PM5110 reading internal registers

[kasmic_mike]

@LeTomas,@FedericoM,@Bastian_Schmitz 

Hello,

Has any one succeeded on reading  registers 3020,3000 for PM5110 with ESME Using M241 PLC MODBUS.

i configured my M241 SL2.

The data access type set to function code 03 for read only

1.The master MODBUS IO SCANNER is showing running.

2.the generic bus shows an orange triangle

When I set my data access type to function code 16 the orange triangle turn to running and bus runs  

but I still could not see any voltage values reading.

 see attachment.

thanks

[LeTomas · Accepted solution]

Hi @kasmic_mike 

I have played with one of the PM5xxx in our lab with the M262.

Please check the example project in the next link:

https://schneider-electric.box.com/s/lhuus6bvlcivkmkbxvqsn9fc26c26ffa

In the project you will see that I have used the FC03 along with some function that i have done to convert the 2 word to real.

Check if this example works on your side with the M241, then change/add another channel to access to the registers that you want and be careful with the length of the variables.

Best regards,

[kasmic_mike]

thanks i am going to check through the example critically. however if you have some examples with LD blocks or literature it will guide  me through. because am not so good with the structured programme.  

[Marian_Pavlik · Accepted solution]

Hello,

there are to tricks to reach good result.

From modbus.org > 

Registers are addressed starting at zero. Therefore register numbered 1 is addressed as 0.

To read voltage registers starting from register 3020 via M241 Modbus IO scanner you need to ask for number of register minus one to ask register address so 3019 = 16#0BCB.

The reason of your error is that Voltage value is FLOAT32 what is in 2 registers.

If Modbus request is moved by one register you ask not valid data and get Exception answer.

The second is that PM5000 and M241 use different word order in FLOAT32 so you have to swap WORDs to get correct result.

To that reason you get nice example and function FC_FLOAT32_REAL from Leandro Tomas Ahumada.

[kasmic_mike · Accepted solution]

thanks @Marian_Pavlik @LeTomas 

your guidance was really helpful.  I was able to read register for voltage, I used the excel float32 to real at above link to confirm reading.https://ckm-content.se.com/ckmContent/sfc/servlet.shepherd/document/download/0691H00000EF0hoQAD 

Am now working on the swapping WORDs. then display them on HMI

[jhonut]

Hi!
Very useful the excel. Do you have a version of it for reading some energy (4 registers) parameters?

Many thanks in advance!