Using a Foxboro model 13A pneumatic differential pressure transmitter to measure water level inside a plastic tube, and report that level as a 3-15 PSI air pressure signal to a remote "receiver" gauge.
This lab demonstrates the basic operation of any pneumatic signaling system: where a variable air pressure represents some other variable (in this case, water level). Once upon a time, most industrial instruments worked like this: using 3-15 PSI pneumatic signals to represent pressures, levels, temperatures, flows, and even some analytical variables!
