While searching the forum today, I realized I never posted an answer to Danw2's excellent response in my thread on flame rods:
thread698-285700
The cabling changes constituted a change from original wiring and did work for a while, but problems recurred after awhile with the furnace in service...
The furnace in our delayed coking unit tripped on a low flow ESD last night; we have had issues with this in the past following a cold night coupled with precipitation. The DP orifice flow transmitters are installed on each of the 4" charge lines to the furnace with an ESD setpoint of 2.61...
We have had issues with intermittent signal from 9 of 28 flame rods installed in our coker furnace. Through discussions with FireEye, the suggested solution was to remove extraneous cabling and rerouting to avoid any crosstalk on the Belden coaxial cable. Wiring modifications have been...