SOFT STARTER 3WR44 PROFIBUS COMMUNICATION WITH S7400H CPU.

RAKIB

DEAR ALL,
Good day. I am presently working on a project consisting of Siemens s7400h system and Sirius 3wr44 soft starter. the soft starters are all commissioned. now I have to read some data like current, voltage, operating hour etc. the system has y link to convert redundant Profibus network to single network. I have not work on 3wr44 Profibus communication. now can anyone suggest me the procedure to read data from soft starter to H-CPU and write command to the device through y link from the H-CPU. please suggest me elaborately. I have the GSD file. but in the input-output field, there is only 2byte. how can I read all the required data from only 2 bytes. same for the output command. find the attachment containing hardware configuration of the network of H-CPU and soft starter through y link.
Thanks in advance. 
hope to hear from someone expert soon.

Hello RAKIB,

First you cann't read all what you mentioned above from Softstarter. You can only read current.

As you said you have two bytes input and two bytes output.

In page 170 & 171 of the bellow manual, you will found the process image for each bit in DO / DI

https://support.industry.siemens.com/cs/ww/en/view/21772518

To read current, please note that it can be read in bits DI-1.0 to DI1.5 (6 bits) knowing that there's a mistake in the manual (new version)-- Old version is correct (Page 8-24) --
https://www.industry.usa.siemens.com/automation/us/en/industrial-controls/products/solid-state-control/soft-starters/Documents/3RW44%20system%20manual.pdf

To calculate current values from the 6-bits, please see current values section in page 180 of first manual.

I think you may need to make a FC to use for all your softstarter. It's easy. I have made it once and it's working perfect.

Hope this helps.

Dear RAKIB ,

I think (!) the statement above is not completely true..... 

https://support.industry.siemens.com/cs/ww/en/view/21772518
--> see chapter "9.12 Data sets (BS)" of above mentioned 3RW44 manual;

Those data sets/data records can be written / read via SFB 53 "WR_REC" / SFB 52 "RD_REC" ( compare with FAQ https://support.industry.siemens.com/cs/ww/en/view/81666674 which shows reading / writing data records with an S7-1200 CPU)

Example "9.12.11 Data set 94 - Reading measured values"
--> data record 94 byte 22 - 39 contains the following information:
Line-to-line voltage UL1-L2(rms)
Line-to-line voltage UL2-L3(rms)
Line-to-line voltage UL3-L1(rms)
Phase current IL1(rms)
Phase current IL2(rms)
Phase current IL3(rms)

Example "9.12.12 Data set 95 - Reading statistical data"
--> data record 95 byte 4-7 "Operating hours - device"

kind regards

PS: And if you are using PCS7 there exists a "SIRIUS Soft Starter 3RW44 PCS 7 Library" which might ease the access to the information / data you require :-)
See https://support.industry.siemens.com/cs/ww/en/ps/16710

Mr. SIRIUS

Be aware on the additional PLC load and bus load of acyclic communication (reading data sets).
This is no good solution for a cyclic update of values.

Hi Mr. Sirius,

That is a good point you mentioned. I was not aware that acyclic communication with 3RW4 might cause such negative consequences! Sounds like you are already aware about something like "known issues" with acyclic communication overload ....

But I have to admit that I never thought of e.g. operation hours mentioned above in kinds of "cyclic updating value" :-)

kind regards

RAKIB

What would be the solution to my problem??

 Hi Rakib,

What is exactly the problem you are now speaking about although you can find the proposed solutions (cyclic and acyclic retrieving the required information) above?

kind regards