Looking for a SS Latch type relay.

Other Hardware General Electronics
1

Ultimate newb alert

I have just started getting into Electronics and for my first real project, I'm working on a system to monitor moisture levels and automatically water just those pots that need water.

I "think" I have the basic logic of how to do what I want to do worked out, but I'm really shy on knowledge of what parts I'm going to need or how to use them, but I'm experimenting and learning.

My main need right now is some form of "Latching" relay to control a valve in some manner. My idea is that once I know which pots need watering, I open the required valves then turn on the pump to get the water flowing. Then after a period of time turn off the pump and close the valves.

Because I want to control many valves with a minimum of pins (I think I have the multiplexing part already figured out) I will need the latching behaviour so I can change the state of a valve then move on to the next one and know it will keep it's state without the need to apply continuous power (or ground).

Can anyone recommend something that will work. I'm not sure of voltages required or what I'm using to open/close the valve yet. At this point even just something to experiment with turning a LED on and off will be acceptable.

Thank you in advance.

2

The Arduino outputs latch, so, as long as the arduino is active, whatever is connected is latched, too. If that's what you're angling at.
If you are contemplating lots and lots of outputs and/or economising on I/O pins: http://www.arduino.cc/en/Tutorial/ShiftOut

3

The point of latching relays is that you only need a supply capable of driving one relay, so long as you do one at a time - with non-latching relays the supply needs to handle all N relays simultaneously... Do they make latching solenoid valves?

4

MarkT:
The point of latching relays is that you only need a supply capable of driving one relay, so long as you do one at a time - with non-latching relays the supply needs to handle all N relays simultaneously... Do they make latching solenoid valves?

Thanks, that looks like it might work for what I need. It will change my control logic a bit, but I should be able to handle that.

Now to order some and see what happens. Worse case I have another few $ worth of parts to add to my inventory.

Thanks again.