GeneL

Hi Joe to update this is exactly what I've done I have used this equipment previously with a 20 cell stack fuel cell. Now I'm trying to interface the switcher with a Unitronics USP-104-B10 I would like to sent it SCPI commands from the PLC's USB port via a USB/GPIB 82357B interface. I'm not the PLC programmer, I just want to see if my request is feasible. I just want to include the 34970 at the test stand. I don't even know if it is possible to integrate the Two systems or even if it is necessary at this point. What I used before was Visual Studio (Visual Basic) and it worked quite well. I am guessing that I can just program the switcher to scan through a list of channels and arm an alarm output based on the voltages measured. Gene

Thanks Joe, I certainly understand the limits on the AI unit but I was hoping for an easy fix. Our measurements can be critical in the 10s of millivolts so working with "real voltage measuring devices is likely the path to success. The TT238 is a nice unit, but it would be a bit too expensive for 30 channels perhaps in conjunction with a multiplexer or a physical switching device??? BTW I agree the divider network is better described as less sensitive - reducing resolution as opposed to "amplifying error" Thanks for your response I will keep the forum posted. GeneL

I wish to measure analog voltages greater than 10 vdc. Am I allowed to reference a UIA-08 input module to 10 vdc and measure up to 20 vdc? If not why not or better yet, how can I measure values greater than 10 volts? I have used voltage dividers but they tend to amplify error. I am looking for a "differential amplifier" approach. Admittedly, I'm new to Unitronics hardware, but I haven't seen a differential input device. Gene