Specifications
Front Panel
61189500L1-1F 4-9
FXS Port
The FXS port (MX412 only) provides a 2-wire analog interface between a Voice Frequency (VF)
transmission and a signaling facility. The FXS interface provides for simultaneous signaling in
each direction for use with 2-wire off-premises station lines, carrier extended PBX trunks, or
subscriber line foreign exchanges using a loop start signaling system. FXS options are listed
in Table 4-6.
WARNING
The FXS Port interface must not be metallically connected to
interfaces which connect to the OSP or its wiring. The FXS
interface is designed for use as an intra-building interface only.
The addition of Primary Protectors is not sufficient protection in
order to connect the FXS interface metallically to OSP wiring.
PSU Slots (MX410 Only)
The MX410 houses up to two hot-swappable PSUs that can provide power redundancy. At
least one PSU (P/N 1189501L1) must be inserted into the MX410 for the system to function.
To remove a PSU, remove the screws that hold it in place and carefully pull the PSU straight
out of the MX410. A blank PSU cover (P/N 1189502L1) should be used to cover an unused
PSU slot. After power is applied and a PSU is inserted, refer to “LED Indicators” on page 4-10
for the MX410 status.
The MX412 contains an internal power supply.
Table 4-6. FXS Options
Mode Description
Loop Start Selects ANSI T1.403 FXS Loop Start mode of operation.
PLAR D4 Selects Private Line Automatic Ringdown where onhook = 00.
Signaling must match the PLAR unit at the distant end.
PLAR D3 Selects Private Line Automatic Ringdown where onhook = 11.
Signaling must match the PLAR unit at the distant end.
FX Ringdown PLAR mode of operation that allows for an FXS Loop Start unit on the
distant end.










