Hi Colm,
you might use the possibility to handle notifications that are triggered by the external data source for getting the desired information from the scale. This would be very similar to the usage of socket agents for EWM MFS. Functionality to read data from (data points/tags of) external data sources (like RETRIEVE queries of PCo's OPC DA agents) aren't implemented for PCo socket agents.
Handling of notifications in Business Suite systems is described here: http://scn.sap.com/docs/DOC-27547. It also will work for notifications of socket agents if you add a notification destination which is based on a destination system of type SAP NW.
Greetings
Uwe