

I'll be holding thumbs for you ! I'm sure you are going to see an improvement.

Ok it is alive again,  performing very well seeing that the rain cleaned the panels and the cloud edge effect today. The MPPTs are not throttled anymore as the combiner box has been sorted to handle 6 strings with correct fusing. Some trunking work and a plug point needs to still be done, Sonoff working well with extractor.