GAI-Tronics 12594-001 Redundant AZI Switching Module - Manual (Page 5)

Pub. 42004-406A
Model 12594-001 Redundant AZI Switching Module Page: 5 of 7
\\s_eng\gtcproddocs\standard ioms - current release\42004 instr. manuals\42004-406a.doc
04/08
Operation
The module has essentially two modes of operation, normal and fault. Each mode is described in detail
below.
Data line terminals JBT3 and JBT5 are not affected by the module’s switching action. They are simply
pass-through terminals for the RS-485 data lines from the AZI card connectors. JTB3 connects to the
Secondary AZI card (J2) and JTB5 connects to the Primary AZI card (J1).
Audio line terminals JBT8 and JBT9 are not affected by the boards switching action. They are simply
pass-through terminals for the audio line #6 from the AZI card connectors. JTB8 connects to the Primary
AZI card (J1) and JTB9 connects to the Secondary AZI card (J2).
Normal Condition
All relays on this module are de-energized. The Primary AZI card’s audio (J1) is connected to audio
output terminals (JTB4). The Secondary AZI card’s audio (J2) is disconnected from the audio output
terminals (JTB4).
Fault Condition
A fault condition is signaled by connecting either terminal of JBT6 to 12 V dc (-). LED1 (Pri-Active) or
LED2 (Sec-Active) illuminates to indicate the active input. In an ADVANCE system application, these
inputs are active if a primary MCU or primary AMI fault occurs. The control signal input is supplied by
an external relay contact.
When activated, relays K1–K7 are energized. Relay K1 contacts are wired to JBT7 and will change state
for the duration of the active condition. Relays K2–K7 switch the Secondary AZI card’s audio (J2) to the
audio output terminals (JTB4). The Primary AZI card’s audio (J1) is disconnected from the audio output
terminals (JTB4).