Npn sensor usb port conflict?

3hreeKreator 2021-02-15 20:52:41 UTC #1

Hello;

Using a WORKING NPN NO DC 6-36V 300mA LJC18A3-B-Z/BX Sensor. TESTED IT on my original FT-5 and works fantastic,

BUT on my new build(same RAMPS 1.4V KEYES BOARD), the SENSOR will only operate properly while plugged into my computer thru USB.prot (The SENSOR's light stays on, when not connected thru USB, likewise the Z-AXIS motors locked_light being on meaning Z -STOP is triggered and Z-MOTORS won't budge.

PLUG it in thru USB and the issue disappears, light goes ON/OFF as it should. And Z-MOTORS work properly - PLEASE tell me what could be wrong?

(SENSOR behaves the same way in every STOP PORT, regular mechanical sensors behave normally - VERY BIZARRE!

csorrows 2021-02-16 01:19:24 UTC #2

Are you sure 5v is working on the ramps board? This is typically pretty easy to blow by shorting an endstop header. Plugging in the USB provides the missing 5v.

I moved this out of the FT-5 category as you have changed the controller.

3hreeKreator 2021-02-16 10:24:01 UTC #3

WOW! you described the dilemma with cutting discernment

Yes, I would say it is very possible I "shorted" the END STOP header(during wiring I kept getting shocked and pretty sure the SENSE/POSITIVE contacted the NEGATIVE wire, didn't realize this could cause permanent damage to the board?),

BUT would this cause all the END STOP headers to become shorted? Because it fails in every Header - Only MECHANICAL END STOPS work without the USB plugged in.

I should also add it did work briefly prior to my getting shocked again and again

csorrows 2021-02-16 21:25:52 UTC #5

It does not cause a header to be shorted. It damages the 5v regulator on the Mega board. This is very common as the RAMPS board has no protection for it.

I found a thread on the Thingiverse forum that covers it pretty well HERE.

I would personally stay away from the RAMPS and move toward some kind of MKS controller.

3hreeKreator 2021-02-16 23:52:16 UTC #6

Your replies are a Godsend, I truly appreciate all the insight Coscrows (I Was truly stumped, I feel like I've just taken a short Education on SENSOR/SHORTS and END STOP Headers!)

csorrows 2021-02-17 00:49:05 UTC #7

You are very welcome. That is what this forum was created for.

I'm actually surprised our forum leadership didn't chip in as well. But that's fine.

Please let us know how it works out and what your solution was. This forum gets a ton of viewer traffic by people who never post. It seems dead but is actually quite a well used resource.

Take care.