question

robin avatar image

multiplus displaying low battery alarm and wont start up

multiplus 24/1600/40. would not start up, showing low battery alarm. bmv voltage was 25.33v soc 100%. 25.33v at inverta terminals. the first time it did this we waited a while then fired up. today would not fire up. i connected jenny for about 30 seconds then when turned inverta on all ok..

i have 4x s290 rolls battery's @ 24v. 230 ah fully charged 25.2v. i dont know if dc input low restart affects this but it is set to 25.4 v lowest setting?

allso the relay light is on, it has allways been on according to manuel this is an alarm pree a larm warning. but how do you know for what?



Multiplus-IIlow battery warning
7 comments
2 |3000 characters needed characters left characters exceeded

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Hi, I have a similar problem. Off-Grid MultiPlus II 3000, CCGX , 150/35 MPPT and a US3000 Pylon. Firmware 461 on Multi, latest firmware on CCGX and MPPT, Bus cable between CCGX and Pylon. Configured the Multi to the Victron Pylon Manual @ 51V DC input low restart (https://www.victronenergy.com/live/battery_compatibility:pylontech_phantom , section 4.3) but it does not auto restart after battery ran flat and and recharged. Only way i could get it to restart was to shut off the battery, wait for Multi to pick up voltage from MPPT and go into inverter mode and then switch the battery back on. Like Robin, i would like to know if it is not supposed to auto-restart after this voltage was recharged? I am about to change this voltage to 46 as per recommendation on this post , but want to know will this auto-restart the Multi. Kind regards, Schalk

Hi Schalk,

Please note that the 51 volt restart value was incorrect in the manual, I changed it a couple of days ago.

As these batteries are mostly used in combination with the ESS assistant (which overrides these values), this mistake was not found before.




Schalk van der Merwe avatar image Schalk van der Merwe Daniël Boekel (Victron Energy Staff) ♦♦ ·

Hi Daniel

I noticed that when i quoted the link, but was not sure if i made a mistake. pheew

Would you please be so kind as to comment on original question: is the unit supposed to restart once the voltage is met, or do one have to manually restart it, please?

Yes it should restart when low voltage condition is gone (like when charged with MPPT's)

Hi Robin.

"i have 4x s290 rolls battery's @ 24v. 230 ah fully charged 25.2v."

You might need to review you charging voltages and regime.https://www.solargain.ca/Rolls_Battery_Manual.pdf


Hi reviewd rolls Manuel again. 25.2v is correct. 2.1 v per cell. I had set the inverta to shut down at 23.4 as recommended in rolls Manuel. Which ment multiplus software automatically puts in 25.4v DC low restart figure. I have now had to change it to 21.v low shut down to get a low restart value of 23.0v way below what rolls recomended.

Hi Robin,

You might need to tell us what your bulk voltage is set to, and how long the batts are held in absorption, as well as the float voltage.

1 Answer
robin avatar image
robin answered ·

Hi. Bulk is 30v as per rolls manuel. Max absorbtion time is 4hrs. Actual calculation should be 4.2 hrs using rolls formulae.

Problem is with setting dc low shut down value, the dc low restart value automatically changes.

I have now set dc input low shut down value at 21.v . Making low restart value 23v (Rolls recomended 22.2-23.4 low voltage disconnect) I do not let system drop below 24v, just my rule. So all is working ok for us as the system is only on when we are around but for other people this may be moore of a problem if there trying to set victron equipment up to other manufacturers recomended settings.


2 comments
2 |3000 characters needed characters left characters exceeded

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

Hi @Robin,

A change is planned to allow adjustment of this 2V hysteresis value in the future.

robin avatar image robin Guy Stewart (Victron Community Manager) ♦♦ ·

thanks Guy