FXS Line Testing

You can test FXS telephone lines that are connected to the device's FXS ports. The test is done per FXS port and FXS country coefficient type - USA (70) or TBR21 (66). The results of the test are sent to syslog and includes various line statuses and electrical line measurements, for example:

■ Hazardous Potential Tests (HPT) - hazardous AC or DC voltage is present on the tip and ring or both.
■ Foreign Electromotive Force Tests (FEMT) - foreign voltage is present on the tip, ring or both
■ Resistive Fault Tests (RFT) - tip or ring is shorted to ground, or they are shorted to each other
■ Receiver Off-hook Tests (ROH) - one or more phones are off hook on phone line during test.
■ Ringer Impedance Tests (RIT)
■ AC/DC line voltage
■ AC/DC line current
■ Line resistance
■ Line capacity
■ Hook status (on or off)
■ Message Waiting Indication (MWI) status (on or off)
■ Ring status (on or off)
■ Reversal polarity status (on or off)
■ You can only test one FXS port at a time.
■ Don’t start a new test if one is still running.
■ Each new test overwrites the previous test results.
■ The FXS port interface is out of service (OOS) during the test.
■ Make sure that a telephone is connected to the FXS port that you want to test and that the telephone is in on-hook state and not servicing any calls.
➢ To run the FXS line test:
1. Access the VoIP command set:
# configure voip
2. Access the FXS interface command set:
(config-voip)# interface fxs-fxo
3. Type the following command:
(fxs-fxo)# fxs-line-testing < Module/Port > {66|70}

For example, to test FXS port 4 on FXS module1 with coefficient type USA:

(fxs-fxo)# fxs-line-testing 1/4 70

Line Testing on FXS Port 4 in Module 1 is Executing... Please wait a few seconds.