grounded731
Member
So this is what can happen if you mix an electrician + Fluke 87 + Flex IO system...
Because the -it8 thermocouple modules tend to go out of calibration often and then require an outside contractor to fix/calibrate, I tested to see if there were any possibility of stray voltages and/or spikes causing this to be more a problem than necessary....and found that every 2.5 seconds up to 4.32vdc shows at the tc inputs(1ms max record)...again, measured from ground to the tc+ terminal and got max 19.76vdc...etc.
There is an max vac component of 6.48 measured at ground to tc-.
The A-B manual shows these to be wired correctly, matched to appropriate base, separate vdc supply from the discrete and other analog modules.
Am I seeing something common to PLC's that poll for a measurement?... do I have a noise issue?...or do I just have too much time available to test for this stuff?!
Brian J. Pryor
Because the -it8 thermocouple modules tend to go out of calibration often and then require an outside contractor to fix/calibrate, I tested to see if there were any possibility of stray voltages and/or spikes causing this to be more a problem than necessary....and found that every 2.5 seconds up to 4.32vdc shows at the tc inputs(1ms max record)...again, measured from ground to the tc+ terminal and got max 19.76vdc...etc.
There is an max vac component of 6.48 measured at ground to tc-.
The A-B manual shows these to be wired correctly, matched to appropriate base, separate vdc supply from the discrete and other analog modules.
Am I seeing something common to PLC's that poll for a measurement?... do I have a noise issue?...or do I just have too much time available to test for this stuff?!
Brian J. Pryor
