Medeco Switch Locks.

[Dak]

Just bought 10 medeco switch locks off ebay for $10. I had no idea what a switch lock was, but 10 medecos for $10 seemed like a good idea to me. They just arrived today, each with two keys. Now, maybe I dont know how a switch lock works, but the keys don't turn. So is that suposed to be the case, or have I just recieved a bunch of bogus keys. I certainly hope its the latter.

I know these locks are for electrical applications, but hopefully this can be answered.

[Solomon]

I was wondering who won that auction! We were talking about this the other day and someone said the keys didn't look like the cuts were angled, do they look ok to you?

[Dak]

well there were several of those auctions actually. All by the same person.

All the keys have the angled cuts, although the cuts themselves arent too terribly complicated.

[Dak]

found out why the locks wouldn't turn. I just wasnt turning the key hard enough . I still have a question though. What do these locks do electrically?

[Evan]

found out why the locks wouldn't turn. I just wasnt turning the key hard enough . I still have a question though. What do these locks do electrically?

Could be anything from SPST to more than that...

Are there two key pull positions or only one ?

Other options are maintained contact and momentary contact...

~~ Evan

[Dak]

Could be anything from SPST to more than that...

Are there two key pull positions or only one ?

Other options are maintained contact and momentary contact...

~~ Evan

one key position. What is SPST?

[JK_the_CJer]

Could be anything from SPST to more than that...

Are there two key pull positions or only one ?

Other options are maintained contact and momentary contact...

~~ Evan

one key position. What is SPST?

Single-pole single-throw. It means that the switch either allows current to pass through one path or not; like a normal light switch.

SPDT lets current be directed to one of two places depending on the position of the switch. DP*T is where two switches are mechanically linked together.

[straightpick]

All the Medeco switchlocks SPDT (single pole double throw). They come in momentary contact (the key will spring back if you turn it and then release the key), key removable in one position or two positions. There are 3 pins on the back of the switch. When you hold it by the flat sides facing you ( keyway in correct position) the pin on the left is the common terminal (C), the center pin is normally open (NO) and the right pin is normally closed (NC).

[Dak]

...a little over my head there

So these locks can used to turn something on provided it only needs electric current temporarily to start before it can sustain itself? maybe like an engine or something?

[Velvokay]

Ok, so if your switch-lock has 3 terminals, one is a common, or negative terminal depending on the circuit. One metal terminal on the bottom(red in my diagram) is always connected So in any of the 2 positions, one terminal is off the other is on. It takes no power. here is a simpler drawing position1 - /- position 2 think of the slash as the common terminal,in one position current can flow through the right side only and in the other position current will only flow through through the left. the common terminal is never interrupted. say you have a battery and 2 light bulbs. you hook up the positive side to the common. and the positive terminal of a light to one of the other terminals , and you do the sam with the other. In one position one light will go on, and in the other position the other light will be on. So one of the two lights will always be on.

[Dak]

Wow. Thank you very much. I understand now. It just switches current from one circuit to the other hence "switch" lock. Thats a very understandable explanation thanks. I might actually use these locks for something other then picking now.

[Equality]

I too grabbed ten of these from ebay, and have been having fun messing with them for a bit in some circuits, but wondered if anyone knows if there is a way to disassemble the cylinder to remove some of the pins.

These take a lot of tension to turn even with the proper key as you found out, I'm planning to see if there's a removable spring or anything that might make exploring the lock a little easier.

[MacGyver101]

I might actually use these locks for something other then picking now.

It probably goes without saying, and I'm not sure what uses you might have actually been thinking of... but the Medeco switch locks are usually rated such that they could be used with standard household voltage, but not to the full current load of a household circuit. (The standard "65 Series" switches are only rated to 7 amps at 125/250VAC, for example.)

So... you can use them for many applications, but don't try to directly switch the power to your garage door opener with them, or anything similar.

As I say... sorry if that's obvious advice: I just figured I'd rather mention it than read some unfortunate follow-up post next week.