WSN power source selection

[Garrett Cook]

Page 11 of the WSN-3212 guide states:

"The device automatically detects which power source is connected and switches to that source. The device is not designed to provide battery backup in the event of loss of external power. If both are connected, the device functions from the external power input, but may require a device reset when external power is disconnected."

I see the phrase "MAY require a reset" as implying that it might or might not.  Is it possible, but not guaranteed, that the node will continue running (albeit on AA battery power) even after AC is disconnected?

Thanks,

Garrett

[Kevin_H · Accepted solution]

Hey Garrett,

As the manual states, the product was not designed for battery backup.  In the case you described, the node will most likely reboot.  When the external power is removed, the voltage will momentarily drop causing the node to reboot itself.  There is a chance the node will seamlessly transition, but it is not guaranteed and I would not recommend on designing your system for this.

Let me know if you have any other questions!

Kevin

[Garrett Cook]

If the node resets, is that an automatic thing, or does someone have to go physically visit the node and get it going again?

Garrett

[Kevin_H]

Hey Garrett,

The node automatically resets on its own when the power drops.

Kevin

[Garrett Cook]

I see.  So it seems that even though we wouldn't necessarily rely on this happening, then it is at least possible that the node would reset when the external power is cut off, and then begin functioning on battery power, if AAs are installed.

Also, the manual states to use only alkaline AA batteries...are lithium (non-rechargable) AA batteries able to be used?

Thanks!

Garrett

[Kevin_H]

We recommend using alkaline batteries, and all of the power specs are based on that type of battery at room temperature, but lithium AA batteries will work as well.

Kevin