Help Wiring up a High Precision switch

Thread Starter

TTalma

Joined Feb 8, 2019
2
I have a CNC machine. I purchased a High precision switch off of eBay (Triggers at the same spot within 3 microns), to set my Z depth.

The switch is an Omron D5A-8511 (Data sheet here: https://www.ia.omron.com/data_pdf/cat/d5a_ds_e_2_2_csm591.pdf)

Anyway I assumed like most switches once the plunger is depressed it would make a connection. But it does not work that way! When connecting my multi-meter it does not show continuity when depressed.

I wired it to +5V with a 1k resistor as the load as shown in the data sheet, And the little red LED in the switch lit up when the plunger was pressed. How do I connect this switch so that it can either trigger an input (Either +5V, or 0V I have both available on my input board)?

Thanks
 

wayneh

Joined Sep 9, 2010
17,498
When the LED is lit, I think you’d find 5V on one side of the load and nearly 0V on the other. When not pressed, there will be 5V on both sides, assuming it’s on the high side.
 

Tonyr1084

Joined Sep 24, 2015
7,899
If your switch has brown and blue wires (or black and white) they are just like any other switch. Do you need assistance understanding how switches are wired into circuits? If so - that's an easy answer.

Z Switch.jpg
 

MaxHeadRoom

Joined Jul 18, 2013
28,686
You need to post the nature of your input, you need a sourcing input as the SS version is sink through a NPN output.
Not sure why you did not see it switch when providing a pull-up resistor? Input board Number.?
Max.
 

shortbus

Joined Sep 30, 2009
10,045
It is a NC switch. It opens when making contact. Did you follow the guide lines on page #6 in the pdf? The one called "Connection to Power Source" ?

This is for a height setter correct? Not a real limit switch.
 

Thread Starter

TTalma

Joined Feb 8, 2019
2
Thanks for the help. The switch is not a straight pass through as TonyR1084's drawing shows. It is some sort of logic switch. Apparently I was not sinking enough current through the switch to make my input board happy.

I wired it so that the brown wire (+ input) was connected to +5V, added a 120 Ohm resistor as the load on the blue wire and connected that to a low trigger input on my board. And now when depressing the plunger it triggers the input. I tried removing the resistor to make sure that it was not a bad connection and the input does not trigger when the plunger is depressed, so the resistor is needed as the load.

Thanks again for the help.
 

MaxHeadRoom

Joined Jul 18, 2013
28,686
It is a NC switch. It opens when making contact. Did you follow the guide lines on page #6 in the pdf? The one called "Connection to Power Source" ?

This is for a height setter correct? Not a real limit switch.
The output for the 8511 is N.O. open collector PNP transistor.
It is two wire so the load can go in either the pos or neg side.
The resistor is needed for a two wire to function.
Max.
 
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