M
New and old pressure transmitter 4-20 ma output is negative. Company wanted to upgrade to a yokagowa transmitter. Upon confirming proper operation I realized the output was negative. I slammed the old Honeywell (was working fine before upgrade) back together and the output is negative. I'm very puzzed. Thing is, the transmitters 4-20 is sent to a distributed computer system that seems to expect a negative signal. I think it "expects" because it displays a positive pressure, and thus everything seems to be functioning properly. Still, I'm very curious. Why is this negative? I think it's worth while to add that I couldn't find a setting on the Hart controller to switch sign. Oh, and also, the transmitter is a single impulse line with the other side capped, so I "think" that means it's absolute pressure?
Thanks in advance
Micheal
Thanks in advance
Micheal