Dear Shruti,
it is possible that most of these printers are so-called "host-based" printers.
For example, I could not find the specification of P1020, but 1020 is a host-based printer.
In this case, SAP Note #1617166 - "Host-based Printers from SAP" describes that only SAPWIN-device types can be used with Access Method G (frontend) or Access Method S (remote printing with SAPSPrint).
Check the manuals of your printers for exact specifications.
Best regards,
Laszlo