Modbus TCP Same address, different value

Ignition
,
1

Hi!
So, I have connected ignition to a Power Meter module via Modbus TCP, however I’m having an issue when I use “Bulk” (or group) addressing.

Here, you can see that I have a group called “Corrientes” and a single tag called Ib (current phase 2):

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From the addresses, I assume that both Corriente_1 and Ib are referencing the same address (1101), however I’m getting a wrong value when referencing it within the group:

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Any Ideas why could this be happening?
This difference was noticed while using Quick Client before registering the tags. I still registered the tags to see the differences in real time.

I’m using 0 based registry (no Idea it is correct since the PM manual doesn’t say so) and Ignition 8.0.5.

Thanks in advance, guys!

2

Why do you think they are the same tag?

Corrientes0 is 2 registers, 1100 and 1101.
Corrientes1 is 2 registers, 1102 and 1103.

Ib is 2 registers, 1101 and 1102.

You’re using a 32-bit type so each tag requires 2 registers.

1 Like
3

Well, according to this manual (and the range used), I assumed it was a double Integer

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Hold on, how many bytes does a register have?:thinking:

4

Well, either way, Switching to UInt16 did the trick, now I have my proper values.

Thanks a lot Kevin!

5

Modbus registers are 16-bit (2 bytes).

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6

That’s why!

Thanks a lot!