General
1-1
1558A APS
General
1.0
Introduction
The TxPORT 1558A APS (Automatic Protection Switch)
unit provides automatic T1 service restoration from a
degraded or failed T1 facility to a standby T1 facility. See
the ‘Operation’ chapter for a typical APS application.
Switching from the failed line (Path A or Path B) to the
standby (Path A or Path B) is based upon user definable
switching alarm thresholds (errored seconds, consecutively
severely errored seconds, loss of signal, loss of frame). The
1558A APS is fully compatible with all industry standard
APS equipment that complies with PUB 54017, 1991.
1.1
Design Highlights
The APS unit is designed so that it can be configured to sup-
port a wide variety of user applications. The key features
and functions are:
• Mission-Critical Automatic Protection Switching from a
Fail or Impaired T1 Facility to a Standby T1 Facility
• D4 or ESF Framing,
• AMI or B8ZS Line Coding
• Integral ESF CSUs (TR 54016 compliant)
• 24 Hour Performance History
• Revertive and Non-revertive Operation
• User-Definable Alarm Switching Thresholds
• Proactive Call-on-Alarm Reporting (requires manager)
• Desk Top or Rack Mount
• Redundant Power Configurations (AC or DC)
• Bantam Test Access Jacks
• Complies with AT&T 54017 Automatic Protection
Switching, 1991
• FCC, DOC, UL, and CSA Compliant
1.2
Specifications
T1 Network Interface
Line Rate:
1.544 Mbps
Framing:
ESF
Line Code:
AMI or B8ZS
DS1 Interface:
+1 to -27 dB ALBO, 100
Ω
(
±
5%)
Connector:
RJ 48 jack
Overvoltage
Primary and Secondary lightning
Protection:
fusing for line cross
ESF Mode:
Pass/Block Facility Data Link
to/from Network
CPE (Equipment Interface)
Line Rate:
1.544 Mbps
Framing:
D4 or ESF
Line Code:
AMI or B8ZS
DSX Interface:
DSX -1 to -6 dB (ALBO), RJ 48
jack, 100
Ω
(
±
5%), 0 to 655 ft.
Connector:
RJ 48 jack
A
SUPV
PWR
B
STATUS
A
BYPASS
LOCKED
B
A
B
ALM
LOS
LP
A
SELECT
AUTO
PATH
B
STATUS
PATH
RX BRDG
TX BRDG
N
E
T
A
RX BRDG
TX BRDG
N
E
T
B
DTE
LOS
RX BRDG
TX BRDG
D
T
E
TxPORT
LP
1558A Automatic Protection Switch for customer premise
1558A
