Hello, I have a misunderstanding about Profibus telegrams between G120 (starter) and S7-400

The words sent from the VFD to PLC as like (Actual speed, torque actual value, status words ….etc)

I want to know,what is the units of these words by default?is by percentage (%) or by real unit like (Rpm, Nm, Volts…etc)

For my case I wants the value to be sent by percentage relatively to parameter P2000, P2001, P2002, P2003

But I want to be sure if:

• Is it by default, program send the value in real value (Rpm, Nm, Volts…etc) and I should activate another parameter to make it send the values by percentage?
• Or is it by defaults send the output of G120 scaled automatically with default value of P2000, P2001, P2002, and the output value are in percentage?

Thank you

Hello,

BTW which is CU unit?

p2000 rpm, p2001 Vrms, p2002 Arms, p2003 Nm etc. etc. are reference values which units can be select by p0505 which are in ratio to their values set in respective parameters. User need to output values in % of reference values by setting parameters & as per logic requirement, e.g. 4000H =  100% for WORD type & 4000 0000H =  100% = DOUBLE WORD e.g. if p2000 = 1500 RPM then value displayed in r0021 is in RPM which is scaled to value set in p2000 same with current i.e. motor current r0027 is displayed in Arms which is calculated value scaled to value set in p2002.

In PLC user need to convert these values as per requirement e.g. as reference values in % or real values as per data received from drive.

For more details please refer below manuals.

SINAMICS G120 Control Units CU240B-2/CU240E-2

SINAMICS G120 Control Units CU250S-2

SINAMICS G120 CU230P-2 Control Units

Hope this helps.

Thanks for answer

i still have this confusing between scaling parameter P514... p524

and the referance values P2000 .. P2003

which one is taken on consideration for scaling the value of speed torque power ... etc

Hello,

parameters p2000..p2006 are for let's say global scaling, it is reference for all parameters in rpm / Nm / etc. In parameters p519..p524 you can define scaling for individual parameters. If you want to scale individual parameter differently from global scaling.

Moreover, you have at some points possibility of scaling, f.e. p1071 for main speed setpoint, p1138 for ramp-up in RFG, etc.

With regards

Martin

Thank you very much for the answer, i am now understand much better,

please i have two things i would like to know , 

1- can you give me the correct step the scale parameter using P2000 ...P2006 , like; what is the relation of p340 with that

2- if i want to scale a specefic parameter like speed, how i can do that  using parameters (p519..p524)

Thank you