KROHNE OPTIMASS with MFC 05x EN - Manual (Page 94)

Installation and Operating Instructions OPTIMASS 93
6 Service and Trouble Shooting
6.1 Diagnostic functions
The following diagnostic functions are available in the submenu Fct. 2.9 DIAGNOSE:
Temperature (menu 2.9.1):
• Displays temperature in either °C or °F. The value should be stable.
Strain (menu 2.9.2 Strain measuring tube / 2.9.3 Strain inner cylinder):
• Value of strain in Ohms. The values should be in the range stated in the table in chapter 7.3.
Wildly unstable value even after temperature stabilisation: the strain gauge has possibly become
delaminated due to the meter being operated over maximum temperature for prolonged periods
of time (please contact KROHNE UK service department).
Frequency (menu 2.9.4):
• Variations in the first digit after the decimal point indicate gas or air in the fluid.
• Worn or eroded flow tube: frequency will increase by around 2...4 Hz meter requires re-calibration
• Coatings can also alter the frequency
• Large fluctuations are seen if the meter is in ‘Start Up’
Drive energy (Energy level/menu 2.9.5):
Typical values for the drive energy level with water as process fluid and no included air or gas are:
OPTIMASS 3000:
(7100)
all sizes: 0...4
OPTIMASS 7000 : 06...40
50...80
0...6
4...10
OPTIMASS 8000: all sizes: 0...5
OPTIMASS 9000: all sizes: 0...5
Higher drive energy levels can occur due to gas or air in the fluid or at the measurement of high viscous
fluids or fluids with high densities.
Sensor A and B (menu 2.9.6 , 2.9.7):
The displayed value should be around:
• 80% for OPTIMASS 7000 – sizes 06 … 40, OPTIMASS 8000, OPTIMASS 9000
• 60% for OPTIMASS 7000– sizes 50 and 80
• 55% for OPTIMASS 3000 (7100) all sizes
Or as per Amplitude setting Menu 5.2.4.
Sensor values should be within 2% of each other.
Communication errors (menu 2.9.8):
Display of the number of communication errors.