Siemens 8 system digital distribution frame
Withstand voltage: 1000V, DC for two minutes; (5) Contact resistance: inner conductor, outer conductor (specific value shall be proposed by the Supplier); (6) Impedance: 75 Ω to ground imbalance and 120 Ω to ground balance; (7) Reflection attenuation ≥ 40dB; (8) Signal rate: coaxial connector ≤ 600Mbit/s, balanced connector ≤ 2Mbit/s; (9) Good grounding; (10) 120n terminal unit shall have lightning protection function; (11) The wiring is reasonable and beautiful. [2] In fact, DDF is a kind of circuit dispatching equipment, which plays the following roles: providing direct or cross distribution connection for digital communication equipment in the machine room or some columns through various corresponding plug ropes (such as shaft cable plug rope and two core plug rope) or four core short circuit plugs, so as to achieve fixed or temporary circuit dispatching, so as to prepare a flexible dispatching circuit communication network; At the same time, it also provides a very convenient test connection point for engineering and maintenance work.
It makes it easy to detect or schedule the transmission equipment and lines. For example, if you want to adjust some systems for circuit scheduling, you only need to cross connect the DDF with a plug rope of corresponding length; To carry out the self loop test, simply connect the receiving and sending ends on the DDF with the self loop plug rope. Another function of DDF can be used as the interface of digital segment or digital link; Usually, digital segments or digital links are always terminated on the DDF. The interface between the digital transmission trunk network and the program-controlled switch can be determined by the DDF, that is, the terminal block installed on the DDF exchange side between the 2Mbit/s interface and the trunk module of the program-controlled switch. In this way, the maintenance interface between digital trunk transmission and SPC exchange is determined by DDF. The maintenance of digital transmission trunk network should include all digital transmission equipment from one end interface to the opposite end interface, such as digital transmission optical, electrical terminal, optical cable, PCM special cable, cable PCM equipment, transmission monitoring equipment, etc.
Digital distribution frame, also known as high-frequency distribution frame, has more and more advantages in digital communication. It can make the connection of digital code stream of digital communication equipment become a whole, and the input and output of signals from 2Mb/s to 155Mb/s can be terminated on the DDF frame, which brings great flexibility and convenience for wiring, wire adjustment, switching, and capacity expansion. Digital distribution frame, also known as high-frequency distribution frame, has more and more advantages in digital communication. It can make the connection of digital code stream of digital communication equipment become a whole, and the input and output of signals from 2Mb/s to 155Mb/s can be terminated on the DDF frame, which brings great flexibility and convenience for wiring, wire adjustment, switching, and capacity expansion. 20 system DDF digital distribution frame, also known as high-frequency distribution frame, has more and more advantages in digital communication. It can make the connection of digital code stream of digital communication equipment become a whole, and the input and output of signals from 2Mb/s to 155Mb/s can be terminated on the DDF frame.
