That would probably be because you connected the zener diode across the coil (like you connected the 4004 diode?)?...
Finally I use common 4004 diodes, I tested a lot of zenner diodes and they are pretty much the same (5 ms open/close time), as 4004 are cheaper, I used these.
...
In your very first post of this thread, you said:Hey folks!
I have been working in the prototype of the "Water Printer". The electronics works like a charm with 0.1 ms precision. Valves open/close time is 6ms, fast enough for me.
Finally I use common 4004 diodes, I tested a lot of zenner diodes and they are pretty much the same (5 ms open/close time), as 4004 are cheaper, I used these.
You are right! I connected the zenner diode incorrectly. In some days I will try and test the alternative you showed me. Thanks!That would probably be because you connected the zener diode across the coil (like you connected the 4004 diode?)?
To use zener diodes as snubbers you need one zener diode (reversed) in series with the 4004 diode.
So the diodes are in series like this;
--->|----|<---
then the diode pair goes across the coil, with the 4004 in the same orientation as you would normally use.
Good point. By that time I was making the first tests and using some big and heavier valves. The comparison between “4004 diode” vs “none” with the newer valves made little difference so I went with the most conservative (and cheaper) alternative: 4004 diode.In your very first post of this thread, you said:
"Actually I´m using one 1N4004 diode parallel-connected to each solenoid. This protection works fine but it has a big controversial issue: the close time is widely increased (by 2x or 3x) and makes my system not to work correctly."
How is it that the "...increased (by 2x or 3x)..." close time is no longer a problem?