each coil uses 150mA
if you use the Arduino power, you may have a dip in voltage.
however, there is a away to trickle charge a cap to use that for the power dump to the coil.
you cannot change state before it charges, and you cannot energize two at the same time unless you size the caps properly.
Thanks for the reply. But I am not exactly sure what you mean.
The option is to have latching relays all around my house, which is powered through cabling in the wall.
I had a thought that I could have a main 15v 3-4A power supply fed throughout the house via phone cabling (to account for voltage drop), it should drop down to an acceptable 6-12 V by the time it hits the arduinos. I would then use the regulated 5v supply to latch the relays. If I cant power from the nanos, i basically have two options.
Option 1: Input wall cavity power sockets and then use AC - DC 5v 1A USB sockets which I plug into the nanos and then a separate 5v supply for the relays
or
Option 2: Send a higher voltage through the phone cabling all around the house and then attempt to regulate the voltage down to 5v at the end for the relay...Not sure on that one.
Any guidance would be very much appreciated. thank you in advance
Continue with the 330R. Current is only drawn as long as the relays are triggered.
It may be possible to drive the relays from the Arduino 5V, but only with big caps (>=1000µF) added, or you risk controller resets or other malfunction. But if you already have a 5V supply, you can power both the Arduino and relays from that supply.
Does this mean I can do either the main external power supply for everything through phone cabling or a single 5v in each wall as said above and then I activate a plus and a negative on a board such as this:
http://www.ebay.com.au/itm/Protoboard-Plus-Tiny-Premium-DIY-Protoboard-Perfboard-for-Arduino-AVR-PIC-/331627685381?hash=item4d368ce605:g:m5YAAOSwT6pVzF6S
and this would be an acceptable method of powering both units?
Thankyou for your time