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simple question

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Drcutnsplice

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I have three dresser drawers that I wish to lock. I'm using 3 - 12V 2A Cabinet Drawer electric magnetic lock, I want the ability to unlock each drawer separately and plan on using a DC 12V 4 channel remote control switch relay receiver 433 Mhz wireless RF Module. The 12v 2A electro magnetic relays are only momentarily switched on just to release the drawer, my power supply is a 12v 3A power supply will everything operate correctly? Is the power supply adequate.
 
will everything operate correctly? Is the power supply adequate.
Sounds like it should work fine.
You have as 50% margin for the power supply, which should be more than adequate.
 
Remember to place a diode (e.g. 1N400x) across each solenoid coil (cathode to positive) to suppress the inductive transient upon turn-off, which avoids burning/welding the relay contacts.
 
I want to ask another question concerning this application and didn't know if I should start a new thread. but Let's say I would like to get 12v to the drawers and drawers open and close so I don't want to use wires.I need the circuit to be energized on the drawer side only when the drawer is completely closed, when the drawer is completely closed there is an air gap. I'm looking for something to conduct through the air gap like a spring and brush would on a motor armature. What would that part be called and where can I find a manufacturer with a catalog of this item? I search for spring loaded contacts but don't see anything that I envision. I imagine a spring and a brush except the brush is made to stay in the holder so it doesn't fly out when opening the drawer and then a contact point on the other side of the air gap.
 
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Something like this:- https://uk.farnell.com/everett-char...spring-probe-pcb/dp/4577723?st=spring contact

They are designed for test rigs, but you could certainly put them to bridge the gap. That one is one of the larger ones, but I guess that you have plenty of space and robustness and longer travel are needed. That has 1/4" (6.35 mm) of travel. It will tend to push the drawer open (16 oz / 454g force) when fully compressed, but if the drawer is being latched closed that may not matter.
 
How about battery contact springs & plates?
Pairs of those are cheap, have a good tolerance on positioning and quite a range of compression, if fitted to the back of the drawer; eg.
**broken link removed**

Or, if the drawers are suitable, put brass strips along the drawers sides and contact wipers/brushes either side in the cabinet, on the back of the face.

Or if the drawers have telescopic metal runners, they may provide a connection?
 
There won't be any arcing unless there is current flowing when the contacts connect and disconnect. Though that might include if the lock is engaged when you open the drawer.

But let me propose an alternative.
If there's space for it, put the lock on the dresser frame behind or beneath the drawer and have it engage a hook on the drawer. That way, the wires to the lock don't move.
 
I'm with Chris. Always better to put the more complex parts of the system on the stationary parts of the structure.

Also, please post a link to information about the lock. I might need some for something else.

ak
 
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