Datasheet

Modbus TCP Communication HIMA H41q/H51q ↔

↔↔

↔ Emerson DeltaV

The configuration of the VIM is carried out with

Mynah’s “VIMNet Explorer” which is not necessary for

operation of the VIMs and can therefore be installed on

separate computer which needn’t be permanently

connected to the communication network. When the

VIM needs to be configured initially or for expansion of

available Modbus TCP devices the VIMNet Explorer

must be connected via a Network Interface Card (NIC)

which must reside in the same network range like the

VIM itself. I.e. VIM host address 192.168.0.241 is only

accessible from 192.168.0.x when the NICs netmask is

255.255.255.0. Keep this fact in mind when you

encounter connection problems between VIMNet

Explorer and the VIM.

When the VIMNet Explorer is initially started the tree

consists just of the area “VIMNET” and the underlying

“I/O Net” similar to the DeltaV Explorer’s view. The

initial configuration of the VIM to be ready for Modbus

TCP communication requires the following seven

steps:

Figure 2.4: VIMNet Explorer Tree

1. Add a controller to which the VIM should be assigned using the context menu of I/O Net. Use the

same name like in DeltaV Explorer to simplify identification of corresponding structures.

2. Add a VIM below the newly created controller using the controller’s context menu.

3. Configure the VIM’s properties according to Figure 2.5 to be of type “I/O VIM – Modbus TCP”,

select redundancy if necessary. Enter the appropriate IP addresses and subnet masks.

Figure 2.5: VIM Properties

4. Add a new Modbus device below the desired serial card. The device must be defined in VIMNet

Explorer and DeltaV Explorer whereas the communication data (datasets) are only defined in the

DeltaV Explorer.

5. Configure the device properties according to Figure 2.6 with Device Address and primary and

secondary IP address of the H41q/H51q. The used Port should be set to 502 and the Number of

Simultaneous Messages must be set to 1. For a simplex connection you need to set to “Simplex

Device” and use just one IP address. A redundant connection can be set to “Redundancy with

Switching IP” (which means the active VIM stays active when a connection failure to it’s active

slave occurs and it just uses the secondary IP address via the cross link cable) or to “Redundancy

with No Switching IP” (which in turn means the master also switches when a connection failure to

it’s active slave occurs; this is the normal behaviour of the DeltaV redundant serial card).