Replaced a Jordan MV-1020 with an RCV SEVA-200. Feedback 4-20 gives constant 100% open indication at HMI regardless of valve position. Two identical valves were replaced and both act the same way (yes, I broke both of them). My predecessor had replaced other valves with an older model (non-SEVA)of RCV valve with success.
I have connected my Fluke process meter to both the valve output signal and have simulated a feedback signal to the PLC with valid indications for both tests. The selector switch is at position 3 for 4-20 signals. I have verified polarity and in a fit of frustration have tried reversing the signal wires (my plant has unique properties. Depending on which contractor did an installation black may be - or +).
Any pointers for where to look next?
I have connected my Fluke process meter to both the valve output signal and have simulated a feedback signal to the PLC with valid indications for both tests. The selector switch is at position 3 for 4-20 signals. I have verified polarity and in a fit of frustration have tried reversing the signal wires (my plant has unique properties. Depending on which contractor did an installation black may be - or +).
Any pointers for where to look next?