Maximum no. of nodes!!!

Hello everyone!
Amir here! i am working on an application in which am using Xbee Znet2.5 module(API Mode) as coordinator and Xbee Znet2.5 module(AT mode) as routers. Initially the system runs fine till routers are about 12 to 15 but when I further increase no. of routers the coordinator become unable to detect all of the modules and ATND command didn’t return addresses of all modules, every time it drops some of them.
Where lies the fault? Am i doing something wrong or is there some limitation of maximum number of nodes in Xbee Network? Remember there is no END-Device in my NW.

Regards,
Amir

Hello Amir,

Before going any further, is it possible for you to upgrade to ZB? The ZNET 2.5 was a precursor to the ZB firmware. Instructions can be found here:
http://www.digi.com/support/kbase/kbaseresultdetl.jsp?id=3025