6.6 DPConf Configuration - PV1, Continued

Damping

Background

Adjust the damping time constant for Differential Pressure (PV1) to reduce the output noise. We suggest that you set the damping to the smallest value that is reasonable for the process.

The damping values (in seconds) for PV1 are:

0.00d, 0.16, 0.32, 0.48,

1.0, 2.0, 4.0, 8.0, 16.0, and 32.0

d Factory setting.

The electrical noise effect on the output signal is partially related to the turndown ratio of the transmitter. As the turndown ratio increases, the peak-to-peak noise on the output signal increases. You can use this formula to find the turndown ratio using the pressure range information for your transmitter.

Upper Range Limit

Turndown Ratio = (Upper Range Value – Lower Range Value)

Example: The turndown ratio for a 400 inH2O transmitter with a range of

0 to 50 inH2O would be:

4008

Turndown Ratio = (50 – 0) = 1 or 8:1

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Honeywell SMV 3000 user manual Damping Background