SAFETY INSTRUCTIONS
– 3 –
NWA-008841-001 Rev.5.0
90ch0001.fm
(20) For Digital interfaces, a CSU/DSU may be required for proper operation. When choosing a CSU/
DSU, make sure that it is provided with suitable lightning protection. If this is not the case, gas tube
arresters as specified elsewhere in this manual (b) must be connected to the involved interface wiring.
NOTE:
The Ethernet ports are not intended to be connected directly to outdoor cables.
(21) When installing the LC card for providing the analog telephone interface that is connected to off-
premise site, use PN-4LLCB card.
(22) Do not install the PN-2ODTB/PN-4ODTA card for providing the analog trunk interface that is
connected to off-premise site.
PBX
RA
RB
TA
TB
PRT/BRT/DTI/CCT
G
CSU : Customer Service Unit
DSU : Digital Service Unit
MDF : Main Distribution Frame
RECEIVE
OFF-PREMISE
To Digital
Network
MDF
CSU/DSU
TRANSMIT