Hi
You will need to configure the scanners to point to your SAP servers IP address (your hardware supplier will be able to help with this) and ensure that your custom txns have been 'published' for ITS - Your developer should know how to do this.
As with any printer, you will have to set it up on SAP first. This is usually done by the BASIS team. Once the printer is then 'live' on SAP you will need to make the required config settings via OMLV.
Hope this helps
Cheers