Rosemount 8712, Reference Manual

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Reference Manual
00809-0100-4664, Rev BA
January 2010
Rosemount 8712
A-4
Flow Limits (2):
Activates switch closure output when the transmitter measures a flow rate
that meets the conditions established for this alert. There are two
independent flow limit alerts that can be configured as discrete outputs.
Totalizer Limit:
Activates switch closure output when the transmitter measures a total flow
that meets the conditions established for this alert.
Diagnostic Status:
Activates switch closure output when the transmitter detects a condition
that meets the configured criteria of this output.
Optional Digital Input Function (AX option)
Externally powered at 5 to 24 V DC, transistor switch closure up to 3 W to
indicate either:
Net Total Reset:
Resets the net totalizer value to zero.
Positive Zero Return (PZR):
Forces outputs of the transmitter to zero flow. Activated by applying a
contact closure.
Security Lockout
Security lockout jumper on the electronics board can be set to deactivate all
LOI and HART-based communicator functions to protect configuration
variables from unwanted or accidental change.
Output Testing
Analog Output Test
Transmitter may be commanded to supply a specified current between
3.75 and 23.25 mA
Pulse Output Test
Transmitter may be commanded to supply a specified frequency between
1 pulse/ day and 10,000 Hz
Turn-on Time
5 minutes to rated accuracy from power up, 5 seconds from power
interruption
Start-up Time
0.2 seconds from zero flow
Low Flow Cutoff
Adjustable between 0.01 and 38.37 ft/s (0.003 and 11.7 m/s). Below selected
value, output is driven to the zero flow rate signal level.
Overrange Capability
Signal output will remain linear until 110% of upper range value. The signal
output will remain constant above these values. Out of range message
displayed on LOI and the HART Communicator.