Looking for a slip ring "J" TC Iron & Constantine for getting a TC signal from a TC mounted through a shaft on a mixer. Omega discontinued SR-2. See link below... Thanks for any help sourcing these!
http://www.omega.com/pptst/SR-2.html
Thank you for your responses!
Does the temperature sensed by the transmitter during operation ever get to a level above whatever the 75% of span for that type R T/C is?
In normal operation never get above 72% of span. It worked for 9 months to 20 ma. This loop is a RCRA covered loop and needs...
Have a Rosemount 3144 TT in series with a Rosemount I/P being looped powered from a Fisher Provox AI CL6859 HART smart I/O. When calibrating the loop with a "R" thermocouple simulator and get up over 75% of the range ~ 17ma the reading on Provox goes minus and have to cycle power to the loop to...
MineAutomat,
I would go Fieldbus. I have a DeltaV system with both AS-i for the ROV's and Fieldbus for transmitters. This was installed in the fall of 2001, at that time AS-i was the only thing available for ROV's but now Stonel has a good fieldbus switch. http://www.stonel.com/pdfs/onyxlit04.pdf
Thanks for the responses! It appears the 60 conductor cable got wet and with the cold winter we had here in the northeast,now with a week of warm weather the cable's capacitance has changed hence the induced voltage has went up.
Added snubbers across the 12 discrete inputs to drain the induced...
http://www.easydeltav.com/pd/PDS_ClassicIO.pdf
Check page 19 for the specs.
Here is what appears to be working. Put a snubber of 1uF cap in series with a 100 ohm resistor to put a 2500 ohms AC equivalent load to ground to discharge this induced voltage.
Thanks for the response! The current is 2ma. The wire size is a plant standard size. This problem just appeared on Wednesday or it was noticed on Wednesday. Thanks again....
Have a 60 conductor 14 AWG cable going out 300' in 1.5" plastibond conduit to level switches, open/closed valve position switches and pressure switches out in a tank farm. While performing a monthly interlock check found that the inputs to the DeltaV DI card never changed state from "1" to "0"...
ScottyUK,
This transmitter is used to control vacuum on a kettle. When the batch is complete the kettle gets pressured up 10 15psi which is well above its range of 1000 mmg. So thats why this discussion was started. If there are to many nusance "Bad transmitter errors" no one will...
Thanks for all the replies! This is a pressure transmitter sending a 4-20ma representing 0-1000mmHg. When the system get pressured up to 5 psig the full scale value exceedes the 22ma limit in the DCS system and reports a transmitter error. There is a 250 ohm resistor in parrellel with the 4-20ma...
