Nortel Networks 553-3001-211 manual 266 of 894 NT5D33 and NT5D34 Lineside E1 Interface cards

Page 266 of 894 NT5D33 and NT5D34 Lineside E1 Interface cards

CPE at the far-end will likewise have transmit and receive wired straight from the RJ48 demarc at the far-end of the carrier facility.

For 75 ohm coaxial installations, E1 signaling for all 30 channels is transmitted over P2 connector pins 1, 3, 9, and 11 though an adapter and out two coaxial connectors Tx (transmit) and Rx (receive). Tx is the LEI output, and Rx is the LEI input from the E1 stream. E1 transmit and receive pairs must be turned over between the LEI and the CPE that is hardwired without carrier facilities. If the LEI is connected through E1 carrier facilities, the transmit and receive pairs must be wired straight through to the RJ48 at the Telco demarc, the LTU, or other E1 carrier equipment. The E1 CPE at the far end will likewise have Tx and Rx wired straight from the RJ48 demarc at the far end of the carrier facility.

External Alarm Connections

P3 connector pins 1, 2 and 3 can be plugged into any external alarm-sensing hardware. Plug the DB9 male connector labeled “P3” into an external alarm. These connections are optional, and the LEI functionality is not affected if they are not made.

The MMI monitors the E1 link for specified performance criteria and reports on problems detected. One of the ways it can report information is through this external alarm connection. If connected, the LEI’s microprocessor will activate the external alarm hardware if it detects certain E1 link problems it has classified as alarm levels 1 or 2. See “Man-Machine E1 maintenance interface software” on page 272 for a detailed description of alarm levels and configuration. If an alarm level 1 or 2 is detected by the MMI, the LEI will close the contact that is normally open, and will open the contact that is normally closed. The MMI command “Clear Alarm” will return the alarm contacts to their normal state.

MMI Connections

P5 connector pins 2, 3, 5, 7 and 9 are used to connect the LEI to the MMI terminal, connecting LEIs in a daisy chain for access to a shared MMI terminal. When logging into a LEI, “control 2” is asserted by that card, which informs all of the other cards not to talk on the bus, but rather to pass the data straight through. The pins labeled “control 1” are reserved for future use. As with the external alarm connections, MMI connections are optional. Up to

553-3001-211 Standard 2.00 September 2004