ThermoWorks RTR-500GSM WIRELESS LAN OR GSM (CELLULAR) LOGGERS - Manual (Page 3)

Initial Settings Wizard
The Initial Settings Wizard allows you to quickly enter the basic information
needed to connect through the cellular system for which you have opened an
account.
I) Setting the APN
The APN (Access Point Name) tells the system which server to use for sending
data and SMS messages to and from the RTR-500GSM. This should be set to
“wap.cingular” for AT&T accounts or epc.tmobile.com for T-Mobile.
II) User ID and Password
Unless instructed otherwise when you obtain your account, this should be left
blank. The wap.cingular access point does not require User IDs or Passwords.
III) Test the Network Connection
When you click on the Next button you will be offered the opportunity to send
a test SMS message. This should be done, as it tests the unit’s basic
connection to the network. Just enter the phone number of an SMS capable
cell phone and click the Send button. If the test message does not arrive in
short order there is a fundamental problem with the unit’s network connection
which needs to be troubleshot before proceeding to the Main Settings Window.
(Note: A successful SMS test will verify your basic account and connection
with the carrier, but it does not confirm the data account. This is done with
the Transmission Tests described in Section 11.