Application Specific Configuration - Emerson Rosemount 3051 Manual

Manual
00809-0100-4007
2.6

Application specific configuration

2.6.1 Configuring for flow rate
With the flow rate configuration, you can create a relationship between the pressure units
and user-defined flow units. By defining a pressure at a specific flow rate, the transmitter
will perform a square root extraction to convert the pressure reading to a linear flow rate
output.
Flow rate configuration includes the following parameters:
• Flow units: user-specified units for flow rate
• Entered flow rate: user-specified flow rate
• Pressure at flow rate
Configure for flow rate with a communication device
Procedure
Go to Device Settings → Output → Flow → Setup → Configure Flow.
Configuring low flow cut-off
Emerson highly recommends using the low flow cut-off function to have a stable output
and avoid problems due to process noise at a low flow or no flow condition.
There are two key definitions to aid in understanding low flow cut-off:
Pressure cut-off
value
Pressure cut-in
value
Configure low flow cut-off with a communication device
Procedure
Go to Device Settings → Output → Flow → Setup → Low Flow Cutoff
Configuring for flow rate example
Use a differential pressure transmitter in conjunction with an orifice plate in a water flow
application where the full-scale flow rate is 20,000 US gallons per hour with a differential
pressure of 100 inH
flow cut-off will be set to 0.5 inH
Based on this information, the configuration would be:
(2) You can use the DP Flow Sizing and Selection Tool
flow.
Emerson.com/Rosemount
(2) : user-specified pressure at the entered flow rate.
The pressure at which the field device will stop measuring the flow rate.
If the measured pressure is less than the cut-off value, the device will
calculate the flow rate to be zero.
The pressure at which the field device will begin measuring the flow
rate. If the measured pressure is more than the cut-in value, the device
will begin measuring flow rate.
O at 68 °F. The pressure cut-off and pressure cut-in values for the low
2
O at 68 °F.
2
to help you establish the relationship between pressure and
Configuration
March 2023
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