Electrician-type people, help me with a limit switch!

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I am sick and tired of the motion sensor switch on my safe. Half the time I have to wave my arms around like an idiot to get it to turn on. I used to have one with a limit switch that would turn on when you opened the door and off when you closed it. Simple.

However, as I try to find a decent limit switch, (has to be mini, micro or mini micro to fit) I find there is a lot of cheap crap out there! What is a reliable, well-built brand? One that will last a long time and not start a fire inside my safe! ;)

Thanks!
 
Where are you located in the state? Many options. None of the good ones are cheap.
 
Do you have a pictureof old limit switch or physical dimensions ? Is it 110 or low voltage? What did the other limit switch in? physical damage or burn out? I did have a bunch of different sizes for medical equipment. Maybe brand of safe and I can look at original specs.
 
Google Microswitch. That is a brand name but the search will find switches from many manufactures. Voltage doesn’t matter to a mechanical limit switch. Allied Electronics and Newark are two good sources.
 
You mean like what is in a refrigerator or washing machine? How are you planning on mounting it? Have you tried Grainger? I would also second the Newark recommendation, as they have pretty good selection filters on their Web site.

There used to be this place called Radio Shack, but I think all they have is cell phone cases.
 
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Ditto the recommendation for either McMaster or Graingers. Anything the McMaster sells is usually top quality
 
Unfortunately the old switch is still being used in the old safe that I sold and no old appliances lying around. It will be used on a 12v setup.

I will check out McMaster, Allied, Grainger and Newark.

These are the only pics I have left on my phone of the Patriot Safe Co. safe switch:
In some sort of housing mounted inside the safe (after new LEDs): [IMG2=JSON]{"data-align":"none","data-size":"full","src":"http:\/\/i64.photobucket.com\/albums\/h186\/ovreagr\/Car%20Parts\/IMAG2939_zpsmv9tjyla.jpg"}[/IMG2]


The metal "spring" on the door that activates the switch: [IMG2=JSON]{"data-align":"none","data-size":"full","src":"http:\/\/i64.photobucket.com\/albums\/h186\/ovreagr\/Car%20Parts\/IMAG2940_zpskv9xmog5.jpg"}[/IMG2]


This was the original wiring mess that I redid on the original switch: [IMG2=JSON]{"data-align":"none","data-size":"full","src":"http:\/\/i64.photobucket.com\/albums\/h186\/ovreagr\/Car%20Parts\/HTCINC510_zpszx9iqy9n.jpg"}[/IMG2]


Hopefully you can see those images. FF isn't loading photobucket images in the browser for me anymore.
 
Those are simple micro switches. Do you need one like the black with blue connectors in last picture? They look look like similar switches. I would use highest rated that would physically fit your enclosure.
Some handle more current and voltage than others. These are a few bucks a piece unless you want gold contacts then price goes up 15 or 20.
I can mail you some or you can order from mouser, newwark. Used to be a grainger on Mint St in Charlotte.
http://www.nteinc.com/switches/pdf/switch2010.pdf pages 62, 63,64,65
 
Ok, revive and back on topic. ;)

How about just using a magnetic (NC) switch to turn on the lights when the door opens? Wouldn't that be easier? I could just use double sided tape for both contacts and be done!

Something like A) or D) from McMaster.
 
You would need to look at how the switch contacts are setup in rest state or relative to the magnet and how the switch will be mounted. I would think if going with a magnetic switch your going to need NO contacts so that when the switch opens up the contacts would close turning on the light. IF you use NC contacts on that type of switch the light would stay on. A limit switch you would use NC contacts if the plunger is held in by the door till the door opens allowing the contacts to go to the closed position.
 
You would need to look at how the switch contacts are setup in rest state or relative to the magnet and how the switch will be mounted. I would think if going with a magnetic switch your going to need NO contacts so that when the switch opens up the contacts would close turning on the light. IF you use NC contacts on that type of switch the light would stay on. A limit switch you would use NC contacts if the plunger is held in by the door till the door opens allowing the contacts to go to the closed position.
Well crap, that's the opposite of what I read for magnetic switches. EDIT: Perhaps I was confused with magnetic switches for alarm systems vs. just on/off functions.... damn.
 
Yea a alarm would more than likely use NC And be looking to open up a circuit when the window or door opens. Looking at that link you had posted you could get those style switches in either contact arrangement and some have both in same switch.
 
Does it matter if the switching voltage says 24v (switch A. on that link for example) and I have a 12v setup? My understanding was that switching voltage was not the required minimum.
 
Usually they are rated for max voltage not a min rating. 12vdc should be fine for what you are doing since it will be low amp draw for leds.
 
Let's make it really complicated and do a relay. So when you use your key or turn the dial to the last digit, it trips the relay and turns the light on.
 
What about the switching current? The one I referred to earlier has either 1A or 2A switching current. The LEDs have a listed current draw of 4500mA for the full run. Is that going to be a problem or is it more for wire and fuse sizing?
 
Thats 4.5a current draw for full run. Are you planning on using the full run?
 
No way to know for sure without putting a meter on it on but prob close but I wouldn't try to size the switch right on the limit. A limit switch usually has a higher amp rating so more than likely it would be rated for 5 amps or more and cover it. The magnetic style are usually reed type switches and handle lower current ratings around 1-2 amps
 
No way to know for sure without putting a meter on it on but prob close but I wouldn't try to size the switch right on the limit. A limit switch usually has a higher amp rating so more than likely it would be rated for 5 amps or more and cover it. The magnetic style are usually reed type switches and handle lower current ratings around 1-2 amps
Damn, so that idea is DOA then. Where the heck do you find a 5+ amp magnetic switch...
 
Thats where that relay that someone mention earlier comes in. Relay handles current for lights and magnetic switch closes and entergises relay
 
Thats where that relay that someone mention earlier comes in. Relay handles current for lights and magnetic switch closes and entergises relay
OH! I did not know that.... obviously. I thought @Unknownpro was just giving me a hard time! ;) What sort of relay would I need though?
 
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Looking at it on my phone but looks like what you need.
 
Cool, I'll give them a try then. Do you think the magnets will read correctly if they are mounted perpendicular? Or do they have to be "face-to-face" to function properly?
 
Cool, I'll give them a try then. Do you think the magnets will read correctly if they are mounted perpendicular? Or do they have to be "face-to-face" to function properly?


Can't say on those as I have never used them. But some it matters on. I would recommend testing them with a meter reading continuity before you mount them to see what kind of tolerance you can achieve and them still work reliable. The ones I deal with for machine safety to monitor guards are in place usually can only have about 1/4" max between the sensing faces to keep them working reliable. 1/8" usually works better. Normally they are just reed switches inside base ( part with wires) and the magnets in the target piece (part without wires) is what pulls the contacts in the reed switch to change state when it is opened and closed. Some are sensitve to direction of opening and closing is reason I recommend testing it before mounting to make sure it is reliable.
 
first step is safety, make sure you cut the power off

a50.jpg
 
Ok, maybe it is the lack of sleep, but I feel like I am out of my depth here. How the heck would you wire that relay and mag switch?

lol, or maybe just go back to this limit switch if I can figure out how to mount it inside of the safe. Somehow I don't think double sided tape will hold up! :p
This one is just + from outlet to Common and + from lights to NC right? Then just link the - from each?
 
There are lots of options out there. Personally, I'm all for the simple method.

Just go to Home Depot and buy a door switch, like this one:

http://www.homedepot.com/p/Gardner-...sh-Button-Door-Switch-1-Pack-GSW-SK/100180864

Mount it in a small box and mount the box in a convenient location on one of your safe sidewalls, where you can adjust it to suit the door position.

It's plenty rugged enough to last you virtually forever, it's large enough to make adjustments an easy deal, it's cheap...and it's readily available at your local Home Depot.
 
There are lots of options out there. Personally, I'm all for the simple method.

Just go to Home Depot and buy a door switch, like this one:

http://www.homedepot.com/p/Gardner-...sh-Button-Door-Switch-1-Pack-GSW-SK/100180864

Mount it in a small box and mount the box in a convenient location on one of your safe sidewalls, where you can adjust it to suit the door position.

It's plenty rugged enough to last you virtually forever, it's large enough to make adjustments an easy deal, it's cheap...and it's readily available at your local Home Depot.
Those would definitely work too. The problem would still be how to mount it inside the safe though. The only spot close enough to the door to activate the switch is on the steel door frame. Unfortunately I don't have anything to drill and tap holes to screw anything in and anchor it down. And I still doubt double sided tape will hold up long term. ;)

My previous safe had a similar switch inside a housing and the wedged into a space further away from the door. The safe company had then attached a bent piece of metal to the door that would contact the switch.
Switch (with my re-wiring):
IMAG2939_zpsmv9tjyla.jpg

Metal "spring/lever" to activate switch:
IMAG2940_zpskv9xmog5.jpg


This is basically what I'm trying to recreate in the new safe. Unsuccessfully so far. :p

Sorry @Djstorm100 , I despise the motion switches and am trying to replace the one I currently have with a better setup.
 
We use float switches for hvac work for simple stuff like this. It takes so little pressure to activate them the could actually be mounted with double sided tape or velcro. I have used the in the 24v 10amp and can be had I'd 240v 90amp also.
 
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