Rosemount 848T

Reference Manual

00809-0100-4697, Rev EA October 2011

Figure D-6. Input Selector Function Block Application Example (SEL_TYPE = max)

IN1 = 126 °F

 

 

Input Selector

 

 

 

 

 

 

 

 

IN2 = 118 °F

 

 

(ISEL) Function

 

 

 

 

 

 

 

 

 

 

Block

 

 

 

IN3 = 104 °F

 

 

 

 

To Another

 

 

OUT = 140 °F

 

 

 

IN4 = 107 °F

 

 

 

 

 

 

 

 

 

 

IN5 = 112 °F

 

 

 

 

 

 

Function Block

 

 

 

 

 

 

 

IN6 = 115 °F

 

 

 

 

 

 

 

 

 

 

 

 

 

 

IN7 = 130 °F

 

 

 

 

 

 

 

 

 

 

 

 

 

 

IN8 = 140 °F

 

 

SEL_TYPE = max

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Figure D-7. Input Selector Function Block Application Example (SEL_TYPE = average) AVG_USE = 6

IN1 = 126 °F

 

 

Input Selector

 

 

 

 

 

 

 

 

IN2 = 118 °F

 

 

(ISEL) Function

 

 

 

 

 

 

 

 

 

 

Block

 

 

 

IN3 = 104 °F

 

 

 

 

To Another

 

 

OUT = 118 °F

 

 

 

IN4 = 107 °F

 

 

 

 

 

 

 

 

 

 

IN5 = 112 °F

 

 

 

 

 

 

Function Block

 

 

 

 

 

 

 

IN6 = 115 °F

 

 

AVG_USE = 6

 

 

 

 

 

 

 

 

IN7 = 130 °F

 

 

 

 

 

 

 

 

 

 

IN8 = 140 °F

 

 

SEL_TYPE = avg

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

To determine OUT for a 6-input reading, read all eight, sort in numerical order, drop the highest and lowest values, and calculate the average.

 

 

107-------------------------------------------------------------------------------------------+112 + 115 + 118 + 126 + 130 = 118°F

 

 

6

ISEL Block

 

 

Troubleshooting

 

 

Symptom

Possible Causes

Corrective Action

Mode will not leave OOS

Target mode not set.

Set target mode to something other than OOS.

 

Configuration error

BLOCK_ERR will show the configuration error bit set. SELECT_TYPE must be set to

 

 

a valid value and cannot be left at 0.

 

Resource block

The actual mode of the Resource block is OOS. See Resource Block Diagnostics for

 

 

corrective action.

 

Schedule

Block is not scheduled and therefore cannot execute to go to Target Mode. Typically,

 

 

BLOCK_ERR will show “Power-Up” for all blocks that are not scheduled. Schedule the

 

 

block to execute.

Status of output is BAD

Inputs

All inputs have Bad status

 

OP selected

OP_SELECT is not set to 0 (or it is linked to an input that is not 0), and it points to an

 

 

input that is Bad.

 

Min good

The number of Good inputs is less than MIN_GOOD.

 

Block is in OOS mode

Change mode to Auto

Block alarms will not work.

Features

FEATURES_SEL in the resource block does not have Alerts enabled. Enable the

 

 

Alerts bit.

 

Notification

LIM_NOTIFY in the resource block is not high enough. Set equal to MAX_NOTIFY.

 

Status Options

STATUS_OPTS has Propagate Fault Forward bit set. This should be cleared to cause

 

 

an alarm to occur.

Cannot set HI_LIMIT,

Scaling

Limit values are outside the OUT_SCALE.EU0 and OUT_SCALE.EU100 values.

HI_HI_LIMIT, LO_LIMIT,

 

Change OUT_SCALE or set values within range.

LO_LO_LIMIT

 

 

D-20

Page 110
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Emerson 848T manual Isel Block Troubleshooting

848T specifications

The Emerson 848T is a state-of-the-art temperature transmitter designed for accurate and reliable temperature measurement in various industrial applications. This device has gained recognition for its advanced features and robust performance, making it a popular choice among engineers and technicians in the field.

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