I’m new to this forum and my experience with the K8055 and K8061 interfaces pretty much sum up to switches and relays.
Now I’m trying to log specifically AC voltage.
What I need to do can be described as basically plugging the wires into the electrical outlet at home and measuring variances in the voltage. Well, having a multimeter logging the data into the PC.
By the way, please bear in mind that I’m quite a newbie in what concerns to electronics, so there are most probably some electronic parts that I don’t know of and could easily answer some of my questions.
So, first of all, we would need to convert alternate current (240V @ 50Hz) into low-voltage direct current (0-10VDC for the analog input).
This means we have two challenges here (I guess):
Expected AC voltage would vary between 0 and 270V (being 270V AC converted into for example 9,9V; anything over that could just be considered out-of-range). Also the DC converted voltage must be limited to 10V for interface health reasons
Timing is critical - besides the fast conversion, it must preserve the sudden voltage variances, since they might occur in 1/20th of a second (or maybe I’m being paranoid, but at most 50ms samples would be what I’m counting on).
Now, is this possible and do you have an idea of how it can be achieved?
Thank you in advance for your time. I’ll be looking forward to some feedback
Velleman can’t support any project only our products “stand-alone”.
I think the sampling speed of the card is also to slow to sample 50 Hz your converted voltage (0…10V).
AC voltage can not be used on any input.
Can you be more specific on your first sentence? (Velleman can support any project only our products “stand-alone”)
Which stand-alone products would you be referring to?
I am aware that I can’t use AC voltage directly in the inputs. Thus my wish to convert to DC.
About the 50Hz… wouldn’t you agree that 50 samples per second is more than what’s actually needed?
I was counting on somewhat around 20 samples per second, which is perfectly possible with the K8061.
So the challenge here is to convert AC to DC, but preserve the voltage variations (make the DC voltage somewhat proportional to the AC voltage).
And that’s what I don’t exactly know how.
Any suggestions?
EDIT: I’m meeting a friend later today whose latest major project is pretty much related to this matter.
If that leads somewhere, I’ll post more info on this subject.
The meeting with my friend gave some results
I’ll post the final project when it’s done and working.
We’re like half the way there… just some minor adjustments remaining and final testing.
It starts with a rectifying bridge right on the 240V AC source, thus avoiding the stabilization innerent to adaptors.
[size=150]That’s around 320V DC. Not for the faint-hearted.[/size]
So we’re not quite in a position to rush things here.
But I promise I’ll post it, so we can keep some proof-of-concept of human insanity.
