Emerson 3051N User Manual

Reference Manual 

00809-0100-4808, Rev CA
June 2008

2-11

Rosemount 3051N

To rerange the transmitter using the span and zero buttons, perform the 
following procedure:

1.

Loosen the screw holding the label on top of the transmitter housing, 
and rotate the label to expose the zero and span buttons (see Figure 
2-6).

2.

Using a pressure source with an accuracy three to ten times the 
desired calibrated accuracy, apply a pressure equivalent to the lower 
range value to the high side of the transmitter.

3.

To set the 4 mA point, press and hold the zero button for at least two 
seconds, then verify that the output is 4 mA. If a meter is installed, it 
will display ZERO PASS.

4.

Apply a pressure equivalent to the upper range value to the high side 
of the transmitter.

5.

To set the 20 mA point, press and hold the span button for at least two 
seconds, then verify that the output is 20 mA. If a meter is installed, it 
will display SPAN PASS.

NOTE
If the transmitter security jumper is in the 

 position, or if the local zero and 

span adjustments are disabled through the software, you will not be able to 
make adjustments to the zero and span using the local buttons. Refer to 
Figure 2-1 for the proper placement of the transmitter security jumper. Or refer 
to “Local Span and Zero Control (Local Keys)” in Section 2 for instructions on 
how to enable the span and zero buttons.

FIGURE 2-6. Local Zero and
Span Adjustments.

After you rerange the transmitter using the span and zero adjustments, it is 
possible to disable the adjustments to prevent further reranging. Refer to 
“Local Span and Zero Control (Local Keys)” below for
more information.