question

jorge-folgado avatar image

Sustain current too high?

Hello Victron fellows,


I have set some Li ion with Victron inverters, always for self consumption with PV inverters, but this one is cracking me up. This system consists in three 48V Multiplus II 3000/35 as a three phasic system, and an ESS assistant is set. The sustain voltage is 43V and cuttoff around 42V. The modules have a low SOH, but the system should work anyway. It charges and discharges correctly, up to the point where my BMS disables allow to discharge at around 48V, because there are low cells (it should discharge to less than 42V if it was good).

Then, Sustain mode is active and the current goes UP TO 90A. Of course when this happens the voltage raises quickly, the allow to discharge comes on again and it goes to Discharging mode. Repeating the process endlessly - Even without PV POWER, that means it consumes a lot of power.

My question is, why does it go up to 90A, since sustain mode should be 5A per unit and how can I solve this?

Thank you very much!

Multiplus-IIESScurrent limitcharge current limit
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.

2 Answers
Daniël Boekel (Victron Energy Staff) avatar image
Daniël Boekel (Victron Energy Staff) answered ·

Hi @Jorge Folgado

I've sent you an email, we'd like to look in to this.

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.

diego-quintero avatar image
diego-quintero answered ·

I Have a similar problem, can you provide some guide?

I connected the batteries switch on Multiplus Victron, I have installed ESS too and then 15Amps was putted in the system, when I only allow 3 max in the configuration. In my system this can damage my batteries. After 10 min I switch everything off, because sustain mode was present and could not have control with ESS grid set point.

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.