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201401/IvxIM_v2.2
JBL Intellivox Installation Manual
FAILURE MONITORING ON 70 V/100 V
CONNECTION.
If the Intellivox is equipped with an input module that
supports direct interfacing to a 70 V/100 V signal, a simple
failure monitoring scheme requiring no additional
connections can be easily implemented.
This scheme is based on impedance switching of the first 70
V/100 V input. An amplifier that is driving this input should
be capable of detecting changes in connected impedance.
Impedance switching is supported for input boards PCB960
(see fig 16) and PCB124 (see fig 17). Configuration details
of the impedance switching are depending on the input
board type as described hereafter.
Reconfiguring the failure monitoring requires
access to an internal jumper.
This requires the electronics module to be carefully
removed from the enclosure by a qualified engineer.
Ensure that all connectors are unplugged before removing
the electronics module.
Configuring PCB960
The impedance between pin 1 and 2 of the audio input
connector has two states:
• High impedance (approximately 100 kOhm @ DC).
• Low impedance (approximately 2.2 kOhm @ DC).
The states are switched by a separate change-over contact
of the Intellivox's internal Failure Relay.
An internal jumper (JMP1) on the input board determines
the impedance states:
• Low impedance if the device status is OK, High
impedance if the device has a failure or is not powered. This
is the factory default configuration, the jumper is placed on
the contact pins of JMP1 that are closest to CONN1
(furthest away from the edge of the board, see fig 16).
• High impedance if the device status is OK, Low
impedance if the device has a failure or is not powered. The
jumper should be placed on the contact pins of JMP1
closest to the edge of the board.
• Always High impedance, regardless of the device status.
The jumper should be removed.
CONFIGURATION
JMP1
NOTES
High-impedance on failure
Towards CONN1
Factory default
Low-impedance on failure
Towards PCB edge
-
Always High-impedance
Removed
-
fig.16 - Input board PCB960 with location of
jumper JMP1
