Not sure how to describe this project which may be why I have not had any success searching for examples of it! Any pointers in the right direction are most welcome!
I have several voltage feeds going to assorted loads on my CNC, 68v, 24v,12v, 5v (all DC) what I'd like to do is have a control LCD that told me which ones were active and which were not... I don't need to monitor the exact voltage for each feed, just if it's live or not will do. (There are 5 x 68v, 4x 24v, 5x 12v and 5 x 5v to be watched)
I did stumble upon the voltage divider circuit, although this seems like overkill - I don't need a measurement of the voltage, just if it's there!
I'd use relays. If the line is active, relay is pulled and it feeds your digital input with 5V. Probably safest option.
I know there is 5V, 12V, 24V relays, but i'm not sure about 68V relays.
The zener is probably an easy one, needing two components, idk if its any cheaper than two resistors tho,
Other than that perhaps an optoisolater? Still need a resistor tho
MANY THANKS for the fast responses guys!
Yea, agree that the relays would be the safest option, I did look for relays, but it got expensive real fast!
The Zener solution sounds simple and elegant... and I only need to run wire per feed, exactly what I was looking for.
Rob (anyone) may I impose upon your hospitality and ask if you would be kind enough to suggest a suitable zener for this? I've just had a look on line and the choices are bewildering!
The opto route sounds worth exploring too... (next job!)
