# Calling a Pager

It has become fairly common to have the Catalyst call a numeric or alphanumeric pager system with an alarm call. The RTU is well equipped to handle many of the current pager protocols. An overall understanding of the sequence of events will make the required configurations proceed smoothly.

Typically, a call to the pager service number is placed. After a short period (usually 5-12 seconds), the pager system answers then gives a beep or a short burst of beeps. This is the signal to begin entering the number you want to be received and displayed by the beeper. When the information is complete, the pager terminal will hang up.

When a numeric/beeping pager is configured for alarm calls, the Catalyst will call the service number, playback the “callback” number, and hang up. By default, the “callback” number is the phone number of the Catalyst making the call. This number can be modified to suit your needs. It may be necessary to enter delays in the dialing string get the timing of the event correct. One comma in the dialing string represents a one-second delay. Enter the appropriate number of delays required to get the timing correct.

A alphanumeric pager session consists of the Catalyst dialing the pager service provider access number and delivering as many blocks as required or limited using TAP protocol transactions. It is assumed that any transaction confirmed by the TAP provider will get delivered to the terminal destination. The session result and any error diagnostics provided by the service provider will be logged.

How those messages are delivered, depends on a number of factors:

- Length of channel text messages
- Number of channels to be reported
- Pager block message size, typically 120 – 240 bytes

Service providers will not always send the messages in sequence, however each message header identifies the report block number.

Note: RACO strongly recommends that you configure other non-pager phone numbers at the appropriate place in the dialing list. This is to insure that if for some reason the pager system cannot be activated, you will still get a timely warning from your RTU.