RTS SSA-424A User Manual
Page 15
11
4-Wire Call Signal Connections
Call Signal Connections for other 4-wire
Communications Systems
4-wire Call Send and Call Enable/Inhibit
The SSA-424A accepts a switch-contact input from the
4-wire system and then generates a call signal output to the
2-wire system. The SSA-424A also accepts an optional
switch contact input to enable or inhibit call signaling
between the 4-wire and 2-wire systems. Figure 6 shows the
typical connections.
4-wire Call Receive
The SSA-424A receives call signals from the 2-wire system,
then converts this to relay contact closure for use as a 4-wire
call receive indication. The SSA-424A also provides +5
VDC which can be connected to the relay contacts to
generate a DC output signal instead of a contact closure.
Connections for a simple contact are shown in Figure 7 on
page 12.
15
31
47
63
35
10
37
16
32
48
64
36
11
12
a. Dependent on UIO-256 DIP Switch SW1 Settings for Input/Output Range as summarized in the UIO-256 manual.
TABLE 3.
UIO-256 GPI Outputs Connector (J5)
GPI OUTPUT NUMBERS
a
RELAY CONTACT PIN NUMBERS
UIO-256
FRAME #1
UIO-256
FRAME #2
UIO-256
FRAME #3
UIO-256
FRAME #4
NORMAL
CLOSED (NC)
CONTACT
COMMON
CONTACT
NORMAL
OPEN (NO)
CONTACT
FIGURE 6. Typical call send and call enable/inhibit connections for
a 4-wire intercom system.