Hi all, this might be a dumb question so don't shoot me.

I am adding another battery to my parallel 5kw inverter system.  Can I switch it on the app to 'no battery' while keeping the inverters on online?  My expectation is that I will then be able switch the breaker on the existing batteries off and then have zero Volts on the battery busbar.  Then I will add the new battery, connect it to the busbar, flip all the battery breakers to 'on' and then change the inverter via the app again to 'Lithium'.

 

Do I run any risk on the inverter? Or is it OK?

PS. I know I should only add the battery if it is similar state of charge.

will give my 2c worth, I have also changed the 5kw SunSynk inverter to no battery and if I remember correctly it rebooted the inverter and I lost power while it rebooted. If you have a changeover switch, maybe switch over to Eskdom power first then do the change you looking to do.

Thanks for the input. I've changed from Lithium to AGM V and back without an issue before, but never to 'no battery' and back. 

Edited February 15, 20251 yr by gimme_power

It will scream at you NO BATTERY and then drop the load, safer option would be to switch to grid to service the load while you work on the addition.

I saw that happen when they were installing my system, battery was shutdown...gave the on screen message is green NO BATTERY and then it dropped the load.

Probably also just safer to shutdown the system, do your changes and then start everything up again.

Switch off the inverter, batteries and solar. Put the change over switch in your DB to grid. Now you can safely work on the installation. 

Remember to have the same effective length of cable to each battery.

Apologies, also switch off the AC breaker feeding the inverter! I would do that after the inverter switched off.

Thanks @frivan I was hoping to do the changes without bringing the inverter down.

16 minutes ago, gimme_power said:

without bringing the inverter down

Anything is possible, people are working on live High Voltage lines. However, for your job, consider the PPE required and equipment being put at risk. Probably a shutdown is worth it. If your load is truly critical, you should also have a UPS installed.

1 hour ago, gimme_power said:

Thanks @frivan I was hoping to do the changes without bringing the inverter down.

I can't see why it can't be done as the inverter will then become Grid-Tied and if utility and solar is present it will service the loads blending the 2 sources. I have never used the "no battery function" on Sunsynk but let us hear from our installation specialist @Steve87 on his thought's.

According to me you need to be disconnecting and connecting the DC cable on the battery input of the inverter. There are nice big capacitors connected to this. While 50V won't kill you, I can't imagine that the electronics will like a short.

I ended up going the conservative route and brought the system down before making the change. But I would still be interested in hearing from the experts.  If it is dangerous you would think that they would block you in the app

I got the Kodak OG and by accident pressed the on off switch on my new svolt batt while all was connected and running. I only noticed it when the no battery warning came up the screen. I even opened the batt switch and closed it again before I realised I switched it off at the switch. This was a few days ago and up to now all is good.