Emerson Micro Motion 2500, Руководство по конфигурации и использованию

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Restriction
AO Cutoff is applied only if mA Output Process Variable is set to
Mass Flow Rate
,
Volume Flow Rate
, or
Gas Standard Volume Flow Rate . If mA Output Process Variable is set to a different process variable, AO
Cutoff is not configurable, and the transmitter does not implement the AO cutoff function.
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 customer 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.
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.
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.
Integrate the meter with the control system
82 Micro Motion Model 2500 Transmitters with Configurable Input/Outputs