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Data format -4, Data format – Rockwell Automation 1797-IRT8 FLEX Ex Thermocouple/RTD/mV Input Module User Manual User Manual

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Publication 1797-6.5.2 - February 2001

2-4 Understanding Configurable FLEX Ex Thermocouple/RTD/mV Input Module Features

Choose the best input filter cutoff in your programming software.

Data Format

You must choose a module data format in your user program. Select
the format by setting bits as shown below. Note that this parameter
affects channel accuracy.

o

C,

o

F and

o

K will have formats appropriate to the selected

thermocouple or RTD range (e.g. -xxxx to +xxxx with 1 decimal place
implied - 3500 = 350.0). For Cu10 RTD, 2 decimal points are implied.

If using mV, data format defaults to -4000 to +10000 (2 decimal points
implied (e.g. -40 to 100.00). If using W mode selection, data format
defaults to 0 to 5000 (1 decimal point implied, e.g. 0.- to 500.0).

In the thermocouple and RTD modes, if unused data formats are

chosen, the module will default to

o

C.

Input Filter Cutoff bits

Bit

02

01

00

Definition

0

0

0

Hardware filtering only (default filtering) 600Hz (1.7ms)

0

0

1

40Hz

(25ms)

0

1

0

10Hz

(100ms)

0

1

1

4Hz

(250ms)

1

0

0

2Hz

(500ms)

1

0

1

1Hz

(1s)

1

1

0

0.5Hz

(2s)

1

1

1

0.2Hz

(5s)

Data format – module defaults to –4000 to 10000 in millivolt mode, and 0 to 5000 in ohms mode

Bit

11

10

09

08

Data type for channels 0-7

0

0

0

0

°C

0

0

0

1

°F

0

0

1

0

×K

0

0

1

1

–32767 to +32767

0

1

0

0

0 to 65535

0101 through 1111 not used