Rosemount Model 1195/ProPlate/Mass ProPlate
5-20
Analog Output Trim
The Analog Output Trim commands allow you to adjust the current
output at the 4 and 20 mA points to match the plant standards. This
command adjusts the digital to analog signal conversion (see Figure 5-6
on page 5-17).
Digital to Analog Trim
To perform a digital-to-analog trim with a HART communicator,
perform the following procedure.
1. From the HOME screen, select 1 Device setup, 2 Diag/Service, 3
Calibration, 4 D/A trim. Select “OK” after you set the control loop
to manual (see <Bold>Setting the Loop to Manual on page -5).
2. Connect an accurate reference ammeter to the flowmeter at the
“Connect reference meter” prompt. To do so, connect the positive
lead to the positive terminal and the negative lead to the test
terminal in the flowmeter terminal compartment, or shunt the
flowmeter power through the reference meter at some point.
3. Select “OK” after connecting the reference meter.
4. Select “OK” at the “Setting fld dev output to 4 mA” prompt.
5. The flowmeter outputs 4.00 mA.
6. Record the actual value from the reference meter, and enter it at
the “Enter meter value” prompt.
7. The communicator prompts you to verify whether or not the output
value equals the value on the reference meter.
8. Select 1 Yes if the reference meter value equals the flowmeter
output value, or 2 No if it does not.
9. If you select 1 Yes, proceed to Step 7.
10. If you select 2 No, repeat Step 5.
11. Select “OK” at the “Setting fld dev output to 20 mA” prompt, and
repeat Steps 5 and 6 until the reference meter value equals the
flowmeter output value.
12. Select “OK” after you return the control loop to automatic control.
Digital to Analog
Trim Using Other Scale
The Scaled D/A Trim command matches the 4 and 20 mA points to
a user-selectable reference scale other than 4 and 20 mA (1 to 5 volts
if measuring across a 250 ohm load, or 0 to 100 percent if measuring
from a DCS, for example). To perform a scaled D/A trim, connect an
accurate reference meter to the flowmeter and trim the output
signal to scale as outlined in the Output Trim procedure.
HART Comm. 1, 2, 3, 2, 1
HART Comm. 1, 2, 3, 2, 2
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