my installation

[Bernd]

See attached my current installation process. Still not final after all this time, but it is very hard to understand all the details, which are so easy for all of you… For me it is complex…

You solve one miracle, 2 new open up….

Here are my open questions:

1.) the forums seems to be unable to accept pictures via chrome. only for me?

2.) any comments on my installation are highly welcome.

3) I´ve added a main switch, but this seems to be unsupported or not OK. Did someone do the same or what are your recommendations for a main switch?

4.) I´ve set MAX SOC to 99% and now the CFET seems to not turning OFF (between 98 -> 96%) , but the DSSR20 are switch to HEATING. Is this OK and the normal behaviour?

5.) is there a better / easier way of cableing the DSSR20 esp. with the negative connections? I will end up with 10 DSSR20 and this will not look nice at the end? Does anyone have a Foto of an installation with >8 DSSR20 connected to solar?

Thanks for your support out there

[michael clark]

  I bought some dinkle terminal blocks where I am going to combine some of the 10 AWG PV wires maybe 3 into 1 then 1 cable for every 3 or 4 to the negative bus bar. lots of wires for sure but they work great. I have a thread at diysolarforum with some pictures there. i have 10 dssr20's mounted but using 5 at the moment. waiting for snow and cold to improve for more exterior wiring. also, I use 2 busbars one for the DSSR20's and one for the battery and inverter. i connect the dssr20 busbar to the main busbar with 1/0 cable. 4/0 to the inverter from the battery with class t fuse in-between.  

in your photo you need to remove the small sense wire. you should only have 1 sense wire to the dssr20 and it should be connected to the one that says batt. that will stop the heat light issue you encounter. 

i assume your dssr20 does not use the diversion function and you are only charging a LiFEPO4 battery. 

that assume word is always a bad one.

[michael clark]

also you need a 1amp fuse in the positive sense/control wire from the dssr20 to the dect16. I bought a standard automotive glass fuse holder that had red leads attached. then solder or crimp it in between. i soldered mine the taped over it with electrical red tape.

[michael clark]

you may need to double-check with Dacian --- your SBMS0 is an older model so the DSSR20 may be different than mine also

[Bernd]

I think i have the latest SBMS0, but only Dacian will know

[Dacian Todea]

Bernd,

1.) Not sure I use Google Chrome browser in Linux and it works.

3.) Please remove that switch as you will damage the SBMS0. If you are worried that you can short the current shunts then have those in a separate box.

4.) CFET is just what the ISL94203 is reporting but the SOC limit is done by the micro controller so charging is disabled and that can be seen if you look at the bottom of the screen where if the left bar where PV current is shown is not highlighted the charging is disabled. But unless you set the max SOC to 99% then charging will be done based on voltage you need to set to 98% or below for the SOC limit to work.

5.) You can manage the cables better to look nicer. You can also just use a single wire like 24AWG to first DSSR20 and then jump from one DSSR20 to the other.

2.) That case seems made of steel and if so you will want to use some insulating grommets there wires pas trough like those for PV panels.

Those look like maybe 100Ah cells and if that is the case they are to small for 80A charging assuming each DSSR20 is connected to two parallel 60 cell panels. Same for the small 100A current shunts as they will not be capable of 80A continues just 66A is the max limit for those. And I see you are likely using dual PV array and that will help but not sure how many more DSSR20's you will add.

The inverter I thin has no remote ON/OFF as it seems to be made with momentary ON/OFF switch and that can not be controlled by SBMS0 unless adding extra custom circuit shown by someone here on the forum. I see you added a BP220 to disconnect the DC side of the inverter but Victron is not recommending that and the BP220 may get damaged.

The cells should be compressed for long life. 

You will need to add a fuse 1A will be OK on the positive supply going to the DEXT16's

[Bernd]

I will review all this and take care of your recommendations (step by step).

I have 8x 150Ah cells, but will update to 32x 280Ah cells soon. I´m not charging with more then 35A at the moment.

Will take care of the missing fuse, remove the main switch and update my cableing.

 

Regarding BP220 and my inverter. Which Victron (?) inverter should be a long time excellent choice to get rid of my 2KW inverter?

I think I will need maybe 5KW and i will stay at 100% offgrid.

The inverter Phoenix Smart 5000VA should be the best choice? right? Other options on the market that I should concider?

[Dacian Todea]

Brend,

If is just an inverter then there are quite a few good choices and Phoenix Smart is not a bad choice tho not sure what is the price for that. Many times two smaller 3000VA inverters in parallel may be more cost effective

I was looking at an inverter for my own use and this seem great https://www.steca.com/index.php?Steca-Xtender-XTM-en not sure about the price that may be higher than Victron.

I was looking at the XTM 3500 24V but a coppy of the original (or maybe the original but re-branded) https://www.aliexpress.com/item/32914668898.html this can handle 9000VA surge for 5 seconds and has only a 12W self consumption so it is superior to anything else I seen. The 5000VA model costs double but is not double in capability so two 3500VA in parallel will be more capable at the same cost.

The larger model has easy remote ON/OFF I will need to look in to more details on how that is done on the 3500VA model but should sure be possible.

[Bernd]

Hi Dacian,

i checked the Victron Phoenix Smart 24V 5000VA again https://www.victronenergy.de/upload/documents/Datasheet-Phoenix-Inverter-Smart-1600VA-5000VA-DE.pdf

and it can handle up to 10k Watt peak and in ECO mode it consumes 2.2 Watt and self consumption should be no higher then 18 watt. The costs here in germany are 1770,-€ incl. tax and shipping.

The ON/OFF switch looks the same as on the BP220. Do you know, if this can be directly connect to EXT IO of SBMS?

 

[Dacian Todea]

Those new Victron models are less available here in north America.  I'm not a fan of ECO mode on inverters and as soon as you have any load that needs to be powered continues you can not use that but 18W is still very good for a 5000VA inverter.

The XTH 5000VA 24V also has an echo mode that uses 1.8W and the peak is 12kVA for 5 seconds vs I think less than 1 second for Victron (not sure about new models).

I'm just a bit biased towards Steca and mostly because I like the way is internally constructed. Below a photo of the XTM 3500-24 the 5000VA has a different case and construction but main points are done the same.

[Bernd]

Thanks for sharing.

I´m not yet a fan of Steca , as up to now I only know these small solar chargers PR1010 which are really really cheap and not state of the art...

I´m still not sure about the options, i will get with sbms0 and the Steca yet. But it has power and a charger.

It seems as if the sbms0 is directly (without extra special hack boards :-)) able to turn of the XTH-5000-24 ?

The option of using it as a charger is interesting. I planned to go with 2x victron 16A chargers (already here) with a small/mid size generater, as this should not happen often in combination with my 1120Ah battery and 5KW of solar.

Also the price is 3800€ for the Steca compared to 1800€ of the Victron.

What I didn´t understand yet: Do I need extra hardware to control (turn off) the victron and/or the Steca? It seems I only need correct jumper settings plus 2 wires. Correct?

[Dacian Todea]

The SBMS0 should be able to turn ON/OFF the XTH-5000 but only if used as an inverter there is no separate controll for charging so that can not be used. But the Victron Phoenix is just an inverter so I assumed that is what you needed only and no grid charging.

If you also need charging the best option is the Victron multiplus or multigrid as those are inverter chargers with separate remote ON/OFF for charger and inverter see details here https://www.victronenergy.com/upload/documents/Manual-Connecting-other-lithium-battery-systems-to-Multis-and-Quattros-EN.pdf  then you do not need to pay extra for the charger part as it just uses the inverter in reverse when grid charging is needed and it is a single unit.

[Bernd]

I think I will go with the Victron Multiplus II 24/3000

It will not give me that much more power as i have today, but i will be more flexible in the future.

Hope this is the right decision....

THANK YOU again

[Dacian Todea]

Bernd,

Yes Victron Multiplus II 3000VA is a good choice. Most people with RV's use the Multiplus (not the II the old one) as they want to also be able to charge from grid.

You can always add another 3000VA multiplus in parallel for 6000VA in the future if you need more power and will probably not cost that much more than a 5000VA version.