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I need to work on a panel for an industrial product. The idea is that the signals from these buttons go to a PCB with an MCU which then communicates with a central MCU about the state of these buttons.

Previously i have worked with buttons which are PCB mount (soldered). However, most of these panel mount ones come with contact blocks. This is an example of what i am looking at:

https://uk.rs-online.com/web/p/push-button-complete-units/3729108/

My question, is what would be the best way to interface these to a PCB? A connector on the PCB side and then just wire into these?

There are a few of these buttons so I could have one big connector which screws into all but i can just see so many issues in the assembly stage.

I can't find PCB mount ones (most of them are out of stock and it needs to connected to a panel)..

Question is: Is there a better way to mount these to a PCB? Something that removes the need of several harnesses? I have read 'plug in connector' in the datasheet of a few of these but there is no mention of what those connectors are.

Hasman404
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This type of pushbutton is designed to be used in circuits with higher voltages and currents than you'll use on your MCU, for example with motor contactors and machine tool relays. This is why they have screw terminals designed for heavier gauge wire than you need with your MCU.

If you must interconnect these to a PCB, your best bet is to have a set of PCB-mounted screw terminals like this on your MCU board:

PCB Screw terminal from TE

…and a wiring harness between this and the button.

If this is truly an industrial product, there are probably some standards you should be following in the assembly of the panel. (In the US, we would follow UL508, but judging from your product link, a corresponding IEC standards may apply.) This is especially important if the enclosure will contain power circuits, or other control circuits operating at higher voltages than your MCU.

Theodore
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You wire them to an PLC IO module.

Or, you get the addressable variant, like Eaton SmartWire, and talk to those. You can even get wireless ones today!

What you should not do is wire the low voltage mcu signals directly to these buttons over cables. The cables and buttons are too susceptible to noise to be reliable that way. They also bounce a lot.

(Eaton's M22-K10 are compatible with 5V and 1mA of wetting current, they specify 1 missed make for 5 x 10^-6 operations)

If you want to make your own input for this, lookup IEC 61131-2.
ST recently launched a new chip to make this super easy, for example the CLT03-2Q3. But TI has the SN65HVS880 for 8 of those compliant inputs.

Jeroen3
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