Dear experts, 

I have a system consisting of D435+2PD/PN controler and 4 SINAMICS S modules (ALM + AIM + SMM + BM + VSM), and I have to establish communication with external system (not Siemens) via Profibus, and to send data (speed, torque, power, current, voltage ect.). However there is a problem regarding the values of these parameters because I can only read them and send them as DWORD or WORD and not as LREAL, which is a huge problem.
Does anybody have a suggestion on how to send thees parameters as real values via profibus.

Thanks in advance.
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Split from Simotion D435 with Simotion D CX35 and Sinamics drives control system.

ChristophD

Hello,

LREAL is not possible, because this is not supported from the PROFIBUS communication.

ist the same in the communication between drive and PLC, here no LREAL is transfered, only HEX values which are calculated with  a norm value to the LREAL.

You can do this also for your communication.

Regards

Christoph

 Thank you, 

are there any pre-defined norm values for different parameters, because for example if I send temperature of 20.5 degrees Celsius in HEX it's for example 16x00_04_FB_64 which expressed in DEC is some big number, so in order to get initial value of 20.5 I have to divide with some number, is that number defined somewhere or...?

Kaulquappe

Hello Nikivuk,
I think you have a general problem to understand how communication and computers work. All data is transferred as hex bytes. It is a question of the application how it is interpreted. Both applications, sender and receiver, must interpret the data identically.

Regards,
Kaulquappe

 Actually I have problem understanding how it works in Simatcis, and if you would please be so kind and explain me this:

the value of speed for instance is REAL value and can go for example from -500 to 500 rpm, but when I assign this parameter (r21) to some variable for example mySpeed program converts it and I get HEX representation of the speed. How do I convert that value back to the REAL?