Emerson Process Management Zero And Span Adjustments, Rerange Procedure, Rosemount 2088 and

Reference Manual

00809-0100-4690, Rev EA March 2007

Rosemount 2088 and 2090

ZERO AND SPAN ADJUSTMENTS

NOTE

If either the alarm or security jumper is dislodged or removed from its position the transmitter reverts to default alarm or security settings of: Alarm: Output high; Security: Off

The smart Rosemount 2088 is equipped with local zero and span adjustment buttons. The buttons are located on the top of the transmitter beneath the certifications label. Use the zero and span adjustments to set the 4 and 20 mA output points.

Rerange Procedure

Figure 3-12. Local Zero and Span Adjustments

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

1.Loosen the screw holding the nameplate on top of the transmitter housing and rotate the nameplate to expose the zero and span buttons (see Figure 3-12).

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.

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.

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 “ON” 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 3-11 on page -14 for the proper placement of the transmitter security jumper.

Span and Zero Adjustment Buttons

3-15