Using 7c81 with 5v encoder on bob3 config

More
06 Feb 2026 14:15 - 06 Feb 2026 14:17 #342547 by Nathan40
Hi, 

Please can you share a bit file where i can use 5v encoder inputs on my bob P7 for my 7c81 board. I donot want to use 24v but 5v as a quad encoder fast inputs. Rest pins are fine for a normal 5axis bob3 pins.

thanks
Last edit: 06 Feb 2026 14:17 by Nathan40.

Please Log in or Create an account to join the conversation.

More
06 Feb 2026 15:58 #342553 by PCW
You should be able to use single ended encoder pins directly with a 5V encoder.
The 5abobx3d configuration has encoders on all connectors and the 5abobx2
configuration has encoders on both connectors.

For more input protection, I  would add a say 100 ohm series resistor
to the encoder signal lines.
 

Please Log in or Create an account to join the conversation.

More
06 Feb 2026 16:57 #342556 by Nathan40
Replied by Nathan40 on topic Using 7c81 with 5v encoder on bob3 config
Thanks for your reply. But the cheap Chinese boards require 24v power supply to energize its inputs. So inputs are all not responding to 5v input of the encoder. Kindly help as how to wire the 5v inputs with 7c81.

Please Log in or Create an account to join the conversation.

More
06 Feb 2026 17:48 #342557 by PCW
I was suggesting wiring the encoder directly to the 7C81 pins
on a different 7C81 connector than the BOB.

(with series 100 Ohm resistors for protection from negative voltage spikes)

Please Log in or Create an account to join the conversation.

Moderators: PCWjmelson
Time to create page: 0.275 seconds
Powered by Kunena Forum