# How to read BMS/Multiplus values using API, ModbusTCP or MQTT

**URL:** <https://community.victronenergy.com/t/how-to-read-bms-multiplus-values-using-api-modbustcp-or-mqtt/56392>\
**Category:** Modifications\
**Tags:** multiplus\_2\_gx, professional, vrm\
**Created:** [12 April 2026 10:05 UTC](https://community.victronenergy.com/t/how-to-read-bms-multiplus-values-using-api-modbustcp-or-mqtt/56392 "2026-04-12T10:05:05Z")\
**Posts on this page:** 6\
**Page:** 1

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**Author:** ![TulipanoBatterij](https://avatars.discourse-cdn.com/v4/letter/t/d26b3c/32.png) [@TulipanoBatterij](https://community.victronenergy.com/u/TulipanoBatterij)\
**Post date:** [12 April 2026 10:05 UTC](https://community.victronenergy.com/t/how-to-read-bms-multiplus-values-using-api-modbustcp-or-mqtt/56392/1 "2026-04-12T10:05:05Z")

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I use VRM API, ModbusTCP and MQTT.

I would like to read:

- Multiplus settings, such as Absorption voltage or Float voltage
- Battery/BMS statistical values, such as min/max cell voltage (which is available in the VRM as a Widget)

Regarding Multiplus settings; I want to read the values remotely (no MK3 cable) to investigate a system whether settings are correct and/or inadvertently changed. This would save a site-visit.

Regarding Battery/BMS, I can get the battery voltage and SOC, using the VRM-API/stats with attributes bv and bs, but I cannot find the correct attributes for min/max cell voltage. The closest I find (VRM-API/attributes) are 173/mcV for Minimum cell voltage and 174/McV for Maximum cell voltage, but the VRM stats-API does not return information.

Suggestions more than welcome!

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**Author:** ![nickdb](https://dub1.discourse-cdn.com/victron/user_avatar/community.victronenergy.com/nickdb/32/51440_2.png) [@nickdb](https://community.victronenergy.com/u/nickdb)\
**Post date:** [12 April 2026 10:07 UTC](https://community.victronenergy.com/t/how-to-read-bms-multiplus-values-using-api-modbustcp-or-mqtt/56392/2 "2026-04-12T10:07:19Z")

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These are mostly all available from the GX via MQTT.  
Go download the [modbus](https://www.victronenergy.com/live/ccgx:modbustcp_faq) register from the victron git page, just google it.  
Nodered is also a preferred way of doing this - refer to the dedicated nodered section in this forum.

The multiplus basic settings and assistants are typically only configurable via a mk3 or remote veconfigure.

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**Author:** ![TulipanoBatterij](https://avatars.discourse-cdn.com/v4/letter/t/d26b3c/32.png) [@TulipanoBatterij](https://community.victronenergy.com/u/TulipanoBatterij)\
**Post date:** [13 April 2026 12:23 UTC](https://community.victronenergy.com/t/how-to-read-bms-multiplus-values-using-api-modbustcp-or-mqtt/56392/3 "2026-04-13T12:23:08Z")

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> [@nickdb](#):
>
> Go download the [modbus](https://www.victronenergy.com/live/ccgx:modbustcp_faq) register from the victron git page, just google it.

Yes, I did find the register (CCGX-Modbus-TCP-register-list-3.71.xlsx) but did not find the Absorption/float values.

Using MQ Explorer I did not find those settings either.

If you know the register values, please let me know.

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**Author:** ![nickdb](https://dub1.discourse-cdn.com/victron/user_avatar/community.victronenergy.com/nickdb/32/51440_2.png) [@nickdb](https://community.victronenergy.com/u/nickdb)\
**Post date:** [13 April 2026 12:31 UTC](https://community.victronenergy.com/t/how-to-read-bms-multiplus-values-using-api-modbustcp-or-mqtt/56392/4 "2026-04-13T12:31:16Z")

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I don’t believe the internal settings can be accessed like that.

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<div class="post-metadata">

**Author:** ![TulipanoBatterij](https://avatars.discourse-cdn.com/v4/letter/t/d26b3c/32.png) [@TulipanoBatterij](https://community.victronenergy.com/u/TulipanoBatterij)\
**Post date:** [13 April 2026 13:25 UTC](https://community.victronenergy.com/t/how-to-read-bms-multiplus-values-using-api-modbustcp-or-mqtt/56392/5 "2026-04-13T13:25:03Z")

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Thanks

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<div class="post-metadata">

**Author:** ![system](https://europe1.discourse-cdn.com/victron/original/1X/21a9a7b5db7c6339715f993568736a7053199995.png) [@system](https://community.victronenergy.com/u/system)\
**Post date:** [27 April 2026 13:25 UTC](https://community.victronenergy.com/t/how-to-read-bms-multiplus-values-using-api-modbustcp-or-mqtt/56392/6 "2026-04-27T13:25:31Z")

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Closed on 27 April 2026 13:25 UTC

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