Emerson Process Management 1500 manual 8 mA output fault actions and values, Fault action

Models: 1500

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Table 4-8mA output fault actions and values

Required Transmitter Configuration

4.5.4Configuring the fault action, fault value, and last measured value timeout

Note: If the mA output is configured for valve control, it cannot be used to report alarm status, and the mA output will never go to fault levels.

If the transmitter encounters an internal fault condition, it can indicate the fault by sending a preprogrammed output level to the receiving device. You can specify the output level by configuring the fault action. Options are shown in Table 4-8.

By default, the transmitter immediately reports a fault when a fault is encountered. You can configure the transmitter to delay reporting a fault by changing the last measured value timeout to a non-zero value. During the fault timeout period, the transmitter continues to report its last valid measurement.

Table 4-8mA output fault actions and values

Fault action

Fault output value

 

 

Upscale

21–24 mA (default: 22 mA)

 

 

Downscale

1.0–3.6 mA (default: 2.0 mA)

 

 

Internal zero

The value associated with 0 (zero) flow, as determined by URV and LRV values

 

 

None(1)

Tracks data for the assigned process variable; no fault action

 

 

(1)If the mA output fault action is set to None, the digital communications fault action should also be set to None. See Section 6.12.1.

Fault actionFault output value4.5.5Configuring added damping CAUTION

Setting the fault action to NONE may result in process error due to undetected fault conditions.

To avoid undetected fault conditions when the fault action is set to NONE, use some other mechanism such as digital communications to monitor device status.

4.5.5Configuring added damping

A damping value is a period of time, in seconds, over which the process variable value will change to reflect 63% of the change in the actual process. Damping helps the transmitter smooth out small, rapid measurement fluctuations:

A high damping value makes the output appear to be smoother because the output must change slowly.

A low damping value makes the output appear to be more erratic because the output changes more quickly.

The added damping parameter specifies damping that will be applied to the mA output. It affects the measurement of the process variable assigned to the mA output, but does not affect other outputs.

When you specify a new added damping value, it is automatically rounded down to the nearest valid value. Note that added damping values are affected by the Update Rate parameter (see Section 6.7).

Note: Added damping is not applied if the mA output is fixed (i.e., during loop testing) or is reporting a fault.

Before You Begin

Using ProLink II

Flowmeter Startup

Required Configuration

Configuration and Use Manual

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Emerson Process Management 1500 manual 8 mA output fault actions and values, 4.5.5Configuring added damping, Fault action