# Cerbo GX relay control of Smart BatteryProtect – officially supported?

**URL:** <https://community.victronenergy.com/t/cerbo-gx-relay-control-of-smart-batteryprotect-officially-supported/34727>\
**Category:** DIY\
**Tags:** battery\_protect, marine, cerbo\_gx, diy\
**Created:** [4 June 2025 22:42 UTC](https://community.victronenergy.com/t/cerbo-gx-relay-control-of-smart-batteryprotect-officially-supported/34727 "2025-06-04T22:42:21Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![stovelace](https://avatars.discourse-cdn.com/v4/letter/s/f6c823/32.png) [@stovelace](https://community.victronenergy.com/u/stovelace)\
**Post date:** [4 June 2025 22:42 UTC](https://community.victronenergy.com/t/cerbo-gx-relay-control-of-smart-batteryprotect-officially-supported/34727/1 "2025-06-04T22:42:21Z")

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Hi,

I’d like to confirm whether it’s technically correct and supported by Victron to control a Smart BatteryProtect 12/24V using the programmable relay output of the Cerbo GX.

The goal is to use the Cerbo GX to disconnect all charging sources (MPPTs, Orion, Phoenix Charger) by toggling the Smart BP’s Remote L input to ground via an external relay, controlled by the Cerbo’s relay. This would either happen when I turn my main battery switch OFF, or based on a condition (e.g. low voltage, low SoC, or similar).

My questions:

```
Is this setup officially supported or recommended by Victron?

Is it considered safe and correct from a design standpoint?

Are there any diagrams or best practices you can share for this use case?

```

Thanks for your help,  
Tom

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**Author:** ![owenb79](https://avatars.discourse-cdn.com/v4/letter/o/8baadc/32.png) [@owenb79](https://community.victronenergy.com/u/owenb79)\
**Post date:** [5 June 2025 05:10 UTC](https://community.victronenergy.com/t/cerbo-gx-relay-control-of-smart-batteryprotect-officially-supported/34727/2 "2025-06-05T05:10:53Z")

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It should work. The MPPTs won’t like it if the solar is still connected. You will have to disconnect the solar as well. If the voltage is low enough, you could install a 24V or 48V battery disconnect to disconnect the solar. The 24V will go up to 30V, and the 48V will go up to 60V.

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**Author:** ![pwfarnell](https://dub1.discourse-cdn.com/victron/user_avatar/community.victronenergy.com/pwfarnell/32/2341_2.png) [@pwfarnell](https://community.victronenergy.com/u/pwfarnell)\
**Post date:** [5 June 2025 05:42 UTC](https://community.victronenergy.com/t/cerbo-gx-relay-control-of-smart-batteryprotect-officially-supported/34727/3 "2025-06-05T05:42:31Z")

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You can control the SBP remote terminals directly by a cerbo relay as the remote terminals will have a low current draw. If you wish to drove an external relay be aware of the issues in this FAQ.

> [@Using inverter / MPPT / GX device programmable relays with higher current, inductive or capacitive loads](https://community.victronenergy.com/t/using-inverter-mppt-gx-device-programmable-relays-with-higher-current-inductive-or-capacitive-loads/99):
>
> Many Victron products have programmable relays included which can be used to send signals between each other or to control small loads. These ae typically rated as for the Cerbo GX as DC up to 30 VDC: 6 A DC up to 70 VDC: 1 A AC: 125 VAC: 6 A There have been many reports within the community from people who have burnt out the contacts or welded the contacts closed in the programmable relays in their systems. This is often caused by connecting the relays to inappropriate loads, sometimes loa…