CANOGA PERKINS 2345 T3 Fiber Optic Modem - Manual (Page 34)

EdgeAccess Universal Chassis System
Model 2345 User Manual 4-4
Set the Electrical Line Relay
Use the Electrical Line Relay option to open or close the relays for the or the inactive circuits in order
to diagnose a fault on a circuit that could not, otherwise, transmit and receive data. To set the
electrical line relay, follow these steps:
1. From the Main Menu, type 2, "Diagnostics," and press <Enter>.
2. At the Diagnostics screen, type 3 , "Electrical Line Relay" and press <Enter>, then press <Space>
to cycle between Enable and Disable.
3. To return to the Main Menu, press <Esc>.
Run Loopback
Use loopback to diagnose a fault on the optical link, either on a modem or with a cable. Set loopback
either in software for a managed 2345 or at the loopback function switch on a 2345 in a standalone
enclosure. Figures 5 through 10 show how all combinations of loopback options return the signal(s)
to the source in order to test specific parts of the circuit.
• Local loopback returns the received electrical signal to the local site and ignores the received
optical signal; turn on Local Loopback at the local modem. The remote modem returns All Ones
to the remote site. Faulty data can indicate that the local 2345 is faulty.
• Remote loopback returns the received optical signal to the remote modem and ignores the
received electrical signal; turn on Remote Loopback at the local modem. The remote modem
returns All Ones (AIS) to the remote site. Faulty data can indicate that either the fiber optic cable
link or the remote 2345 is faulty.
• Bi-directional loopback returns the received electrical signal to its local site and the received
optical signal to the modem that sent it; turn on Local loopback at one modem and Remote
Loopback at the other modem. Faulty data can isolate the faulty equipment to indicate that either
the fiber optic link or a 2345 is faulty.
To set up the software and start or stop loopback, follow these steps:
1. From the Main Menu, type 2, "Diagnostics," and press <Enter>. The Diagnostics screen appears.
2. Set Loopback Control Mode to software, if needed. Type 2 and press <Enter>, then press
<Space> to cycle between Hardware and Software, and press <Enter> to select software. To
move to the next column for a secondary or remote modem, press <Tab>.
3. To set and start Loopback, type 1 and press <Enter>, then press <Space> to cycle through the
options. To move to the next column for a secondary or remote modem, press <Tab>. When you
finish making selections, press <Enter>; loopback starts.
4. To stop Loopback, type 1 and press <Enter>, then press <Space> to cycle to Clear All. To move
to the next column for a secondary or remote modem, press <Tab>. When you finish making
selections, press <Enter>; loopback starts.
5. To return to the Main Menu, press <Esc>.