How to: relay and heating element, but with battery pack

I’m trying to follow the tutorial here (http://www.espruino.com/Heater+Controller), as it does exactly what I need. However, I need to run this off a battery pack rather than a 5V DC wall adapter.

My first thought was to use a battery pack of 4 AA batteries, generating 6V.

As I learned in another thread, apparently diodes can be used to knock down voltage. I presume one of those will come into play.

How can I adapt the tutorial to use a 6V power supply rather than a 5V?

Thanks.

You should be fine with the 6v.

I agree - the 6v should be fine for the relays.

Great, thanks guys.

I'm about done building it, and I realized that the power from the battery pack appears to just go to the light bulb.

What is the best way to power the Espruino off of the 6V battery pack as well?

I think the best way would be using the little battery header with one of these http://www.adafruit.com/products/261 (verified to match the header on the Espruino)

Per http://www.espruino.com/EspruinoBoard you can go up to 15v on the battery header. This will also bring vbat up to that level (so make sure you don't have anything that can't take 6v connected to vbat). You can safely connect USB in this state - the espruino has a diode in series with the +5v.

So, probably splice in here and connect that to the battery header?

1 Attachment

Yup.