Modscan program can read but RTU cant

I am trying to integrate Power Logic PM750MG with my RTU. My RTU cannot read the C phase-neutral or C-A phase to phase voltage. If I use modscan program I can read all the values without any issues. Can anyone assist me. Thank you.

Are you saying these are the only values which your RTU can't read? Does it read for the other phases? Does it receive a specific error code?

Can your RTU read any value or values correctly from the Power Logic?

If so, is the format different for those values it can read versus those the RTU can't read correctly?

What is the RTU you have? Remember the data you are polling is in a floating point format
(two 16 bit integers). Are you polling enough registers to get the whole floating point value.

Here is the manual.

http://www.google.com/url?sa=t&rct=...8cw4zsDyHbssm4dlgdxpA&bvm=bv.1355534169,d.cGE

Hi I can read all other phases. Having issues with C phase and C-A. Same for both integer and floating value. For example when the PT value is full scale for all three phase. Modbus value for Phase A and B is full scale, 0 for C phase. Phase to Phase value is full scale for AB and BC, half for CA. LCD display full scale for all phase.

>Phase to Phase value is full scale for AB and BC, half for CA. LCD display full scale for all phase.

Apparently you can read values from the Power Logic into the RTU, but you do not believe the values are correct. Hence it is not a comm hardware layer issue.

Whose LCD display? The drive or the RTU? Is this the source of the discrepancy?

>If I use modscan program I can read all the values without any issues.

If Modscan can read the correct values (how do you know they're correct values?) from any or all registers in the Power Logic, then as a Modbus slave, the Power Logic is not the problem. The hardware transfers the contents of the registers.

Some issue in the RTU . . . . display not reading the register that you think it's reading???