Analog reading in BL4S200

Hello,

I am using BL4S200 for my voltage monitoring system.I have a AC voltage transducer, It can monitor AC line voltage and output is RMS value (DC linear output from 0 to 10VDC), So input is 0..300VAC, and output is 0..10VDC (RMS value). When I try to connect output of transducer to BL4S200 analog input, and I set single end unipolar 0..10VDC, I calibrate channel, I am able to have reading, but the precision is fluctuate, Even I can't have stable precised reading on integer value. The reading sample rate is 50ms, According to input and output range, the ratio is 30, for example, when analog channel is reading 4.235VDC, the actual voltage will be 4.235x307.05VAC, after 50ms, I read it again, I might have 4.18VDC, so actual voltage will be 125.4VAC, I use scope to measure the analog input, it looks voltage is pretty stable, like 4.23VDC. I don't know why? Does anybody know how to stabilize the reading.

Thank you for any help Start a New Thread

You can probably make it more stable with some filtering but of course that would slow down your response time.

What type of voltage transducer are you using? If you are using something like CR Magnetics CR4511 it is has 0.5% accuracy. The numbers you show have a difference of 0.55% over full scale (0-300) so they might be within specs.

Mircea Start a New Thread