Operation Manual

6-4
IM 1F5B2-01E
6.5 Action Against Power Failure
• In the case of a power failure, the totalized data value is protected by the EEPROM.
ULTRA YEWFLO cannot operate during a power failure, however, resulting in an
interruption in totalization. It resumes totalization upon recovery from the power
failure (restarts totalization, beginning with the value given immediately before the
power failure) and automatically restores normal operation.
•No backup batteries are necessary for the EEPROM.
6.6 Precautions During Startup
• Because of effects due to external noise, ULTRA YEWFLO may not indicate 0%
when the flowrate is zero, giving an output greater than 0%. If this occurs, first make
sure ULTRA YEWFLO is filled with the process fluid. Then, make a TLA adjust-
ment according to the instructions in Subsection 8.2.3.
If the pipeline is empty during startup, ULTRA YEWFLO may continue to give a 0%
output or remain unstable until it fills with the process fluid.
IMPORTANT
•Whenever possible, pipe ULTRA YEWFLO while exercising care to prevent bubbles
of gas from mixing with the process fluid. (See Section 4.1, “Piping Precautions.”)