Optical Systems OSD840 SERIES, Руководство оператора

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OPTICAL SYSTEMS DESIGN
DOC ID: 10104804.doc
OSD840 OPERATOR MANUAL
PAGE 15
2.3.3 INTERCOM FUNCTION
This section applies to both the OSD840T and OSD840R.
The Intercom makes use of Audio Channel 2. The Intercom is connected via the RJ11 6-pin socket on
the front panel or case. When a 2-wire phone handset is connected to the RJ11 connector, Audio
Channel 2 is automatically reconfigured to the Intercom function. The phones may be ‘hot plugged’.
While the Intercom is enabled Audio Channel 2 cannot be used for any other purpose. When a handset
is connected at one end of the link only, it may be used to
page the opposite end of the link if an
appropriate amplifier and speaker are connected.
When a handset is connected to each of the OSD840T and OSD840R, a conventional Intercom circuit is
established. If one handset is in the "OFF HOOK" state, a tone is emitted from the ‘ON HOOK’ handset
at the opposite end of the link, provided they were both ‘ON HOOK’ to start with. When both handsets
are ‘OFF HOOK’, the phone link may be used. When one phone handset is returned to the ‘ON HOOK’
state, it does not cause a tone at the opposite end, and may again be taken ‘OFF HOOK’ to re-establish
the connection. Both phone handsets must be returned to the ‘ON HOOK’ state for tone signaling to be
re-enabled. Pin 5 of RJ11 is connected to an open collector NPN transistor that is turned on when
remote end is signaling. Pin 2 of RJ11 is connected to +9V via a 100
Ω
current limiting resistor. The
RJ11 connections can be used to power an external sonalert.
FIGURE 6: RJ11 PINOUT CONFIGURATION
2.3.4 CONTROLS
The OSD840T and OSD420R each has a 4-way DIP switch (located at the front panel for Card Version
and front of box for Case Version – see Figure 6) which is used to select RS422 or RS485 mode, with
different RS485 Turnaround Delay settings from 30uSec to 80mSec. See Table 6.
There are 7 link settings available for setting up desired output configurations for AUDIO, RS232 &
RS422 outputs. Refer to section 2.2.5.
1 2 3 4 5 6
1 – N/C
2 – +9V
3 – Audio
4 – GND
5 – Sonalert
6 – N/C