Appendix A: Technical reference
A.3 Maximum Process Temperature Chart
SITRANS LR250 with FOUNDATION FIELDBUS
Operating Instructions, 09/2021, A5E32221411-AH
241
If two faults are present at the same time, the fault code, error text, and error icon for each
fault are displayed alternately. For example, Loss of Echo and faulty power supply:
Upon receiving a reliable echo, the loss of echo condition is aborted, the Service Required
icon and error message are cleared, and the reading returns to the current level.
A.2.10.1
LOE Timer
Loss of Echo (LOE) Timer (2.3.6.)
determines the length of time a Loss of Echo (LOE)
condition will persist before the function block will show a status of BAD or UNCERTAIN. The
default is 100 seconds.
A.3
Maximum Process Temperature Chart
WARNING
Exceeded maximum internal and process temperatures
Danger of device malfunction
•
Internal temperature must not 80 ° C (+176 °F).
•
Process temperature must not exceed limits specified by the antenna type.
Note
•
The chart below is for guidance only.
•
The chart does not represent every possible process connection arrangement. For
example, it will NOT apply if you are mounting SITRANS LR250 directly on a metallic vessel
surface.
•
The chart does not take into consideration heating from direct sunlight exposure.