Janitza UMG503 to Wonderware via MODBUS

Please help,

I try many way to define item name in Wonderware Intouch 9.0 to read data in holding register of Janitza UMG503 Power meter such as r8000, 8000 F, 8000 S, i8000. But it did not work.

I using Modicon modbus driver come with Wonderware IO Driver CD.

Please help to explain how to define item?

Thank you,
KIPeet