Multiplus Charging LiFpo4 Below 5C - DVCC and Renew enabled.

Question

question

badwolf asked Jan 14, '24

Multiplus Charging LiFpo4 Below 5C - DVCC and Renew enabled.

We are in a bit of a cold snap and my batteries are getting down to 0C or below, and i've got my multiplus set to stop charging at 5C(41F) but it doesn't seem to work.

I even pulled my VE config via VRM to make sure its the same as what i setup via USB. Both my battery bluetooth app and my remote console are showing the same charge going into the batteries. (its not as much now that its at the sustain 13.3v)

I have DVCC setup, with temperature sharing and the mutli plus is showing the battery temp at 1C(34F)

What else do i need to check?

battery charging multiplus ve.bus DVCC

ss-2024-01-14-at-54402-am.png (214.8 KiB)

ss-2024-01-14-at-53756-am.png (105.1 KiB)

ss-2024-01-14-at-55149-am.png (69.8 KiB)

2

2 |3000

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

jjduke commented · Jan 14 at 03:37 PM

With DVCC on, wouldn’t the BMS be controlling the “Allow to charge?” You don’t say what battery you have but when DVCC is controlling charging info and charge sources…the Multiplus config is ignored. (the Ext. control” on the inverter in the cerbo display shows that this is what the Cerbo thinks is controlling the Multiplus)

If your battery BMS has no low temperature charging control, you should turn off DVCC because otherwise, you have nothing controlling low temperature charging and will damage your batteries.

Edit: Someone may know for sure, but I don’t believe the shared temperature can tell a BMS to not charge if the BMS has no algorithm to use the low temp “do not charge” function in the first place however, without dvcc, the Multiplus can stop the charging

0 ·

badwolf jjduke commented · Jan 14 at 10:11 PM

If i turn off DVCC i cant share the battery temp with my multiplus and mppt. I really hope that Victron didn’t set it up that way but that would explain it.

if thats the case then i wasted money on getting batteries that would talk to the Victron system.

0 ·

Modifications Space

Node Red Space

Answer 1 · 2024-01-14T14:26:35Z

Alexandra answered · Jan 14 at 02:26 PM

@BadWolf

Is the battery reading a shunt reading or a guestimate from the ve bus?

If not Check with a DMM with amp reading to see if that is actually what is happening.

1

2 |3000

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

badwolf commented · Jan 14 at 10:06 PM

My batteries bms connects to cerbo, they supply the voltage/current/temp.

My shunt is now on my ground to measure my DC-Dc charging.

0 ·

question