beautypg.com

Writing opc values, Writing opc values -2 – Rockwell Automation 1757-PROCESSLINX ProcessLinx OPC Server to Server Software User Manual User Manual

Page 46

background image

Publication 1757-UM002B-EN-P - January 2003

4-2 ProcessLinx Runtime Operation

Writing OPC Values

In runtime, values can be manually written to an OPC Item. Select and right
mouse click on the desired TagMap’s OPCItem1 column. Select Write

OPCItem1 or OPCItem2 from the corresponding pop-up menu.

Figure 4.1 Writing to an OPC item

Enter the new value in the Current Value field. Click WRITE to force an OPC
write to the specified OPC Item. To verify the value was correctly written, click
READ. WRITE is disabled if the Group data flow property for this Item is set
to “read”.

The Write Tag dialog box helps debug OPC Item problems. If the OPC Server
for this item has an available sub-status message, it displays in the Message
field.

TIP

A ‘?’ displayed for Current Value and/or Current Quality
indicates that the value for the OPC Item is suspect. This
could be the result of an invalid tag reference or a
disconnected OPC Server.