AO Extension - right values
Hi, can anyone give me a hint how to control the AO Add-on? I mean, what uint value means +10V at the OUT, what uint value gives 0V at the OUT? right now it feels like jeopardy ^^ ..e.g. if I set the channel to uint=10000, I get 4.4V at the OUT. channel transformation is identity, power supply with 5V and 24V for AO
thanks in advance
Which addon is it specifically? Is it the I2C addon from this topic?
Apologies for the late reply. I think the input should be 12V instead of 24 though, but if you could take a photo of the device it would be very helpful.
Yes, it’s the old AO add on shown in the picture.
I found out that I can adjust the output voltage from 0-10V with an uint from 0....4095. If I put it 4096 it jumps back to 0V.
Can you confirm ?
Also is it allowed to apply 24V as supply or will it damage the unit?
Right now I am facing the problem of noise injection into the cable at the analog out. Even though I use a PIMPF Cat7 cable (approx 2m long) at the AO, parallel running cables inject a voltage around 0.5...0.6V. I have a LED power supply connected which can be dimmed and which switches on/off at 0.6V and now the LEDs are blinking^^.
Any idea how to improve ? (I know.. I shouldn’t lay the cat7 along with power cables, but I didn’t expect so huge effects. However, I will try to find an alternative route :) )
Found out that EMC was not an issue, but the LED power supply. I added a 10k resistor in parallel to the 0-10V input which fixed the 0V problem.
Only poor thing now is the bad behaviour of Mervis with the AO extension board. I added a ramp for smooth dimm up and down, but it's actually not smooth but rather stepwise:
Any idea how to fix? Maybe the problem comes from the transformation "to_uint(real)" ?