Dear All,

I am communicating Conserve energy meter EM 6433H with S7 1200 PLC CPU 1214 DC/DC/Relay with the help of CB 1241. We established Modbus RTU communication with EM 6433H. And the Values are also being received. But the values are coming in exponential format.  Pic is attached for your reference. 

Example: Energy meter is showing 32.23 Watts, but we are getting is -8.35888E+24

We are not able to use the these values in our further process. 

Please suggest us how to convert these into a simple 32 bit real data, just like 32.23.

Thanks in advance for your kind co-operation.

Regards,

Eswar.Marasu,

Hello Eswar;

Konstantin is right, this look like a Little Endian/Big Endian problem.

https://en.m.wikipedia.org/wiki/Endianness

The solution is to manipulate (swap) the byte order of the data you are transmitting 

https://support.industry.siemens.com/tf//us/en/posts/converting-big-endian-to-little-endian-in-tia-portal-for-s7-1200/200100/?page=0&pageSize=10

Hope this helps,

Daniel Chartier 

Dear Daniel Chartier,

Thanks for your valuable reply. Could you please suggest  any Instruction/Library for converting Big Endian to Small Endian in  S71200 PLC program. 

Thanks in advance for your kind co-operation.

Regards,

Eswar.Marasu

Hello Eswar;

What do you think of the contents of the  second link provided in my earlier reply?

SWAP is a Step 7 (TIA Portal) instruction, not a library, but it should help you fix the big endian problem.

Hope this helps,

Daniel Chartier 

Dear Daniel Chartier,

For my application, it has been used "ROR" (Rotate Right) after converting big Endian to double word.

This double word is again converted to real. Now its working perfectly. 

Thanks for you peoples valuable  support.

Regards,

Eswar.Marasu.