This standard specifies the uniform requirements of inspection method for networking of subscriber exchange and on-line quality tracing.
This standard is applicable to digital programmable subscriber exchange and analog programmable subscriber exchange.
2 Reference Standard
GB 3971.2 Interoffice Junction Digital Line Signaling System for Telephone Automatic Switching Network
GB 3377 Multi Frequency Register Signaling System for Telephone Automatic Switching Network
GB 3378 Subscriber Line Signaling System for Telephone Automatic Switching Network
GB 3379 Interoffice Direct Signaling System for Telephone Automatic Switching Network
GB 7611 Parameters of Digital Interface for PCM Systems over Telecommunication Network
GB 6879 Technical Requirements of the 30 Channels Pulse Code Modulation Multiplex Equipment at 2048 kbit/s
GF 002 General Technical Specification for Telephone Switching Equipment of Ministry of Posts and Telecommunications
YD 344 Requirements for PABXs Access to Public Telephone Switching Network
3 Conditions of Public Test
3.1 Testing interface shall be subject to the interface terminal of distribution frame exchange and various operation system errors shall be deducted.
3.2 Before testing, public ground wire shall be prepared and power supply "+" shall be connected to the ground.
3.3 Reference frequency for reference: digital exchange 1020Hz; analog exchange 800Hz.
Reference level for reference: digital exchange -10dBm0; analog exchange 0dBm.
3.4 All tests shall be conducted under the required conditions of impedance matching.
3.5 25~35mA of operating current is generally selected for testing.
3.6 Each parameter of transmission indexes is tested for four times, the worst value will be taken as the result and the unqualified indexes (if any) shall be doubly tested.
3.7 Testing shall be conducted under normal operation environment.
3.8 The adopted instruments and equipment shall be within the validity of metering qualified.
