Emerson Process Management 2051 Carbon Monoxide Alarm User Manual


 
Quick Installation Guide
00825-0100-4101, Rev EA
June 2010
Rosemount 2051
13
STEP 6: TRIM THE TRANSMITTER
NOTE
Transmitters are shipped fully calibrated per request or by the factory default of full scale
(span = upper range limit).
Zero Trim
A zero trim is a single-point adjustment used for compensating mounting position effects.
When performing a zero trim, ensure that the equalizing valve is open and all wet legs are
filled to the correct level.
There are two methods to compensate for mounting effects:
Field Communicator
Transmitter Zero Adjustment Buttons
Select the appropriate method and follow instructions below.
Using the Field Communicator
If zero offset is within 3% of URL, follow the “Using the Field Communicator” instructions
below. This zero trim will affect the 4-20 mA value, the HART PV, and the display value.
Using the Transmitter Zero Adjustment Buttons
Using the Transmitter Zero Adjustment Buttons, the Lower Range Value (LRV) will be set to
the pressure applied to the transmitter. This adjustment will affect the 4-20 mA value only.
Perform the following steps to perform a rerange using the zero adjustment buttons.
1. Loosen the certifications label screw and slide the label to expose the zero adjustment
buttons. See Figure 9.
2. Set the 4 mA point by pressing the zero button for 2 seconds. Verify that the output is 4
mA. The optional LCD will display ZERO PASS.
Figure 9. Zero and Span buttons
HART Fast Keys Steps
1, 2, 3, 3, 2 1. Equalize or vent the transmitter and connect Fieldbus communicator.
2. At the menu, input the Fast Key sequence.
3. Follow the commands to perform a zero trim.
ZeroSpan
4101_QIG_RevEA.fm Page 13 Tuesday, June 29, 2010 9:26 AM