Endress+Hauser Micropilot FMR56 - Page 146

The "Expert" menu Micropilot FMR50/FMR51/FMR52/FMR53/FMR54/FMR56/FMR57 FOUNDATION Fieldbus
146 Endress+Hauser
Step 3: Configuration of the foam detection.
Configure Advanced Diagnostics 2 as follows:
• Assign diagnostic signal 2 = Relative echo amplitude
• Calculation type 2 = Mean
• Sample time 2 = 60 s
• Check mode 2 = Lower limit
• Lower limit 2 = 10 dB
With this setting Advanced Diagnostics 2 (internally) assumes the following value:
• 0 (INACTIVE) - if the amplitude exceeds 10 dB (i.e.: there is no foam)
• 1 (ACTIVE) - if the amplitude is below 10 dB (i.e.: foam detected).
Step 4: Configuration of the logic block linking
Configure Advanced Diagnostics 2 as follows:
• Link AD 2 to = Digital output AD 1
• Linking logic AD 2 = AND
With this setting, the output of Advanced Diagnostics 2 assumes the following value:
• 0 (INACTIVE) - if at least one of the two blocks is in the "0" (INACTIVE) status.
• 1 (ACTIVE) - if both blocks are in the "1" (ACTIVE) status.
For the example this means:
– A diagnostic signal is output, if the level is within the defined range and the signal
amplitude is below 10 dB. This signal can be linked to the status output of the device
(→  116).
– If, on the other hand, the level is out of the defined range or if the signal amplitude
exceeds 10 dB, no diagnostic signal is transmitted via the switch output.
The status can also be linked to the DI block and transmitted to the fieldbus.