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　 　 PCM30 PDH Interface Converters Power
Distribution		 SCADA_RTU
　  OMPCM30 　 　 　 　 　 　
　 　 　  Fiber Optic Multiplexer+PCM SDH Distribution
Frame		 Transmission Power Antenna
　

　

 　
    　
 An classical PCM30, multiplexex 30 channels of voice data into one 2.048Mbit/s data signal, E1 interface is used to connect with the fiber optic multiplexer, data microwave or frequency amplification. With the optical interface, the equipment can transmit 30 channels voice data to remote by directly plug the fiber. Various of interfaces, such as, remote 2/4 EM interfaces, RS232 interfaces, Carrier magnet interfaces, Ethernet interfaces, V.35 interfaces, and stereo signal interfaces.
 　
 

Summary  

   
　 　 　 　 　 　 　 　 　 　 　 　 　
　








PCM30
principle

　

　

　

PCM30
notion

 　
  • How can analog signals come to digital signals:
    Analog signals, The voltage of the analog signals ups and downs according to the times. A string of 1 and 0 constitute the digital signals. Specialized IC chip complete the analog signals to digital signals. The process which is called sampling and coding. The chips TP3067, TP3057 and TP3071 are in common used.
                   
    When give a slot pulse to TP3067, the analog comes to the digital DSTX, This code is in a time when there is a slot pulse, or else it is resistance.
  • How 30 channels voice signals come to 1 channel digital signal
    Each channel has a different slot pulse. These time slot are put in order and never overlap.
                
    Because adopting different time slot to 30 channels, so the 30 channels of digital signal won't overlapf. Collecting 30 channels of voice signal together to make up the BUS. The process is called multiplexing. 
                 
  • Frame structure and 2M interface
    The above table is combining 30 channels of digital signal into one channel, which is called the DSTX, and With a period of 125us. We divide the period into 32 parts, named time slot0, time slot 1, till the last time slot 31.
    Each time slot has 8 codes, there are totally 256 codes, each code named 1 bit, so 1 bit is 0.488us. According to the fomula f=1/T, the rate of the data is 2048K.
 　
　 　 　 　 　 　 　 　 　 　 　 　 　
　 Features

 
 OMPCM30 is 19 inches wide, 1U high, all of the unit cards are supported hot swapped. 
           

           

  •  With a turnover front panel, All the channel cards can be hot-swapped after turn  down the panel.
  •  Each unit card has fault discriminant circuit, once there is a failure, the indicators on the front panel will be power off.
  •  Double power module AC220V and DC48V can work simultaneously.
  •  With optical interface.
  •  Total aluminum structure.
 　
　 　 　 　 　 　 　 　 　 　 　 　 　
　







 Application 1

  

　
The PABX gives the number to the remote, widely used in power, Public Security, Armed Police, Petrochemical and Oilfield.



 The advantage of this program is to save a pair of the fiber optic multiplexer, but the defect is it can only transmit 30 channels of voice. If more channels need, we must use the fiber optic multiplexer.
 		　
　 　 　 　
  Application 2   　
                        
Our PCM30 can connect the fiber optic multiplexer or the microwave equipment of any manufacturers.
　 　 　 　
  Application 3   　

  
  To use the analog line 2 to connect the PABX/PBX and the OMPCM30.
  Using the PABX and 2M interface board to connect with the OMPCM30, this method not only saving the investment of the PABX, but also saving a PCM30. What's more, it can save many distribution wire and project maintenance.Not all of the PCM30 can accomplish the plan, because there is some difference between the TS16 slot of the PABX and the PCM30. Signaling programming of the OMPCM30 is a condition to implement the program. 
　





　
　

How to use？  

　
 15 RJ45 connectors from J1 to J15 which conrrespond with the analog interface of the 15 unit cards inside. EM connectors to transmit EM signals, NM is network interface.
 A pair of coaxial is E1 interface(2M), the optical interface is below, the optical interface and the E1 interface is one of the two elected relations.
AC220V and DC-48V can work simultaneously or respectivly to make a protection for each other.
 　
　 　


          OMPCM30 technique parameters
     If you need user's manual, please telephone us.