4 Communication
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Alpha Technologies
4.7 Installing and Using the External Modem
Uses of the External Modem
Where a network is not available, you can connect an external modem to the CFR’s RS–232
port.
The modem lets you:
• Program the CFR to send an alarm message to a remote host via the telephone line
when a power event takes place.
• Dial up the CFR for remote monitoring or control. Once connected, all RS–232 menus are
accessible.
Equipment and Settings
Equipment:
•
An external modem (US Robotics Sportster (1200, 9600, 19.2K or 28.8K baud) or
other “Hayes Compatible” modem).
•
A standard null modem cable, DB–9 male to DB–25 male.
•
Phone line access.
•
One-time access to the CFR via a computer link.
Settings:
•
RS–232 Speed: 1200 Baud between CFR and modem.
•
RS–232 Signals: Rx, Tx and Gnd.
•
Handshaking: None, neither hardware (RTS/CTS) nor software (XON/XOFF) are
used.
•
Modem Speed: Same as the modem’s.
