Limit Switch Hookup, Hamlin 5802

[juzwuz]

Some sort of limit switches were mounted on my surplus store router but I've never used them. They have the markings: Hamlin 5802. I tried a quick google but I didn't find any wiring instructions. I was just wondering if anybody could point me in the right direction to get these switches working? Thanks!

Justin

[Al_The_Man]

Are these two wire? As Hamlin generally make a reed switch that is actuated by magnet, if so the polarity does not matter.
I may have some Hamlin info somewhere.
Put an ohm meter across the two leads and place a magnet near them to verify this type.
Even the proximity type are megnetic
http://www.hamlin.com/specsheets/59075.pdf
Al.

[juzwuz]

Here's a picture of the switch. I'll try a magnet and meter and see what I get.

[vger]

Looks like these may be one of Hamlin's older hall effect sensors. Here is a link to the data sheet for the ones they make now
http://www.hamlin.com/specsheets/55140%20Issue3.pdf
The ones they have now have a red, black, and blue wire.
Red = Positive supply voltage
Black = Ground (common)
Blue = Output (Open when not actuated, ground when actuated)
Just a guess that the one you have is similar with the white wire being the Ground (common).
Digi-Key is one of their distributors and they list the 55140-3H-02-A-ND at $7.02

Hall effect sensors are pretty cool, no moving parts, sense a small magnetic field, no contact bounce, and they are fast (10 Khz). Some older computer keyboards were made with them in the keys.

You might just try connecting one of them and testing it. Don't forget the pull-up resistor on the output.
Best of luck

Steve

[Al_The_Man]

Originally Posted by juzwuz Here's a picture of the switch. I'll try a magnet and meter and see what I get.

The one you show looks exactly like the ones I have used, if so they are SPDT contact closure, actuated by a magnet, also they are not hall effect.
Also if they are this type, one pair will show zero resistance.
Another clue is if they only used 2 of the 3 connections.
Al.

[juzwuz]

There are 3 of these switches for each axis. It looks like the switches mounted at the travel limits only have 2 of the wires connected. The other remaining switch seems to have all 3 wires connected. It's hard to tell for sure since it's all bundled together into one cable.

I guess I'll separate one switch from the rest of the wires so that I can test it. What should I be looking for though? Should I hook up a ohm meter and check resistance when I put a magnet close by? I'm kinda clueless in terms of these switches. They look pretty simple though, so hopefully I'll be able to get it working. I really appreciate the help...thanks!

Justin

[Al_The_Man]

The ones I used have a magnet supplied by Hamlin about the same size as the part with the # on it.
As I mentioned in the previous post, if they are SPDT they will have a common and a N.O. and a N.C. contact, so there would be zero resistance between two and the third would be infinity (high res).
Placing any magnet near them would operate them, so the pair that showed zero should now show open circuit.
The magnetic type do not need power to check the operation with a meter.
Al.