Reading Measured Values From User Data Cyclically - Siemens SIMATIC ET 200SP Manual

Reading and processing measured values

6.3 Reading measured values from user data cyclically

6.3 Reading measured values from user data cyclically
Requirement
● STEP 7 is open.
● AI Energy Meter 400VAC ST is configured.
Scaling of measured values in the user data
Since the value range of 16-bit values is often smaller than the value range of the physical
value, a scaling factor is supplied together with the basic value in the user data for the
respective measured or calculated values. You determine the actual value of the measured
variable with the following formula:
Actual value of measured quantity = measured value in the user data x 10
Procedure
To read measured values from the user data cyclically, proceed as follows:
1. Read the relevant measured value from the input data.
2. Observe the scaling factor at scaled measured values and convert the read measured
value using the scaling factor.
Example
The user data variant 254 (FE
400VAC ST. The measured value for "Current L1" should be read.
Table 6- 1 Total power L1L2L3
Byte Allocation
0 User data variant
1 Quality information = QQ
2 ... 3 Current L1
4 ... 5 Current L2
6 ... 7 Current L3
: :
24 Scaling current L1
25 Scaling current L2
26 Scaling current L3
: :
31 Scaling total reactive energy L1L2L3
34
) "Total power L1L2L3" is configured on the AI Energy Meter
H
Data type
BYTE
I U I U I U BYTE
1 3 3 2 2 1 1
UINT
UINT
UINT
:
USINT
USINT
USINT
:
USINT
Analog input module AI Energy Meter 400VAC ST (6ES7134-6PA01-0BD0)
Unit Value range
- 254 (FE )
H
Bit string qq xx xx xx
1 mA 0 ... 65535
1 mA 0 ... 65535
1 mA 0 ... 65535
: :
- 0 ... 255
- 0 ... 255
- 0 ... 255
: :
- 0 ... 255
Manual, 10/2017, A5E36061895-AB
scaling factor
Measured value ID
-
-
66007
66008
66009
:
-
-
-
:
-