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201401/IvxIM_v2.2
JBL Intellivox Installation Manual
FAILURE RELAY CONFIGURATION
Intellivox units equipped with input board PCB124 (see
fig.17) support configuration of the internal Failure Relay
for either volt-free or impedance-sensing (10k / 20k Ω)
operation.
Reconfiguring the internal Failure Relay
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.
An internal jumper on the input board (JMP1) defines
the operation:
• Volt-free mode:
In volt-free operation, COM is connected to NC; a
failure condition causes COM to be connected to NO.
This is the factory default configuration, the jumper is
placed on the contact pins of JMP1 that are closest to
R29 (furthest away from the edge of the board, see fig 17).
• Impedance sensing mode:
When configured for impedance-sensing use, the
impedance between COM and NC is 10k Ω and open-
circuit between COM and NO in normal operation.
When a fault condition occurs, the impedance between
COM and NC rises to 20k Ω, and COM is short-circuited
to NO. The jumper should be placed on the contact pins
of JMP1 closest to the edge of the board.
NO
NC
COM
Connect to NO or
NC as required
INTERNAL RELAY
VOLT-FREE
CONFIGURATION
NOTE: Relay shown in
energised state - i.e., ‘no
fault’.
fig.18 - Volt-free mode
2 x 10 k
Ω
INTERNAL RELAY
IMPEDANCE-SENSING
CONFIGURATION
NOTE: Relay shown in
energised state - i.e., ‘no
fault’.
NO
NC
COM
fig.19 - Impedance-sensing mode
CONFIGURATION
JMP1
NOTES
Volt-free
Towards R29
Factory default
Impedance-sensing
Towards PCB edge -
