Emerson 644 manual Sensor Transducer Block, Analog Input AI Function Block, Damping, Channel

Reference Manual

00809-0400-4728, Rev AA June 2011

Rosemount 644

Table 3-1.

RB.RECOMMENDED_ACTION

Sensor Transducer Block

		Failed/Maint/Advise	Recommended Action
	Alarm Type	Active Event	Text String
	None	None	No action required
		NV Writes Deferred	Non-volatile writes have been deferred, leave
	Advisory		the device powered until the advisory goes
			away
		Configuration Error	Re-write the Sensor Configuration
		Primary Value	Confirm the operating range of the applied
		Degraded	sensor and/or verify the sensor connection and
Alerts	Maintenance		device environment
		Calibration Error	Retrim the device
		Secondary Value	Verify the ambient temperature is within
PlantWeb		Degraded	operating limits
		Electronics Failure	Replace the Device
		HW / SW Incompatible	Verify the Hardware Revision is compatible with
			the Software Revision
		NV Memory Failure	Reset the device then download the Device
	Failed		Configuration
		Primary Value Failure	Verify the instrument process is within the
			Sensor range and / or confirm sensor
			configuration and wiring.
		Secondary Value	Verify the ambient temperature is within
		Failure	operating limits

NOTE

When the engineering units of the XD_SCALE are selected, the engineering units in the Transducer Block change to the same units. THIS IS THE ONLY WAY TO CHANGE THE ENGINEERING UNITS IN THE SENSOR TRANSDUCER BLOCK.

Damping

Analog Input (AI) Function Block

The damping parameter in the Transducer Block may be used to filter measurement noise. By increasing the damping time, the transmitter will have a slower response time, but will decrease the amount of process noise that is translated to the Transducer Block Primary Value. Because both the LCD and AI Block get input from the Transducer Block, adjusting the damping parameter will effect both blocks.

NOTE

The AI Block has it's own filtering parameter called PV_FTIME. For simplicity, it is better to do filtering in the Transducer Block as damping will be applied to primary value on every sensor update. If filtering is done in AI block, damping will be applied to output every macrocycle. The LCD will display value from Transducer block.

Configure the AI block

A minimum of four parameters are required to configure the AI Block. The parameters are described below with example configurations shown at the end of this section.

CHANNEL

Select the channel that corresponds to the desired sensor measurement. The 644 measures both sensor temperature (channel 1) and terminal temperature (channel 2).

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