Revision B • 7/00
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9
2 Installation
LOGIC CONNECTIONS
Each Input module comes standard with one
24-pin logic connector to control a device con-
nected to either the A or B input. The optional 99-
1003 Dual Logic Interface plug-in can be added
to any Input module to provide a separate logic
connection for each input.
When a peripheral device is connected, one of
the main functions of the logic interface is to start
the peripheral at module on. The peripheral de-
vice logic can, in turn, control the Input module;
turning the module audio off at the end of an event
and then controlling the Off lamp illumination to
indicate the peripheral device status.
When a Guest Panel is connected, its remote
On, Off, Cough and Talkback buttons control the
module while the logic control outputs from the
module control the button tallies in the Guest
Panel.
THE LOGIC INTERFACE
A simplified schematic for the Input module
interface is shown below. The dual logic plug-in is
identical. Logic outputs (shown on the right) are
isolated from peripheral devices by five solid-state
devices functioning like single-pole mechanical re-
lays. The “relay contacts” can switch external volt-
ages of up to 60 volts at 350 mA.
Each press of the On button generates a 220
ms pulse from the Start Pulse relay. Each press of
the Off button generates a 220 ms pulse from the
Stop Pulse relay. These two relays are commoned
together at Command Common. The other three
relays, Logic Active Tally, On Tally and Off Tally,
are also “commoned” together at the Tally Com-
mon output.
The six logic inputs (on the left side of the illus-
tration) are opto-isolated and current limited so
any logic voltage from +5 to +40 VDC can be used.
Notes:
LM317 used as current limiting device
Opto-Isolator inputs can 5 to +40 VDC logic
Opto-Isolator outputs can handle up to 60 volts at 350 mA
Jumper E1 to E2 to continuously ac5 Logic power.
n/c
Audio Reset (+)
Ready (+)
J3
J3
J3
J3
J3
J3 18
19
21
Ready (-)
Audio Reset (-)
Ext. Control In (+)
LM317
LM317
LM317
LM317
LM317
J3
J3
J3
J3 20
9
7
8
On (-)
Off (-)
Cough (-)
Talkback (-)
24
22
23
13
15
4
5 J3
J3
J3
J3
Start Pulse
Stop Pulse
Command Common
Logic Active Tally
J3
J3
J3
J3
J3
J3
Logic Ground
Logic Ground
Logic Ground
Off Tally
Tally Common
On Tally
17
16
14
1
2
3
12
11
10
6 J3
J3
J3
J3 +5 Logic
+5 Logic
+5 Logic
+5 Logic
+5
Reg.
V+12D
LM317
Inter
nal Logic
E2
E1
Simplified Schematic, Input Module Logic Interface
