8/16/2011 5:03 PM | |
Joined: 9/23/2005 Last visit: 8/27/2024 Posts: 4347 Rating:
|
Hi, Can you express this conversion in a formula? |
Denilson Pegaia |
|
8/16/2011 6:56 PM | |
Joined: 9/23/2005 Last visit: 8/27/2024 Posts: 4347 Rating:
|
Hi, in this case I suggest you use a ready made block for 4..20mA Sample program: SCALE and UNSCALE /tf/WW/en/Posts/31698#top Adjust 4mA (0mV) = 0.01 20mA (50mV) = 100.0 |
Denilson Pegaia |
|
8/16/2011 8:31 PM | |
Joined: 7/7/2010 Last visit: 8/30/2024 Posts: 15125 Rating:
|
If the PLC input is linear, you should do as Pegaia suggests. If it is not, find the formula for the relationship between the input and the mR/hr. It will be similar to the one I posed above. If you have something measuring counts per unit time (cps), the big question is whether your log is already handled by the instrument or whether the plc has to do the math to obtain the value. Alternatively, you can generate a lot of sample values in a table, and simple do a table lookup in the PLC code to get the value. Easier than RTD bridgelook up tables! |
science guy |
|
Follow us on