Siwarex U loss in weight

how can gravimetric (loss in weight) be implemented, if we have two Siwarex U modules? are these modules only for weighing? or do they have the gravimetric algorithm inside them? which hardware and software are required to have the system working?

7MH4601-1BA01
SIWAREX U WEIGHING ELECTRONICS (TWO-CHANNEL VERSION) * FOR CONNNECTING TWO SCALES * FOR SIMATIC S7-300 AND ET200M * RS232 INTERFACE FOR CONNECT. OF A PC * TTY INTERFACE FOR REMOTE DISPLAY CONNECTION WITH BUS CONNECTOR

Hi
For Loss In Weight you'll need a Siwarex FTC Weighing Card 7MH4900-3AA01
Siwarex U is for Non Automatic Weighing Instruments NAWI