Hello.
I have problem with Wind output on driver.
Machine is from 2020, assist works normally but starts have problem to turn on.
So I change 24V valve and now it stop working.
There was voltage on Wind output and light up connected 24V LED.
But after connecting valve the voltage drop to 0.
The LED lighting up when project was made on laser… but now its constantly on.
Could something broke on drivers PCB?
Unfortunately, yes.
The Ruida controller output is active-low, so the air valve connects between +24 V and the output pin. However, the valve may conduct more current than the transistor in the controller can handle and, as a result, the transistor will fail.
That means the transistor has failed and conducts current all the time, rather than acting as a switch.
While it is possible to replace that transistor, it requires the correct tools and soldering equipment; if you’ve never done such work before, this task will be both difficult and expensive.
The least-awful choice may be to replace the entire controller to get the machine running again, after which you can explore replacing the failed transistor.
The best way to prevent this failure is to put a DC-DC solid-state relay between the controller pin and the valve, so the controller sees a very small current and the relay handles the valve’s high current.
Previous discussions cover many details:
If you are measuring from ground to wind, then when it’s active it should read 0 volts.
Do you have snub diodes across the coils?
If not the voltages can get to hundreds of volts and kill off the switching transistor.
Most of these don’t fail in an ON state, they usually burn open, so to speak. If so your led and air should be on all the time?
