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There is really little to do to configure the ValuPoint to be a Modbus TCP server. The ValuPoint needs an IP address and you have already set that via the Network page. The only other thing is to verify that the Modbus Port number is set to a non-zero number. Port 502 is the port set aside for standard Modbus TCP use and should be used unless you have a specific reason not to.
If you will not be using Modbus TCP and wish to disable it, enter zero for Modbus Port, and click Set Ports. Following the next restart, you will be unable to connect via Modbus TCP with port set to zero.
IMPORTANT: The Modbus port will be initially set to zero as shipped from the factory. You will need to change it to 502 and restart before connecting via Modbus TCP for the first time.
The local registers in the ValuPoint will be most often accessed as holding registers, but can also be accessed as input registers (for reading but input registers cannot be written to). If the local register is defined as 16-bit signed or unsigned, then it can also be accessed as a coil or discrete input (for reading). When accessed as a single bit Modbus register, the value read by the Modbus master will be 0, or 1 if the local register contains 1 or any other non-zero value. Of course the remote master can only write 0 or 1 to a coil. Note also that a local register defined as something bigger than 16-bit cannot be accessed as a coil or discrete input.
The register numbers that the remote Modbus TCP client should read or write are simply those shown in the first column on the Local Registers page.
The first 24 registers are defined as floating point register pairs and assigned to the 12 physical input points. Viewing the floating point data using ModScan is illustrated below. The default data format is "Most significant register first" when selecting floating point in ModScan.
The two registers assigned to the relay outputs, registers 25 and 26, may be read and written as coils.
The ValuPoint brand new out of the box will have no registers configured other than I/O points. There will be a single holding register accessible for diagnostic purposes, at register number 8801 (or 48801 if using Modicon notation). The content of this register will be firmware revision expressed as a 3-digit number "abbcc" where "a" is the major revision, "bb" is minor revision, and "cc" is build iteration. This should correspond to the firmware revision displayed on the home page (index.html) of the web user interface for the device, which is displayed as "a.bb.c".