Electrical question for power locks...

[My52Chebby]

I would like to be able to lock and unlock my power locks with ONE momentary switch.

For example:

Push momentary switch once = Doors lock

Push same momentary switch a second time = Doors unlock.

I've seen push button switches that are "latching", in other words, push the switch once = open, push switch again = closed. I need a momentary switch that "toggles" from Open to Open. Or maybe I need a latching relay that does that?

Any help would be greatly appreciated.

My52Chebby

[enjenjo]

most door lock actuators work by reversing the polarity. To do this you need a double pole, double throw switch, loaded to the off position. Wire as shown. Red is power, black is ground, blue and green are the actuator leads.

[My52Chebby]

... but I want to use a single pushbutton. This YouTube video does exactly what I need but the fellow doesn't explain how he accomplishes this.

His pushbutton, lights one light on the first push, a second light on the second push... No push = No light.

http://youtu.be/iNzIWwY2xzQ

Wish I knew what he did. How does one contact someone on YouTube?

My52Chebby

[Fat Cat]

... but I want to use a single pushbutton. This YouTube video does exactly what I need but the fellow doesn't explain how he accomplishes this.

His pushbutton, lights one light on the first push, a second light on the second push... No push = No light.

http://youtu.be/iNzIWwY2xzQ

Wish I knew what he did. How does one contact someone on YouTube?

My52Chebby

The concept being demonstrated in that video will not work with power door locks. All they are doing is essentially turning a light switch on and off.

What you need to do with power door locks is to reverse polarity on the actuator to change the lock state. So you need to make the positive the negative to reverse said state.

[Bruce Dorsi]

His pushbutton, lights one light on the first push, a second light on the second push... No push = No light.

http://youtu.be/iNzIWwY2xzQ

My52Chebby

That's not what I see in the video.

It appears one light is always ON.  ...Pushing the button turns the light OFF and the other light ON.

[My52Chebby]

You're right Bruce... I didn't catch that.

Thanks.

[Fat Cat]

His pushbutton, lights one light on the first push, a second light on the second push... No push = No light.

http://youtu.be/iNzIWwY2xzQ

My52Chebby

That's not what I see in the video.

It appears one light is always ON.  ...Pushing the button turns the light OFF and the other light ON.

That is because the relay has 2 circuits. One that is normally open and the other that is normally closed. If you were to remove the switch from the circuit one light would be on all the time as long as power were applied to the relay power input circuit.

The 5 contacts on that relay are

#30   = Accessory Power In
#87   = Accessory Power Out (Normally Open)
#87A = Accessory Power Out (Normally Closed)
#86   = Control Circuit Power
#85   = Control Circuit Ground


The difference between a latching relay and a normal relay is that you have to apply power constantly to the coil (85 & 86) to maintain the circuit and a latching relay only needs the switch circuit to be change the relays state.

[enjenjo]

You can so it with two of these  http://www.waytekwire.com/item/75533/SOLID-STATE-LATCHING-RELAY/  and a pushbutton.


Or you can do it with one of these  http://www.waytekwire.com/item/44141/SWITCH-RECTANGLE-ROCKER-BLACK/  and no relays. Push one end and it locks, push the other end and it unlocks.

[My52Chebby]

Last night I ordered a DPDT push button switch off the 'Bay...

That pb switch and this diagram using two regular relays should do it for me.



I'm thinking I'd just have to connect "lock" to one side of the DPDT switch and "unlock" to the other side. That way, when not pushing the switch, there would be no power to either the lock or unlock circuits.

Any thoughts?

My52Chebby

[Bruce Dorsi]

I think you may still have a problem.

What switch did you order?  

Assuming that MOMENTARY power is to be applied to the actuator, the switch needs to be a MOMENTARY switch with a N.O. (normally open) contact.

You mention hooking one side of the switch to "Lock" and the other side to "Unlock."  ....What other connections will be made to the switch?

Perhaps I am missing something obvious, but I don't understand how you can get a DPDT Pushbutton switch to work the way you want.

[My52Chebby]

... I'll have to wait until the push button switch actually arrives then I'll mock up a test circuit.

What I want to do may be impossible to do...

My52Chebby

[wayne petty]

start with this..

http://www.serelays.com/library/section7/105A_755.pdf

my brain is not awake enough to work thru relay logic..

but i think that you will need a momentary switch...

probably a single coil latching relay...

and a conventional power relay that supplies the contacts of the latching relay.. with the latching relay and the power relay both supplied with power to the coil from the momentary switch..

this way.. when you push the button.. the latching relay flips and the  contacts are actuated by the power relay.. when you release the momentary button.. the power relay cuts off and the latching relay just stays until the next impulse..
this prevents you from burning out your actuators by leaving power applied..

over the next few days.. i will dig thru the relay catalog pages and see if i can spot a latching or other relay that would work..

i did replace the 5 ford relays on a 63 tbird retractable convertible .. with i think 7 or 8 industrial relays to make the multiple screw motors.. panel swing motors , solenoids and one high volume top pump.. and it worked when i was done..
that car owner had been messing with it for years and years... when it was finally fixed.. he just sat and ran it back and forth after i left..  until he burned out the pump commutator.  it was an easy swap to a conventional sized displacement pump.. but it was a slow boat to china watching that top open and close..

on and i only cut one wire..  and that was one that was broken in the molded rubber socket anyway..

i did have to go into the relays and replace the braided copper wires with much thicker braid.. i used .. solder wick..

the tiny braid was just not up to it..