Effect On Analog Value Representation; Effect Of The Supply Voltage And The Operating State On Analog Input Values; Effect Of The Value Range On The 2Ai U St Analog Input - Siemens SIMATIC 6ES7134-4FB01-0AB0 Manual

Analog value representation

4.4 Effect on analog value representation

4.4 Effect on analog value representation
4.4.1

Effect of the supply voltage and the operating state on analog input values

The input values of the analog modules are dependent on the supply voltage for
electronics/encoders and on the operating state of the PLC (CPU of the DP master). This is
illustrated by the table below.
Table 4-6
Operating state of the PLC
(CPU of the DP master)
POWER ON
POWER ON
POWER OFF
4.4.2

Effect of the value range on the 2AI U ST analog input

The way electronic modules respond to analog inputs depends on where the input values fall
within the value range. This is illustrated by the table below.
Table 4-7 Response of the analog modules, depending on where the analog input value falls within the range of values
Measured value within ...
Nominal range
Over-/underrange
Overflow
Underflow
Prior to parameter assignment, or with
incorrect parameter assignment
With product version 1 of the 2 AI U ST, the following applies: If the parameter setting error diagnostic message is
*
triggered because the parameters have been assigned incorrectly (e.g., wire break in measuring range ± 20 mA), the SF
LED on the module lights up and the diagnostics can be evaluated. With this status, the correct input values are sent to the
DP master.
18
Relationship between the analog input values for the operating state of the PLC (CPU of
the DP master) and the supply voltage L+
Supply voltage L+ on
ET 200S (power
RUN L+ present
L+ missing
STOP L+ present
L+ missing
- L+ present
L+ missing
Input value in SIMATIC S7 format
Measured value
Measured value
7FFF
H
8000
H
7FFF
H
*
Input value of the electronic module with analog
inputs (evaluation possible on the CPU of the
module)
Process values
7FFF until first conversion after startup, or
H
after assignment of parameters for the module
is completed.
7FFF
H
Process value
7FFF
H
-
-
Input value in SIMATIC S5 format
Measured value
Measured value
End of the overshoot range +1 plus
overflow bit
End of the underrange -1 plus overflow
bit
7FFF
2AI U ST analog electronic module (6ES7134-4FB01-0AB0)
DP master)
H
Manual, 04/2007, A5E01076000-01