Hi all.. I'm thinking about working on a project that uses a microcontroller to run a motor that needs 12VDC at 1A max for about 30 seconds twice daily and will be in-use outside (it's for a pet door). The microcontroller I'm planning to use is a TI MSP430 based device (not sure of the exact part quite yet). In doing some reading earlier on this forum and elsewhere I gather I need to watch the coil resistance to ensure I don't overstress the μc's output port(s). Whatever relay is chosen, I'm leaning towards a type that will take the weather pretty well (meaning sealed from external exposure as much as possible).. I was thinking of a reed switch but cost is an issue as I'd like to keep it as low as possible. Any suggestions?
P.S. in poking around on mouser.com I see that most reed relays that I believe meet my criteria are about $10 or higher per relay. Hopefully I can find something for much less...?
Also -- if a relay is indicating a contact rating in AC volts only does that mean it's not usable for DC? I'd think it would work but the rating is just different -- is that a valid assumption? Thanks!!
P.S. in poking around on mouser.com I see that most reed relays that I believe meet my criteria are about $10 or higher per relay. Hopefully I can find something for much less...?
Also -- if a relay is indicating a contact rating in AC volts only does that mean it's not usable for DC? I'd think it would work but the rating is just different -- is that a valid assumption? Thanks!!