Siemens simatic s7 200 analogue modem siemens 6es7241 1aa22 0xa0 an analogue module from the simatic s7 200 family that is designed to increase the functionality of an s7 200 plc the module is ideal for remote diagnosis and maintenance tasks and has many features that ensure top performance e g call back function password protection sms pager message dispatch led indicators for internal modem functions etc the modem is easily retrofitted as a replacement for external modems improving