Black Box LR1530A-EU-R3, LR1530A-R3 manual T1/E1 Module

Servicing Information

The LXT411 CSU/DSU link connection is set to operate at 64 Kbps by default. The link may be set to 56 Kbps via the software menus if required.

When two CSU/DSU link routers are to be connected via a leased line in a back to back set-up, the unit must be set to 56 Kbps link speed and a null-modem crossover cable used for the connection.

A DSU/CSU crossover cable would be constructed as follows:

1 --> 7

2 --> 8

7 --> 1

8 --> 2

T1/E1 Module:

Routers with a T1/E1 interface module use a standard RJ45 service connector, pinout specification RJ48C.

T1/E1

Figure C-5 Rear View of the T1/E1 Connector

When two T1/E1 routers are to be connected in a back to back set-up, a null-modem crossover cable used for the connection.

A T1/E1 crossover cable would be constructed as follows:

1 --> 4

2 --> 5

5 --> 2

4 --> 1

Pins 1 and 2 are receive (1 = ring, 2= tip)

Pins 4 and 5 are transmit (4 = ring, 5= tip)

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