Nortel Networks M3110 - Manual (Page 488)

Page 488 of 504 Appendix E: M3110, M3310, and M3820 telephones
553-3001-367 Standard 3.00 August 2005
Alerting tone characteristics
The tone frequency combinations are as follows:
A 500 Hz buzz signal is provided for incoming call notification while the
receiver is off-hook.
Power requirements
The Meridian digital telephones are loop powered. Loop power, originating
in the ISDLC or the DLC, consists of a 30 V DC power source and assumes
a 3500 ft. (1219 m) maximum loop length of 24 AWG (0.5 mm) wire and a
minimum 15.5 V DC at the telephone terminals.
Note: The loop length limit is defined by a 15.5 dB loss at 256 KHz.
Longer lengths can be determined using the wire’s gauge and insulation.
Some configurations of telephones and options need more than basic loop
power to operate. Table 82 lists the types of Meridian digital telephones and
shows when additional power is needed to operate the telephone or its
optional hardware. Power Supply Boards come installed in
factory-assembled configurations that require additional power.
Tone Frequencies Warble Rate (Hz)
1 667 Hz, 500 Hz 5.2
2 667 Hz, 500 Hz 2.6
:
3 1600 Hz, 2000 Hz 5.2
4 1600 Hz, 2000 Hz 2.6
:
3 333 Hz, 250 Hz 5.2
4 333 Hz, 250 Hz 2.6