Overview The DSX-3 is a common point in central offices or network nodes that provides the following functions: • Termination of a variety of equipment referred to as network elements (NE). The NE are permanently cabled to this common point during the initial installation and remain terminated at the DSX-3 for the life of the equipment. • Cross-connection of two NE together to configure a circuit. The cross-connect jumper is a semi-permanent connection that may be changed as the telephone network evolves and circuits are re-configured to meet service demands. As new equipment is introduced into the network, this replaceable jumper facilitates a means to re-connect equipment together throughout the continuous upgrade of equipment. • Access of circuits by means of jacks. Jack access provides a means to: - Test circuits when a failure occurs and sectionalize portions of the circuit to determine which NE is defective. - Patch around the failed NE to quickly restore service until the defective NE is repaired. - Patch existing NE to new NE during cutovers when portions of the network are upgraded to a new technology of equipment. After the patch is made, the old jumper is removed and a new jumper is added to connect old and new NE together and then the patch is removed.It is important to understand that based on the application, the appropriate module must be utilized to ensure proper signal monitoring. The following diagram illustrates the difference between each module. To accomplish the flexibility of this system, an equal level point (ELP) must be established at the DSX-3. The ELP ensures that signals from all NE are at the same amplitude and signal strength at this common cross-connect and access point; the DSX-3. When a common ELP is established, any two NE may be connected together without re-adjusting the signal strength. Furthermore, when circuits are re-configured during the evolution of the network, re-adjustment of NE is not required. DSX-3 Cable and Cross-Connect Limits application note 2 www.adc.com • +1-952-938-8080 • 1-800-366-3891 3/01 • 1228 DSX-3 Cable and Cross-Connect Limits Original Specs CB119, Bell Laboratory compatibility bulletin, defined the standard ELP pulse template. An end to end maximum budget loss of 12.15 dB.between any two NE consisted of: 5.5 dB (450' of “728A” type equipment cable) between the NE and DSX-3 and 1.15 dB (27' of “RG59” type cross-connect jumper) between DSX-3 terminations as shown in Figure 1. DSX 728A 450' 5.5 dB DSX 728A 450' 5.5 dB RG59 27' 1.15 dB NETWORK ELEMENT NETWORK ELEMENT Figure 1 CB119 Cable and Cross-Connect Limits As networks evolved, and the high bandwidth demand of DS3 service expanded, DSX-3 systems have often grown beyond the physical limitations set forth by the 728A cable and RG59 cross-connect. The physical diameter of the cable congested cable and cross-connect routes within the central office. Also, DSX-3 system capacity is limited by the allowable cross-connect jumper length and the maximum number of modules placed within that maximum length. 734A type cable, with a smaller diameter and equal electrical characteristics, soon became the equipment cable standard. This cable still caused cable congestion in the central office as demand for DS3 service exploded. Newer Cables The use of 735A type cable and cross-connect jumpers, dramatically reduces cable congestion, but also reduces the length of transmission. A study of central offices determined that 90% of NE can be cabled to the DSX-3 within the limitation of 735A cable at 225'. 735A cable and cross-connect limits are shown in Figure 2. DSX 735A 225' 5.5 dB DSX 735A 225' 5.5 dB 735A 20' 1.15 dB NETWORK ELEMENT NETWORK ELEMENT Figure 2 735A Cable and Cross-Connect Limits 3 www.adc.com • +1-952-938-8080 • 1-800-366-3891 3/01 • 1228 DSX-3 Cable and Cross-Connect Limits Proposed Limits The 20' limitation of 735A cross-connect jumpers restricts the system capacity of the DSX-3. The high growth rate of DS3 service has prompted ADC to expand the DSX-3 capacity by engineering high density DSX-3 modules and extending the cross-connect limits. The proposed cable and cross-connect limits to expand DSX-3 capacity are shown in Figure 3. DSX 735A 200' 5.0 dB DSX 735A 200' 5.0 dB 735A 60' 2.15 dB NETWORK ELEMENT NETWORK ELEMENT Figure 3 Proposed 735A Cable and Cross-Connect Limits In addition to extending cross-connect limits, ADC’s Mini-DSX-3 provides the highest capacity DSX-3 solution. The high density design of Mini-DSX-3 can double or triple system capacity when compared to traditional 24 or 16 termination chassis as shown in Figure 4. The modular Mini-DSX-3 terminates 48 DS3 network elements in a single 23" chassis. Figure 4 DSX-3 Maximum System Capacity Based on Single Line-Up with Ten Chassis Per Bay Terminations per Chassis 16 24 48 60' Cross-Connect 17 Bays 2720 4080 8160 20' Cross-connect 4 bays 640 960 1920 Cross-Connect Design Length The maximum cross-connect length within a given DSX-3 system must reach from the top of the first bay to the bottom of the last bay of a line-up to ensure that any two NE may be cross-connected together as shown in Figure 5. ADC Telecommunications, Inc., P.O. Box 1101, Minneapolis, Minnesota USA 55440-1101 Specifications published here are current as of the date of publication of this document. Because we are continuously improving our products, ADC reserves the right to change specifications without prior notice. At any time, you may verify product specifications by contacting our headquarters office in Minneapolis. ADC Telecommunications, Inc. views its patent portfolio as an important corporate asset and vigorously enforces its patents. Products or features contained herein may be covered by one or more U.S. or foreign patents. An Equal Opportunity Employer 1228 3/01 Revision © 1998, 2001 ADC Telecommunications, Inc. All Rights Reserved Web Site: www.adc.com From North America, Call Toll Free: 1-800-366-3891, Ext. 63475 • Outside of North America: +1-952-938-8080 Fax: +1-952-946-3292 For a complete listing of ADC's global sales office locations, please refer to our web site. CHASSIS 9 CHASSIS 8 CHASSIS 7 CHASSIS 2 CHASSIS 1 CHASSIS 4 CHASSIS 3 CHASSIS 6 CHASSIS 5 CHASSIS 9 CHASSIS 8 CHASSIS 7 CHASSIS 2 CHASSIS 1 CHASSIS 4 CHASSIS 3 CHASSIS 6 CHASSIS 5 CHASSIS 9 CHASSIS 8 CHASSIS 7 CHASSIS 2 CHASSIS 1 CHASSIS 4 CHASSIS 3 CHASSIS 6 CHASSIS 5 CHASSIS 9 CHASSIS 8 CHASSIS 7 CHASSIS 2 CHASSIS 1 CHASSIS 4 CHASSIS 3 CHASSIS 6 CHASSIS 5 26"5" 26"10" 26" 26"10"10" 5" CABLE TROUGH CABLE TROUGH CABLE TROUGH CABLE TROUGH CABLE TROUGHCABLE TROUGH CHASSIS 10 FUSE PANEL CHASSIS 10 FUSE PANEL CHASSIS 10 CHASSIS 10 CABLE TROUGH CABLE TROUGH FUSE PANEL FUSE PANEL Figure 5 Typical System Cross-Connect Design Length . required. DSX-3 Cable and Cross-Connect Limits application note 2 www.adc.com • +1-952-938-8080 • 1-800-366-3891 3/01 • 1228 DSX-3 Cable and Cross-Connect Limits Original. 2 735A Cable and Cross-Connect Limits 3 www.adc.com • +1-952-938-8080 • 1-800-366-3891 3/01 • 1228 DSX-3 Cable and Cross-Connect Limits Proposed Limits The