proximity switches

[JAZZCNC]

Which ones do you use if you don't mind me asking Dean?

These https://www.jazzcnc.co.uk/product-pa...y-limit-switch

[reefy86]

These https://www.jazzcnc.co.uk/product-pa...y-limit-switch

Thank you

[cropwell]

As a matter of curiosity, I had to test out an assumption, that these LJ12A3-4-ZBX (NPN NO 4mm) proximity switches are pretty much bullet proof (unless you run end-on into them).

I connected 3 of them up to a 15v power supply and used an LED and a 4k7 resistor as an indicator. If you common the outputs and trigger one sensor all 3 indicator LEDs on the sensors light and the output goes to GND to indicate a Home run. No smoke, no drama.

Connecting the output to GND lights the indicator goes on, even though the sensor is not triggered, but the unit is not damaged.

Connecting the output to +15v and triggering the sensor - OUCH, I thought I had caused it to fail, but a few minutes later it was back in service.

So maybe these units are idiot proof by design, but it seems difficult to turn them into smoke generators.

Cheers,

Rob

[Neale]

There are cheaper options available than those shown by Jazzcnc. I bought a box of ten for about £12 when I built my router some 5 years ago.

One was clearly the wrong type - the fact that it had only two wires, not three, was a clue. One was faulty from day 1 - as I discovered after wiring it in. Since then, two have failed in service. I think that means that I have now finished the box, so if any more fail, I'll be looking to buy from a reliable source!

[cropwell]

I did the same, but all of mine were good (so far) (LJ12A3-4-ZBX (NPN NO 4mm) proximity switches. After jogging end on into a switch, I bought a replacement from a certain Company in Devon for £17.95 (It still stings!!). I changed the approach to sideways on. I suppose it depends on who makes them as to how reliable they are.

Dean would be obliged to replace any faulty switch he supplied, so his mark up is to cover that. Also he has his reputation to think of, so he will have found a reliable supplier of quality switches () and I would expect the switches are tested before dispatch...

[reefy86]

Exactly why I would buy from him even if it did cost more if he sells it I know its good to use. Literally got a huge list ready to send him from his store lol.

[JAZZCNC]

Dean would be obliged to replace any faulty switch he supplied, so his mark up is to cover that. Also he has his reputation to think of, so he will have found a reliable supplier of quality switches () and I would expect the switches are tested before dispatch...

Exactly, Yes you can always buy cheaper if you want to go direct to China and wait. That's all we do, as does just about every other UK supplier, but we have overheads to pay for like any business does so we need a certain amount of profit to survive, that's just business.!
Everything we sell on the website we fit on the machines we build and sell so obviously they have all been well truly tested and it obviously goes without question that if for any reason we had a faulty, anything, it would be replaced ASAP and FOC.

To be honest, that's how the website came about, we had the parts on the shelf that we fit on the machines we build so thought why not offer them for sale. This is why there isn't a massive choice or selection of components. For instance, you've probably noticed we don't offer ball screws or Profiled linear rails even though we have those on the shelf, this is because they are sized and machined to the machines we build and don't want to get into Custom lengths and machining, etc.
As time goes on this might change and if the site builds up then the selection may increase as people enquire about different components and demand warrants the investment.!