The Nortel OM (Optical Metro) platform is a legacy Add–Drop Mux (ADM) for SDH and also supports Ethernet over SDH.

The 4150 is a combination of STM-4 and STM-16 ADM with STM-4 aggregate cards whereas the 4200 is an STM-16 mux with DWDM interfaces. They are both used for metro and regional SDH applications. Typical cards for repair include the aggregate card NTEU25AA which is for shorthaul STM-16 using 1310nm and also NTEU25DH which is the long haul variant using 1500 nm wavelength. The multiplexer/ aggregate cards and the tributary cards are inter-changeable across the OM 4150 and OM 4200. In common with other SDH equipment, the OM 4K can function as ADM, Regenerator and small cross connect.

Nortel OM 4150 and 4200 Repair

Nortel OM 4150 reference system in the TXO repair centre


The Nortel OM 4150 reference system is used to test and screen cards for OM 4150 and OM 4200 such as STM-16  card (centre) and STM-4 and STM-1 aggregate cards (left). The service includes post-repair traffic testing to ensure that our engineers are completely happy with the optical parameters and traffic flow before return shipping to the customer.


Part Code  Description
NTEU15AA STM-4 Trib Card
NTEU10AA STM-1 Trib Card
NTEU25AA STM-16 Aggregate card SH 1310nm
NTEU25DH STM-16 Aggregate card LH 1500nm


To discuss your needs for repair of equipment belonging to the Nortel 4150 and 4200 systems please contact us.

TXO has no formal affiliation with Ciena in relation to repair services.