P0742 - Profibus Reading #3; P0743 - Profibus Reading #4; P0744 - Profibus Reading #5; P0745 - Profibus Reading #6 - WEG CFW500 User Manual

Speed for PROFIdrive profile:
If the used profile is the PROFIdrive, both the speed reference and the motor speed must be indicated as a
value proportional to the drive maximum speed, programmed through P0134:
Value via Profibus = 0000h (0 decimal)

Value via Profibus = 4000h (16384 decimal) → Speed = maximum speed (P0134)

Intermediary speed values in rpm can be obtained using this scale. For instance, if P0134 is programmed for 30
Hz and the motor speed value read via Profibus is 2048 (0800 h), in order to obtain the value in Hz the following
calculation must be done:
16384 => 30 Hz
2048 => speed in Hz
Speed in Hz = 30 × 2048
Speed in Hz = 3.75 Hz
The same calculation applies for the transmission of speed reference values. Negative speed values indicate
reverse speed direction.
NOTE!
For the reference writing in the drive, the values are converted and written in the parameter

P0685.
The reference writing does also depend on the bit 6 of the PROFIdrive control word (P0967).

If this parameter is changed, the slave will assume the new configuration only when there is no

cyclic communication with the master.
P0742 – PROFIBUS READING #3
P0743 – PROFIBUS READING #4
P0744 – PROFIBUS READING #5
P0745 – PROFIBUS READING #6
P0746 – PROFIBUS READING #7
Range: 0 to 1199
Properties:
DP
Access groups via HMI:
Description:
These parameters allow programming the content of the input words 3 a 83 to 10 (input: drive sends to the
master). By using these parameters it is possible to program the number of another parameter whose content
must be made available at the network master input area.
If, for instance, one wants to read from the CFW500 frequency inverter the motor current in Amps, one must
program the value 3 in one of these parameters, because the parameter P0003 is the one that contains this
information. It is worthwhile to remind that the value read from any parameter is represented with a 16 bit word.
Even if the parameter has decimal resolution, the value is transmitted without the indication of the decimal
places. E.g., if the parameter P0003 has the value 4.7A, the value supplied via the network will be 47.
These parameters are used only if the equipment is programmed at the parameter P0922 to use the options 3
to 8 (configuration telegrams 103 to 108). Up to 8 words to be read by the network master can be made
available, according to the selected option.
The first two input words are fixed and represent the status and the motor speed.
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16384
NET
→ Speed = 0 Hz
Default: 0 (disabled)