|
Products -
MLC
|
|
Page 1 of 4 HS-20
The HS-20 system connects trunk lines with customers via a crosspoint switch matrix on the EU and the RU. One of the five trunks is responsible for data communication between EU and RU, and provides DC power from EU to RU. If a fault occurs on the power feed/data trunk, the next trunk becomes power feed/data trunk automatically to keep the system working. The rest of the trunks are available to connect the customers of RU to customer interface of EU.
The EU and OMI get their power and communicate through the backplane that is fixed on the Subrack. The OMI is used for setting up system parameters，traffic Statistics, testing operational status and displaying system information.
One connector of the EU is connected with Exchange terminals, while the other connects with the trunks of the system via the backplane. It connects customers with corresponding trunks according to demand when customer calls are setup.
The RU is fixed and sealed in a plastic housing. It can be conveniently located, such as: hanging on a pole or the wall, or fixed below the ground.
Specifications
| Operating Environment ： |
|
EU:
|
Temperature Range: +5 ° C ～ +50 ° C |
| |
Relative Humidity: 20% ～95% (No condensing) |
|
RU:
|
Temperature Range: -40 ° C ～ +55 ° C |
|
| Operating Power： |
|
EU:
|
－ 42VDC～－65VDC supply by the Exchange |
|
RU:
|
± 75VDC; supply by the EU. |
|
CUSTOMER TERMINAL:
|
-48VDC supply by the RU |
|
OMI:
|
supply by the EU. |
|
| Dimensions： |
|
Subrack:
|
19-inch rack, 355mm (8U) height, 255mm depth |
|
RU:
|
357×215×105mm |
|
| Customers： |
| |
Every unit can access up to 20 customers. |
| |
Every Subrack can hold up to 10 Exchange units. |
|
| Trunks: |
| |
Three to five pairs could be fixed in every unit as trunks |
| |
The first trunk is for power feed/data, the rest for voice |
|
| Maximum Transmission Range： |
|
EU to RU:
|
Loop resistance of 1800 Ω (the actual range achievable depends on the switching) |
|
EU to Customer ：
|
the normal range of the exchange equipment |
|
| Customer and Trunk Interface: |
|
|
Two lines; A leg and B leg polarity insensitive. |
|
| Assistant function: |
|
|
Support caller identification |
| |
Support payphone interface: polarity reversal and 16/12 kHz.metering |
|
| Safety : |
|
|
Meets ITU-T K.44 |
|
|
Last Updated on Friday, 12 December 2008 10:40 |
Products 
