Emerson 9739 Manuel D’Utilisation
Procedure
Set AO Cutoff as desired.
The default values for AO Cutoff are as follows:
•
Primary mA output: 0.0 g/sec
•
Secondary mA output: Not-A-Number
Tip
For most applications, the default value of AO Cutoff should be used. Contact Micro Motion customer
service before changing AO Cutoff.
service before changing AO Cutoff.
Interaction between AO Cutoff and process variable cutoffs
When mA Output Process Variable is set to a flow variable (for example, mass flow rate or
volume flow rate), AO Cutoff interacts with Mass Flow Cutoff or Volume Flow Cutoff. The
transmitter puts the cutoff into effect at the highest flow rate at which a cutoff is
applicable.
volume flow rate), AO Cutoff interacts with Mass Flow Cutoff or Volume Flow Cutoff. The
transmitter puts the cutoff into effect at the highest flow rate at which a cutoff is
applicable.
Example: Cutoff interaction
Configuration:
•
mA Output Process Variable
= Mass Flow Rate
•
Frequency Output Process Variable
= Mass Flow Rate
•
AO Cutoff
= 10 g/sec
•
Mass Flow Cutoff
= 15 g/sec
Result: If the mass flow rate drops below 15 g/sec, all outputs representing mass flow will
report zero flow.
report zero flow.
Example: Cutoff interaction
Configuration:
•
mA Output Process Variable
= Mass Flow Rate
•
Frequency Output Process Variable
= Mass Flow Rate
•
AO Cutoff
= 15 g/sec
•
Mass Flow Cutoff
= 10 g/sec
Result:
•
If the mass flow rate drops below 15 g/sec but not below 10 g/sec:
-
The mA output will report zero flow.
-
The frequency output will report the actual flow rate.
•
If the mass flow rate drops below 10 g/sec, both outputs will report zero flow.
Integrate the meter with the control system
88
Micro Motion
®
9739 MVD Transmitters