HDSL2 TROUBLESHOOTING GUIDE
PRICING AND AVAILABILITY 800.827.0807 TECH SUPPORT 800.726.8663 RETURN FOR REPAIR 256.963.8722 www.adtran.com
INDICATIONS AND PROBABLE CAUSES
Front Panel or Circuit Parameters Indicate Abnormal Operation
Connect a terminal or PC to the
■Is signal quality fluctuating (this would occur when
■Is ATTEN (pulse attenuation) > 30 dB?
■Are there any errors counting on the ES, SES, or UAS registers?
If the above conditions do not exist, the circuit should provide quality service; however, if any of the above conditions exist, a cable problem or excessive loss situation is probable and more detailed cable testing should be done to verify all HDSL2 Loop Specifications are met. These conditions may also reflect intermittent cable faults or excessive noise impairments. If intermittent faults or noise impairments are suspected, select “5” from the HDSL2 Main Menu and review the Performance History Screen.
Front Panel Indications Under Normal Operation
STATUS | ● Green |
Circuit Parameters Under Normal Operation
■LOSS < 30 dB
■Good signal quality with no fluctuation
■All HDSL2 Deployment Guidelines are met
HDSL2 DEPLOYMENT GUIDELINES
■Cable pairs must be
■Total bridged tap < 2.5 kft
■No single bridged tap >2 kft
■196 kHz insertion loss ≤ 35 dB
■Pulse attenuation (loss on HDSL2 Span Status Screen) ≤ 30 dB
■Maximum loop resistance is 900 Ω
■Impulse noises < 50 dBrn as measured using a 50 kb filter
■Wideband noise ≤ 31 dBrn as measured using a 50 kb filter
For further information regarding deployment guidelines and applications, reference ADTRAN’s Supplemental Deployment Information for HDSL/HDSL2 document, P/N
HDSL2 Loopback Control Codes
Name | Code | Comments |
Arming | 11000 | Signal sent |
Arming (ESF) | 0001 0010 1111 1111 | state make transition to armed state. Detection of either code results in |
| (12 FF Hex) | Smartjack loop up, if NIU loopback is enabled. |
Activation | 1101 0011 1101 0011 | Signal sent |
(D3D3 Hex) | loop up state. Loop up state timeout is programmable from the | |
Activation | 1100 0111 0100 0010 |
|
(C742 Hex) |
| |
Deactivation | 1001 0011 1001 0011 | Signal sent |
| (9393 Hex) | armed state. |
|
|
|
Disarming | 11100 | Signal sent |
Disarming (ESF) | 0010 0100 1111 1111 | make transition to disarmed state. |
| (24FF Hex) |
|
Arming Timeout | N/A | 2 Hours |
|
|
|
N/A | HDSL2 element in loop up makes transition to armed state. | |
|
| Programmable from |
Loopback Timeout | 1101 0101 1101 0110 | Signal sent |
Override | (D5D6 Hex) | return to previous value when pattern is removed. Arming pattern |
|
| (11000) must precede this pattern. |
Span Power | 0110 0111 0110 0111 | Signal sent |
Disable | (6767 Hex) | will return when pattern is removed. Arming pattern (11000) must |
|
| precede this pattern. |