MODBUS: Installation/Troubleshooting

1) The subject line infers that this meter-to-software Modbus communications link has not yet worked properly, that this is still the 'start-up stage, correct?

2) >Some of the information/readings displayed are wrong.
a) That means that your software package reads values, but does not read the correct values, correct?
b) What software are you using?
c) What model/brand energy meter?
d) what model/brand serial-to-ethernet converter?

3) When you say that Modscan showed the wrong register values, please provide a couple of examples of what the value should have been, and what Modscan showed as the register values.

Comments:
Typically, Modscan is used to "prove" the comm link and to establish whether the register addressing is zero based or one based, because addresses and formats are so readily changed in Modscan and the results of the change viewed instantly.

An offset of one in register addressing causes errors by getting another register's data. When reading floating point or long integers that use two register number formats, half the data is from one value and half the data from another value.

Or there can be issues with interpretation of the format by the master (software). For instance, integer data frequently needs to be scaled by a math operation (define a decimal point).

>The problem is somewhere in Modbus protocol.
>Can I re-install Modbus driver?
>How can I re-do the modbus installation from start?

Your software is not reading the correct values and you can't read the energy meter's registers with Modscan. Therefore your conclusion that the software's Modbus driver is faulty has a low probability.

The probability of 2 Modbus masters failing to read from a slave is low, especially when this type of start-up problem is not at all uncommon. The problem is most likely in the setup/configuration of both the software and/or Modscan, and/or serial server

>The problem is somewhere in Modbus protocol
Well, sort of. Modbus is never plug and play. It is configuration intensive.

>RS-485 to Ethernet converter
There are serial servers that are specifically designed for Modbus. Are you using one of those? What brand and model?
Some models come from the factory without the Modbus driver installed, and require driver installation.

You can play the re-install software game if you want, but if I were working on it, I'd be working with Modscan to read data that makes sense and is properly formatted.