"Electric Cabinet Lock (MA1208) is a compact and all-metal lock ideal for delivery locker, cabinets, drawers and steel furniture. Surface mounting either vertically or horizontally offers easy and flexible installation. The electric cabinet lock is compatible with any existing access control system or simply controlled through a remote keypad or key switch. The cabinet lock allows mechanical override for emergency open. Electric Cabinet Lock (MA1208) is energy saving, cost efficient, robust, easy to install and suitable for one or multiple cabinet applications".

Specification
Operation Voltage 12/24VDC intermittent ±10%

Power Consumption 12V DC 800mA

Operation Mode Fail Locked

Holding Force 150KG

Maximum power on time Less than 30 second

Solenoid Rated for intermittence use

Cycle Rating More than 1,000,000 times

Mechanical Override 7mm hole

Working Temperature -20ºC ~ +60ºC

Dimensions LxWxH 72mm*56mm*13.8mm

Gross Weight 250g

Protection Class IP20

Compliance CE and RoHs certificate

Looking at the above this thing can be powered using a simple 12 VDC 1.0 Amp wall wort. They also pretty clearly state "The electric cabinet lock is compatible with any existing access control system or simply controlled through a remote keypad or key switch". With that in mind wouldn't using a Raspberry Pi be overkill? Since a simple key switch can be used I would assume any dry contact closure will unlock it? Maybe I have that wrong? If you want to program a Raspberry Pi to accept a code from a key pad I can see where a micro controller will work but it looks like all you need based on the above is a dry contact closure with the thing powered from 12 VDC? Even if you used a cypher code as several have suggested, you really don't need much beyond an inexpensive uC and a few lines of code. What exactly is the plan for using a uC and why the delay?

Ron

The lock is rated for intermittent use, 30 seconds max at 12V; otherwise it gets dangerously hot. It's also a fail-secure lock which means when it has no-power it's locked (needs power to unlock and to stay unlocked). In applications such as a secure entrance with a pin pad, it's a simple 12V pulse for x seconds and done. I'll be using it on a scheduled system, where the door needs to be unlocked for several hours at a time. In order for the solenoid to move it needs a 12v pulse and then it only requires a small amount of voltage (6V) for the solenoid to remain seated (unlocked). The door lock will be controlled via WiFi, and the pi zero w works well for this.

 

That 6 V figure is for holding current. Why not measure the latching and holding currents and go from there. It might prolong the lifetime. It's already intermittently rated. If it's for house hold security.......one might look for other units. If you need a prolong open duration......power will have to be cut. Very poor design.

 

Hi

The 2N3906 really cant supply enough current to drive the solenoid without burning up.
A mosfet would be better driver.
You can do something like this. In the simulation shown, the power supply turns on after 1 sec. Q1 turns on and generates a pulse with a width set by R1/C1. The values shown apply 12 volts to the solenoid coil for about 500mS then drops to 6v. The value of R6 should be the same or close to the solenoid DC resistance and of appropriate wattage. The value would be 15ohm, 5W for the circuit shown.

eT