| Hi oldie,
ELU28/3 is a board for digital extension lines used in the PABX ASB 501. Each board can connect up to 16 digital 2 wire 2B+D extension lines. The board contains filters and over-voltage protection for each of the lines.
The ELU28/3 occupies 16 or 32 time-slots of the switch. The selection is done with a parameter of the software signal ACTVTB. If 16 time-slots are selected, only the B1 channels are used and if 32 time-slots are selected the B channels are situated the following way, 16 B1 and then 16 B2.
The differences from ELU28/2 is that ELU28/3 can also handle enhanced signalling on the extension line. ELU28/3 is functionally backwards compatible with ELU28/2.
ELU28/1 is an older version of the system. Only ELU28/2 and /3 are interchangable.
Regards,
Sepay |