Error when reading from RVG200 recorder via Modbus/TCP
Hello,
we are trying to read analogue sensor values from an RVG200 recorder but fail to get values. The recorder is configured to work as slave. We are able to connect to the recorder but when we try to read holding registers (function code 3) 1 and 2 for sensor A1, we get an error code 4. We then stumbled across the sentence "Read holding registers – reads 8 consecutive analog values, starting from a specified address. The
recorder returns zeros for registers that do not contain defined data" in the manual but could not figure out the meaning. Does that mean that we always have to read 8 values (i.e. 16 registers) at a time? If we try to do that, we get error code 2. Or does it mean, that we will receive 8 consecutive values in time for one sensor?
For our tests, we used the Python Library pyModbusTcp, which works well for other ABB measuring equipment.
Thank you in advance for your support!
we are trying to read analogue sensor values from an RVG200 recorder but fail to get values. The recorder is configured to work as slave. We are able to connect to the recorder but when we try to read holding registers (function code 3) 1 and 2 for sensor A1, we get an error code 4. We then stumbled across the sentence "Read holding registers – reads 8 consecutive analog values, starting from a specified address. The
recorder returns zeros for registers that do not contain defined data" in the manual but could not figure out the meaning. Does that mean that we always have to read 8 values (i.e. 16 registers) at a time? If we try to do that, we get error code 2. Or does it mean, that we will receive 8 consecutive values in time for one sensor?
For our tests, we used the Python Library pyModbusTcp, which works well for other ABB measuring equipment.
Thank you in advance for your support!
Answers
Greetings,
If I am not wrong, you are trying to read Real Data Type Value.
Did you try to read Word Data Type, instead of Real Data Type?
Maybe you need to use Words_To_Real or something similar, to get Real Data Type Value.
Hope it helps you.
If I am not wrong, you are trying to read Real Data Type Value.
Did you try to read Word Data Type, instead of Real Data Type?
Maybe you need to use Words_To_Real or something similar, to get Real Data Type Value.
Hope it helps you.
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