Alternative Power Supply

Hello Guys,

I'm very new in Electronics and arduino.

I have a sensors which works with a pile ER14250 ( This sensor is close to a 230V power supply.

So I want to use that one for my sensor. I thought to use this adaptator : RAC03-3.3SC (

Do you think it is enought or not ?

Please advice.

Kind Regards

Depends on the sensor and it's min voltage requirement, it certainly supplies enough current...

So what sensor? Is it 3.3v compatible?

Thanks to answer.

The sensor is a Fibaro Door/Window Sensor ( which is a 3.6V.

This is only information I have.


If the battery lasts for 2 years, the current consumption must be in the range uA, the powersupply can give almost 1 A.
The powersupply can give 1000000 times more than needed

So I can't use it ? I don't really understand your answer ^^ ^^

If I use this one : AC/DC 3.3 V/DC 300 mA 1 W Recom International RAC01-3.3SC, is it possible to plug it to my sensor with another adaptor or something like that ?

I really want to escape using battery.


With your first adapter you can connect about 1000000 window sensors. It's a little bit overkill.
(Second adapter 300000)

Why not use batteries if they last for 2 years, if you have a power failure you do not have any alarm.
After you have had a power failure you can get an alarm same as battery change.

Door/Window Sensor's battery life is up to 2 years, on default settings.
Current battery level is displayed in the Home Center 2 configuration interface. If a battery icon turns red, it means the battery needs replacement. In order not to trigger an alarm when replacing the battery, II-nd association group must be deleted and the Sensor's configuration must be changed to default, prior to the battery change.


Thanks for your answer.

I want to use a power supply because as I can read on some forum, that sensor consumes lot of battery. Some people says after 3 month battery was down !!

In fact, if I can avoid bettery it will be better for maintenance :slight_smile:

If I understand, I can use the adapter I mentioned but it is overskill regarding my sensor, Am I correct ? :slight_smile:


3.6v well 3.3v should do the job… you should be ok…

Thanks :slight_smile:

The sensor probably consumes 10's of mA, not uA, but does so for a few ms every so often.
The average current is low, doesn't imply the maximum current is that low.

The original battery is lithium thionyl-chloride which have a very long shelf life and
good performance at low temperatures (but contain thionyl chloride which is an
extremely caustic chemical, note the wikipedia entry comment:

High cost and safety concerns limit use in civilian applications. Can explode when shorted. Underwriters Laboratories require trained technician for replacement of these batteries. Hazardous waste, Class 9 Hazmat shipment.[5]

In fact, if I can avoid battery it will be better for maintenance :slight_smile:

Almost always the case. Unless your concern is to operate through mains failures, batteries are the "weakest link" in the project.

If of course it is for an alarm and you wish to take care of the contingency that and intruder cuts the mains, then you want one central battery, generally a 12V gel cell (or upmarket; lithium ion). Obviously since your alarm cannot operate without the central control unit, it makes sense to use that same central battery for all functions.