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201401/IvxIM_v2.2
JBL Intellivox Installation Manual
Configuring PCB124
The impedance between pin 1 and 2 of the audio input
connector has two states:
• High impedance (approximately 140 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 (JMP2) 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 both contact pins of JMP2 (see fig 17).
• Always High impedance, regardless of the device status.
The jumper should be removed.
Notes
• The fault conditions that result in impedance switching
are user definable (these are the same as for the internal
Failure Relay, see section Fault Monitoring on page 13 for
details).
• The High impedance state is affected by the option 'DC
blocking' (as for example offered by part # 381005). In
case of the 'DC blocking' option, series capacitors result
in a very high input impedance for DC. The Low
impedance state is not affected by the 'DC blocking'
option.
CONFIGURATION
JMP2
NOTES
High-impedance on failure
Present
Factory default
Always High-impedance
Removed
-
fig.17 - Input board PCB124 with location of
jumpers JMP1 and JMP2
