Limit switch wiring question.. November 16, 2017 04:26PM |
Registered: 7 years ago Posts: 128 |
Endstop switch pulls signal from GND to +3.3v when triggered - Active High/NC Endstop switch pulls signal from +3.3v to GND when triggered - Active Low/NO
Re: Limit switch wiring question.. November 16, 2017 06:13PM |
Registered: 10 years ago Posts: 14,672 |
Re: Limit switch wiring question.. November 16, 2017 07:18PM |
Registered: 8 years ago Posts: 3,525 |
Endstop switch pulls signal from GND to +3.3v when triggered - Active High/NC Endstop switch pulls signal from +3.3v to GND when triggered - Active Low/NO
Re: Limit switch wiring question.. November 16, 2017 08:17PM |
Registered: 6 years ago Posts: 1,863 |
Re: Limit switch wiring question.. November 16, 2017 08:44PM |
Registered: 7 years ago Posts: 128 |
Re: Limit switch wiring question.. November 17, 2017 02:05AM |
Registered: 8 years ago Posts: 3,525 |
Re: Limit switch wiring question.. November 17, 2017 03:23AM |
Registered: 10 years ago Posts: 14,672 |
Quote
DjDemonD
I am almost certainly wrong but... in the description there:
Endstop switch pulls signal from GND to +3.3v when triggered - Active High/NC Endstop switch pulls signal from +3.3v to GND when triggered - Active Low/NO
Aren't the designations NC and NO here the wrong way around. A Normally Open switch reads 0v open and 3.3v closed and is active high. A normally closed switch reads 3.3v open and 0v closed and therefore is active low. NC fails-safe as a wire break causes the controller to read 0v, and stop rather than crash the axis.