Reversing Polarity on a Solenoid

[davisgraveyard]

I am using several 12V solenoid's with  Prop-1 to create a russling in the bushes effect.  The solenoids are car power lock actuators.   I want to to be able to throw the arm all the way out and then pull it back.  In a previous thread you posted a diagram for doing this with a motor.    
http://www.efx-tek.com/php/smf/index.php?topic=653.msg3466#msg3466

The actuator isn't really a solenoid as much as a geared motor that thrusts a piston foward as long as power is applied or pulls the piston if the polarity is reversed.

http://cgi.ebay.com/ebaymotors/Universal-Power-Door-Lock-Actuator-Car-Auto-BEST-DEAL_W0QQcmdZViewItemQQ_trksidZp3286Q2ec0Q2em14QQhashZitem563504aa92QQitemZ370256685714QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

So my question is can I use a simple sealed relay like this one from all electronics
http://www.allelectronics.com/make-a-store/item/RLY-516/MINIATURE-12-VDC-RELAY/1.html  

to swap the polarity?  ANd if I am going to operate several of these randomly one at a time can I use just one relay that works for all of them?

Or is there are better product  you can recomend?

[JonnyMac]

You need to check the current rating on the device; that small relay is only good for 1A and that may not be sufficient.  As ever, you need to use two relays for reversing: one relay controls the direction of current flow through the coil (or motor) and the other provides on/off control.  If you find a good DPDT relay you can use it for both operations; the on/off relay will just use the COM and N.O. contacts on one side of the relay.

[davisgraveyard]

The 12VDC power supply I am using to power these is 1.5A.    But I wonder if I shouldn't just use the dual releays that are for cars like this one  http://www.allelectronics.com/make-a-store/item/RLY-525/DUAL-12-VDC-RELAYS-DOOR-LOCK-RELAY-/1.html

It's rated at 5-10A but it is wired to do what I want.  I think they even sell the 6 wire harness for it too.   Now I will just have to figure out how to wire it up? 

Am I going to need one of these for each actuator or can I wire this in a way with the Prop1 that I can use it with several of these that I operate one at a time?

[JonnyMac]

Great find, Jeff -- I have to share this with a [pro] customer in Kentucky as we were just going through the whole reversing thing the other night.  The elegance of this setup shows I'm not as good with relays as I am with digital electronics.  The way the relays are wired forms what we call an Exclusive OR gate; when one relay OR the other is active -- but NOT both -- current will flow through the external device (terminals B and E). 

I believe you're going to need one per relay module per device, and two outputs to control direction of current, wired like this:

I believe you will need one relay pack and two outputs per device you want to [independently] control.

[davisgraveyard]

You sure there isn't a way I could wire this thing so I used the single pair of relays to toggle all 7 actuators and use OUT1-7 to toggle which actuator was live and OUT0 would toggle the actuators direction?

[JonnyMac]

Yes, I'm quite sure.  That said... I've been wrong in the past so if you come up with a solution that is escaping me I'd love to see it.