12 volt door latch wiring

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As I see it, a spring loaded or gravity operated door or cover could be "trip" operated by a basic solenoid but how do you close it again or is this not necessary?
Perhaps all the feed is gone so no need?
If closing is necessary, then a windscreen wiper motor/gearbox would be one alternative.
Battery driven (car battery) which would also drive any timer/relay module and limit switch arrangement.
Don't know about your choice of solenoid but if you have some basic design ideas and some detail of the solenoid then that would be a good start to getting some further help.
Battery power being present, no need for wind up timers. Plenty of economical electronic alternatives are available.

 

With your choice of latch, it would depend on how you intend to rig up the rest of the mechanism and how much "load" there would be on the latch.
The one shown has around 12w of power ( 12v x 1A) which is not a lot really.
Latch has only so much pulling power and under normal use ( door latch) there would be next to zero load.
i.e.latch operates the armature ( connected to the wedge bit) allowing door to open.

There are ways to make your latch operate at a mechanical advantage but beyond the scope of discussion here I believe.
Think along the lines of how the old mouse traps used to work.

 

Think along the lines of a DOOR catch - the type that (if you look closely) has one edge flat and the other 'curved' (to allow the door catch to close).

Add a solenoid to a catch of this type and, using a ONE-SHOT (monostable) circuit, the solenoid will pull for the 'period of the one-shot' and allow the door to drop open.

You may need a small spring behind the door to give the door a push and help it drop but that depends on how you make it.

A simple timer (plug-in if you have access to mains supplies at the feeding place?) powering a mains-powered one-shot timer (can be bought as ready-made module) is the easy way.

If you are limited to battery power you could purchase a monostable/timer that operates from 12V from many eBay suppliers (inevitably located in China) to achieve the same result.

 

Ebay.... See if I can link you to one.
What is the readout for?

 

Multi-purpose unit here.....this is an Aus site but should be available anywhere in Ebay.

https://www.ebay.com.au/itm/Digital-LED-Infinite-Cycle-Loop-Delay-Timing-Switch-ON-OFF-Relay-Timer-Module/112439920682?hash=item1a2df1082a:m:mi4wzCdMQFz8atu5Pq5ywUQ&var=412830497925&_sacat=0&_nkw=+timer+module&_from=R40&rt=nc&_trksid=p2334524.m570.l1313.TR2.TRC0.A0.H0.X+timer+module.TRS0&LH_TitleDesc=0|0

Scroll down the page and see connections.....your application would be as in the third photo.
(module control DC load diagram 2)

Don't be concerned about the trigger switch shown as it will not be used in yours.
(maybe...maybe not...see last note)

Programming...well, you may have to round up one of the kids.
(4 years and older usually works for me)

Can be a little confusing at first BUT yours should be P4 under Function introduction

I would be inclined to add a power switch or simply disconnect the power when not used.

Then down to Use Operating Instructions where you will need to follow through to step 8.

Note:- Looking at the unit further I think maybe settings are lost when powered down so may have to look at the "trigger" option instead.

When ordering remember to select the 12v dc version.