Rosemount 848T

Reference Manual

00809-0100-4697, Rev EA October 2011

Table D-1. Analog Input Function Block Parameters

Number

Parameter

Units

Description

10

XD_SCALE

None

The high and low scale values, engineering units code, and number of digits to

 

 

 

the right of the decimal point associated with the channel input value. The

 

 

 

XD_SCALE units code must match the units code of the measurement channel in

 

 

 

the transducer block. If the units do not match, the block will not transition to MAN

 

 

 

or AUTO.

11

OUT_SCALE

None

The high and low scale values, engineering units code, and number of digits to the

 

 

 

right of the decimal point associated with OUT when L_TYPE is not direct.

12

GRANT_DENY

None

Options for controlling access of host computers and local control panels to

 

 

 

operating, tuning, and alarm parameters of the block. Not used by device.

13

IO_OPTS

None

Allows the selection of input/output options used to alter the PV. Low cutoff enabled

 

 

 

is the only selectable option.

14

STATUS_OPTS

None

Allows the user to select options for status handling and processing. The options

 

 

 

supported in the AI block are the following:

 

 

 

Propagate fault forward

 

 

 

Uncertain if limited

 

 

 

Bad if limited

 

 

 

Uncertain if Manual mode.

15

CHANNEL

None

The CHANNEL value is used to select the measurement value. Configure the

 

 

 

CHANNEL parameter before configuring the XD_SCALE parameter. Refer to Table

 

 

 

3-5 on page 3-11.

16

L_TYPE

None

Linearization type. Determines whether the field value is used directly (Direct), is

 

 

 

converted linearly (Indirect), or is converted with the square root (Indirect Square

 

 

 

Root).

17

LOW_CUT

%

If percentage value of transducer input fails below this, PV = 0.

18

PV_FTIME

Seconds

The time constant of the first-order PV filter. It is the time required for a 63% change

 

 

 

in the PV or OUT value.

19

FIELD_VAL

Percent

The value and status from the transducer block or from the simulated input when

 

 

 

simulation is enabled.

20

UPDATE_EVT

None

This alert is generated by any change to the static data.

21

BLOCK_ALM

None

The block alarm is used for all configuration, hardware, connection failure or system

 

 

 

problems in the block. The cause of the alert is entered in the subcode field. The first

 

 

 

alert to become active will set the Active status in the Status parameter. As soon as

 

 

 

the Unreported status is cleared by the alert reporting task, another block alert may

 

 

 

be reported without clearing the Active status, if the subcode has changed.

22

ALARM_SUM

None

The summary alarm is used for all process alarms in the block. The cause of the

 

 

 

alert is entered in the subcode field. The first alert to become active will set the

 

 

 

Active status in the Status parameter. As soon as the Unreported status is cleared

 

 

 

by the alert reporting task, another block alert may be reported without clearing the

 

 

 

Active status, if the subcode has changed.

23

ACK_OPTION

None

Used to set auto acknowledgment of alarms.

24

ALARM_HYS

Percent

The amount the alarm value must return within the alarm limit before the associated

 

 

 

active alarm condition clears.

25

HI_HI_PRI

None

The priority of the HI HI alarm.

26

HI_HI_LIM

EU of PV_SCALE

The setting for the alarm limit used to detect the HI HI alarm condition.

27

HI_PRI

None

The priority of the HI alarm.

28

HI_LIM

EU of PV_SCALE

The setting for the alarm limit used to detect the HI alarm condition.

29

LO_PRI

None

The priority of the LO alarm.

30

LO_LIM

EU of PV_SCALE

The setting for the alarm limit used to detect the LO alarm condition.

31

LO_LO_PRI

None

The priority of the LO LO alarm.

32

LO_LO_LIM

EU of PV_SCALE

The setting for the alarm limit used to detect the LO LO alarm condition.

33

HI_HI_ALM

None

The HI HI alarm data, which includes a value of the alarm, a timestamp of

 

 

 

occurrence and the state of the alarm.

34

HI_ALM

None

The HI alarm data, which includes a value of the alarm, a timestamp of occurrence

 

 

 

and the state of the alarm.

35

LO_ALM

None

The LO alarm data, which includes a value of the alarm, a timestamp of occurrence

 

 

 

and the state of the alarm.

D-2

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Emerson 848T Xdscale, Outscale, Ioopts, Statusopts, Channel, Ltype, Lowcut, Pvftime, Fieldval, Alarmhys, Hihipri, Hihilim

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