Explanation on SIM Card redundancy



I’ve a router MAX BR1 mini , with 2 SIM card . I would like to understand the menu cellular setting and more specifically the
sub menu “Fallback to Preferred SIM when” what is the purpose of these options ? how can I use it ?
Could you explain to me in detail how is working exactly the switching of SIM card from A to B and vice versa ?

I found nowhere the explanation .

Thanks a lot



This gives you the option to select the “preferred” SIM - perhaps one of SIMS has a better signal quality / strength than the other, or perhaps the cost of the data is cheaper. However, when your preferred SIM stops working (mast issue, or perhaps it has used all of the allocated monthly data allowance), the back-up SIM (non-preferred SIM) will then start working - assuming it is able to connect to the mast, etc. There will be a short period of down-time whilst the 2nd SIM establishes a connection.

The fail-back informs the device when to try to use the preferred SIM again - when the device is idle for 3 minutes (as an example).

This works really well when you use a health-check option, like the one below.

Hope this helps,



After 60mins does it knock out connection while it tries the preferred sim? I’d like to not have it keep flapping back and forth checking when preferred sim is live again.


Hi @tfeerst,

Yes, with the settings above, it would “knock out” the non-preferred SIM whilst it tries to establish a connection using the preferred SIM. However, you can remove that tick and use Device is Idle setting - set the timer. If no traffic passes through the device for the stated period of time, it will try to connect using the preferred SIM.

Hope this helps,