Nortel Communication Server 1000S Installation And Configuration Manual page 349

4 Slowly lower the daughterboard toward the NTBK50, keeping the
standoffs in line with all four holes, until the holes rest atop the four
standoffs.
If more than slight pressure is required at this point, the connector pins
might not be aligned with the connector socket. If so, lift the
daughterboard off the NTBK50 and return to step 2.
5 Gently apply pressure along the edge of the board where the connector is
located until the standoffs at the two corners adjacent to the connector
snap into a locked position. Then press down on the two corners on the
opposite side until they lock into place.
ISDN Primary Rate Interface
2.0 Mb PRI implementation
Installation and Configuration
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