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Third party software and hardware support forums. => PoKeys => Topic started by: Lotus23 on April 28, 2021, 07:29:57 PM

Title: NPN proximity sensors 24v supply & pokeys 57
Post by: Lotus23 on April 28, 2021, 07:29:57 PM

Hi
My plan was to use those chinese NPN proximity sensors for homing.
However I now realise their output is beyond the 5V max on the pokeys board.
I'm using a 24V power supply.
Is there a solution to this, possibly a voltage divider using a couple of resistors?

Thanks Patrick

Title: Re: NPN proximity sensors 24v supply & pokeys 57
Post by: MarSLO on March 01, 2022, 07:10:19 AM

Hi
The Polabs have a homing sensor.
For idea or wiring, you can check.
https://blog.poscope.com/homing-sensor-pohome1irnpn/
and product
https://www.poscope.com/product/homing-sensor-pohome1irnpn/

Title: Re: NPN proximity sensors 24v supply & pokeys 57
Post by: MN300 on March 02, 2022, 07:44:11 AM

Hi Patrick,

Please post the model number of your sensors.
Some have pull up resistors that would raise the output signal voltage too high for a 5V input. Others have an open collector output that acts like a switch to ground and would work with Pokey directly.
Knowing which you have will make it possible to answer your question.

John

Title: Re: NPN proximity sensors 24v supply & pokeys 57
Post by: Philmill on March 12, 2022, 04:01:54 PM

Hi,

Try this one from Ali they have a range from 5V-24V
search for EE SX 671
If you like quality buy same from Omron.

Ph!l

Title: Re: NPN proximity sensors 24v supply & pokeys 57
Post by: MN300 on March 12, 2022, 04:24:32 PM

The EE SX671 may not be suitable for your CNC use.

ee-sx47_67_ds_e_13_2_csm483.pdf
The datasheet , page 5 says;

"These Photomicrosensors have an IP50 (conforms to IEC) enclosure
and do not have a water-proof or dust-proof structure. Therefore, do
not use them in applications in which the sensor will be subjected to
splashes from water, oil, or any other liquid. Liquid entering the
Sensor may result in malfunction."

Title: Re: NPN proximity sensors 24v supply & pokeys 57
Post by: lecso77 on June 14, 2022, 05:34:25 AM

Why don't you use an optocoupler for this purpose? There is also a wiring diagram in the PoKeys manual.
You will need (per sensor) 1 optocoupler, 1 2k2 resistor, 1 390R resistor, 1 5k1 resistor. You solder it to a test panel and you're done.
Or: you buy the factory PoOptoIn panel from the manufacturer's site. (See: https://www.poscope.com/product/pooptoin/ (https://www.poscope.com/product/pooptoin/) )

Title: Re: NPN proximity sensors 24v supply & pokeys 57
Post by: johnny4827 on May 01, 2023, 01:31:30 PM

It seems like a good plan. But you can try the EE SX 671.