question

piet-hein-van-asselen avatar image
piet-hein-van-asselen asked

SmartLifepo4 with external temp sensor?

Goodmorning,


Whil i have a system with 2 x smart lifepo4 (Victron) and VE BUS BMS V2, Cerbo and Multiplus-II 12-3000 i am wondering about following:

I have DVCC enabled, so Cerbo uses BMS info for controll of charging, depending on voltage, current and temp info of BMS. I cant see temperature via BMS on Cerbo because Victron doesnt support this. I can add an external temp. sensor to overcome this.

Which temperature sensor will DVCC use for charging? Is it smart to add the external one? Doenst the system get "confused" ? What other problems might i expect?


Thanks in advance!


cerbo gxBMSTemperature SensorDVCC
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

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

5 Answers
Alexandra avatar image
Alexandra answered ·

@Piet Hein van Asselen

In DVCC you can choose the temperature sensor to use.

Activate STS and choose the sensor you want for control.

2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

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

heinzie avatar image
heinzie answered ·

Thanks for your replay.


I am adware of that but am wondering if that is the best way for the charging to use the external sensor instead of let the charging use the bms temp info?


Thanks in advance


1 comment
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

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

piet-hein-van-asselen avatar image piet-hein-van-asselen commented ·
small kick


0 Likes 0 ·
delf67 avatar image
delf67 answered ·

Why would overriding the temperature sensor built into the battery with a thrid party external one seem like a good idea?

1 comment
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

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

piet-hein-van-asselen avatar image piet-hein-van-asselen commented ·
Thanks for your reply.



Well first of all, i cant see the temeprature of the built in sensor because Victron does not support this at the moment. Second, as mentioned in my opening post, i would like to see the battery temperature in my Cerbo. 3rd, i have no idea if i connect the external sensor to the mulitplus or cerbo, if the charger uses that one OR the internal one. For over and under temperature expect the BMS works with the built in sensor for safety.

Also, if i connect the external sensor i can select wich sensor DVCC uses for charging purposes. But i can select AUTO, NO SENSOR, or the EXTERNAL SENSOR. If i selct auot, nothing is been displayed when i check wich one it uses. Same as when i check wich BMS it should use. Just because Victron doesnt suport it's own devices in the read out...


0 Likes 0 ·
pwfarnell avatar image
pwfarnell answered ·

The temperature sensor in the battery does not communicate the temperature to the VE Bus BMS. The battery has a low temperature setting to decide if charging is allowed or not and the battery tells the BMS if charging is allowed or not and the BMS then controls the chargers. If you add an external temperature sensor it will not be used to control the chargers, those signals will still come from the battery via the BMS, but you will have some read out of the battery temperature.

Until Victron add something to the Cerbo so it can read the battery Bluetooth like it does with other third party Bluetooth devices, monitoring of its own lithium batteries will remain sadly lacking.

2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

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

heinzie avatar image
heinzie answered ·

That is clear. Thank you for that.

1 comment
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

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

klim8skeptic avatar image klim8skeptic ♦ commented ·
@Heinzie there is nothing preventing you from adding a temp sensor to the cerbo, and not including it under DVCC STS.

Let the LBS temp sensors protect the batteries, and monitor the batt temps via the Cerbo.


1 Like 1 ·