
6
Reference Manual
00809-0100-4808, Rev DA
Transmitter Functions
October 2016
Transmitter Functions
Figure 2-2. Rosemount 3051N Transmitter with Optional LCD Display Meter
Note
Security jumper not installed = not write protected
Alarm jumper not installed = high alarm
2.6
Commissioning transmitter with a HART-based
communicator
Commissioning consists of testing the transmitter and verifying transmitter configuration data. You may
commission Rosemount 3051N Transmitters either before or after installation. Commissioning the
transmitter on the bench before installation using a HART-based Communicator ensures that all
transmitter components are in good working order and acquaints you with the operation of the device.
To commission on the bench, connect the transmitter and the communicator as shown in
Figure 2-3
.
Make sure the instruments in the loop are installed in accordance with intrinsically safe or nonincendive
field wiring practices before connecting a communicator in an explosive atmosphere. Connect the
communicator leads at any termination point in the signal loop. It is most convenient to connect them to
the terminals labeled “COMM” on the terminal block. Connecting across the “TEST” terminals will
prevent successful communication. To avoid exposing the transmitter electronics to the plant
environment after installation, set all transmitter jumpers during the commissioning stage on
the bench.
For 4–20 mA transmitters, you will need a power supply capable of providing 10.5 to 55 V dc at the
transmitter, and a meter to measure output current. To enable communication, a resistance of at least
250 ohms, but within the transmitter load limitations (see
Figure 3-7 on page 35
) must be present
between the communicator loop connection and the power supply. Do not use inductive-based
transient protectors with the Rosemount 3051N Transmitter.
2.6.1
Setting the loop to manual
Whenever you are preparing to send or request data that would disrupt the loop or change the output of
the transmitter, you must set your process application loop to manual. The HART Communicator will
prompt you to set the loop to manual when necessary. Keep in mind that acknowledging this prompt
does not set the loop to manual. The prompt is only a reminder; you have to set the loop to manual
yourself as a separate operation.