2 standard analog input block (ai), 1 operating modes, 2 set the parameter and units – Hach-Lange SI792 C, SI792x C, SI792x C-FF, SI792x C-PA User Manual User Manual

Page 49: Operation—foundation fieldbus

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Operation—Foundation Fieldbus

47

6.2.2 Standard analog input block (AI)

Three Analog Input Function Blocks provide for cyclic transmission of
measured values (currently measured value with status, alarm limits,
freely selectable process parameter).

6.2.2.1 Operating modes

Use the MODE_BLK parameter to set the following operating modes:

OOS—out of service. If not write-protected, access to all
parameters is allowed.

MAN—manual

Auto—online, normal state

6.2.2.2 Set the parameter and units

Use CHANNEL to set the measured parameter and units (

Table 8

). The

corresponding measurement unit is selected in the UNITS
subparameter of XD_SCALE (

Table 9 on page 49

).

Table 8 Measurement parameters and units

Channel

Parameter

Unit

Unit value

1

Conductivity

µS/cm

1586

mS/cm

1302

S/cm

1299

2

Concentration

% (percent)

1342

3

Temperature

°C

1001

°F

1002

4

Salinity

per mill

2003

5

Resistance

M

Ω/cm

1587

6

Cell constant

cm

-1

2004

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