Siemens simatic et200sp Manual page 36

Reading and processing measured values
6.1 Basics for reading measured values
Initial startup of the module
After the first startup or restart of the module, the parameters are transferred to the module.
You can preset a user data variant in the parameters of the hardware configuration. This
remains in effect until a different user data variant is selected in the output data (byte 0). This
allows input user data to be modified dynamically according to the requirements of the
process.
The user data variant defined in parameter data record 128 is used under the following
conditions:
● A "0" is written in byte 0 in the output data of a user data variant.
● Byte 0 in the output data of a user data variant contains an invalid value:
– Coding of the user data variant not available
– Available address space is not sufficient for the selected user data variant.
Current measured values become "0"
The current and all other measured values based on it are suppressed (or set "0") in the data
records and in the user data in the following cases:
● The incoming current of the current transformer is less than the configured "Low limit for
measuring current" parameter
● Incoming secondary current at the channel is higher than 12 A
The following measured values and derived measured variables of the phase involved
become "0":
● Effective current value
● Active power
● Reactive power
● Apparent power
● Neutral conductor current
● Phase angle
● Power factor
A floating mean value is formed from the power values. These only become "0" after a
corresponding time. The operating hours counter and the energy counter for active, reactive
and apparent energy of the reset phase stops counting.
Substitute value behavior
The substitute values for input values of the AI Energy Meter 480VAC ST amount to "0".
36
or
See "Selecting the module versions (Page 26)".
Analog input module AI Energy Meter 480VAC ST (6ES7134-6PA20-0BD0)
Manual, 12/2015, A5E36061895-AA