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21016 SMU1-MPAB3 V1.3.doc
Installation Instructions
Warning: Upon first connection of the SMU1 to a system, the initial setting of
the 20kHz surveillance tone is set at the factory and may need to be adjusted
during system commissioning.
Wiring.
The SMU1 will normally be located on a desk or table, but is permanently
wired into a junction box/wall box/MPAB3 using the single flexible multi core
cable provided.
Wiring from the junction box to the main systems equipment may be made
with different cable types, depending on the environment and the length of the
cable run.
In any case the cable should be individually screened pairs, with an over-all
screen which must be earthed.
Fixed Installation Cable types.
Care should be taken when installing microphone cabling with respect to other
power cables and systems likely to cause interference e.g. Mains cabling,
Motors etc.
In its normal operational mode the unit is supported on a 4 pair cable.
However we would recommend using 6 twisted screen pair cable (Belden
8778).
Depending on the installation there may be a requirement to use fire resistant
or LSF cables.
Audix Systems can offer advice, based on previous experience as to suitable
cable types and maximum cable lengths.