Writing To The Holding Registers - Siemens SIMATIC S7-1200 Manual

5 Operating the Application Examples
5.2.2

Writing to the holding registers

The holding registers (purple font) are written according to the selection of the
corresponding register in the drop-down menu.
Depending on the selected display, you can access all writable registers from
Table 3-1
"Overview" display:

D001: Default set value

D102: Preferred running direction

D105: Internal parameter set
Figure 5-4
If the start fan (from:) to be addressed or the register to be written changes, it will
be read automatically (blue background) and the read value is taken over from the
input/output field (yellow background) to be written to. You can now edit the value
within the specified limits and transfer the value to all fans in the from/to area using
the "Write" button.
Subsequently, the selected start fan register (from:) is automatically read again.
If the transfer has been successful, the read value corresponds to the written value.
Certain holding registers (see
in order to be transferred to the RAM, they require the "Param." function to be
executed in the "Reset" (D000) holding register. These parameters have the edit
value field displayed with an orange background:
If the register access requires authorization with a password (see
has not been transferred yet, error code 16#8388 ("Error in the response of the
slave to write request") occurs in the status evaluation.
Note When writing the default set value (D001), make sure that all fans to be
addressed (from to) must be in the same operating mode (Control [%] or speed
control [rpm]).
The default set value is otherwise interpreted incorrectly and the fans will be
controlled differently!
Controlling several fans (ebm-papst) via Modbus RTU
Entry ID: 109476801, V2.0,
in the "Fan view" display and only the following registers in the
Table
09/2018
3-1) are first written to the fan's EEPROM and
Table 3-1) that
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