We have a the NEC Electra Elite IPKII with Dterm 80s that we took over from a contract, so now with no support.

I need to change some of the stations to ring as operator. I see that every station that rings has a Line Key (which lights up with all incoming calls that get past the auto attendant to the operator) assigned to something displayed as "ICM 250" on the screen when I do a 751 service code at the station. I do not see where that is in the manual to set for a station that does not ring.

Can someone tell me how to set a station to ring?