Go Down

Topic: Fingerprint reader to open electric strike (Read 5 times) previous topic - next topic

charlescarver

Yeah I saw those. I'm a little weary of DinoDirect... those are rated for a 200mA current, does that mean that the DC wall power needs to be 200mA? I realize that's a terribly basic question, but I'm wondering if there's any room for a higher or lower current.

PaulS

Quote
but I'm wondering if there's any room for a higher or lower current.

Current is pulled by a device. The power supply for that device has to be able to supply, at a minimum, the current required by that device. Otherwise, the device may not work properly.

Think of a car starter and a weak battery.

Having a 500A power supply for a 200mA device is not a problem. Well, affording one might be, but using one won't be.

charlescarver

That makes sense, and will make my life a lot easier.

Would it be superfluous to use an SPDT Relay in this?

PaulS

Quote
Would it be superfluous to use an SPDT Relay in this?

A single pole double throw relay combines a normally closed path and a normally open path in one relay. Activating the relay opens one circuit and closes another. Do you need both?

charlescarver

Personally, I thought the setup above was fine. But I read about them and I felt like they would work well because the strike itself includes one, I'm assuming, but then I thought that since it included one it would be pointless for another.

Go Up