Siemens SINUMERIK 840D sl Function Manual page 27

840Di hardware digital I/Os
Digital inputs/outputs are provided for the SINUMERIK 840Di via the MCI-Board-Extension
module. The following connections are available:
● Two handwheels
● Two probes
● Four digital inputs/outputs
SINUMERIK 840Di analog and digital inputs/outputs
Analog and digital inputs/outputs can be operated on the SINUMERIK 840Di by means of
SIMATIC S7 bus-interface and signal modules, via the PROFIBUS-DP.
PLC I/Os for direct addressing by NCK
Up to 16 bytes for digital input signals and analog input values plus a total of 16 bytes for
digital output signals and analog output values can be addressed directly by the part
program. These bytes must be taken into account when the PLC is configured. They must be
programmed consecutively. They are processed directly by the PLC operating system. As a
result, the time taken to transfer signals between the NC and PLC I/O modules is of an order
of magnitude of 0.5 ms.
Note
The output bytes specified for the NCK may not be write-accessed by the PLC user program,
as the access operations between the NCK and PLC would be uncoordinated.
Comparator inputs
In addition to the digital and analog NCK inputs, 16 internal comparator inputs (comparator
input bytes 1 and 2) are also available.
The signal state of a comparator input is formed by comparing an analog input signal with a
threshold value within a setting data.
Extended Functions
Function Manual, 03/2009, 6FC5397-1BP10-4BA0
Note
The MCI-Board-Extension module is an option for the SINUMERIK 840Di. The pin
assignment of the cable-distributor interface (X121) matches that of the cable distributor
on the SINUMERIK 840D.
Digital and Analog NCK I/Os (A4)
NCK I/O via PLC
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