Rane HAL1x, System Installation Manual

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The orange pair is reserved for data communications between the RAD and HAL. Data communications is
needed for such things as sending configuration information from HAL to the RAD, sending firmware
updates from HAL to the RAD, and sending status information from the RAD to HAL.
NOTE
: Configuration information for a specific RAD (for example, LED intensity, microphone sensitivity,
and RAD and channel names) is stored in the HAL device, not in the RAD. This makes it easy to swap in a
new RAD, if necessary, without losing configuration data.
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The green and blue pairs carry two channels each of balanced, differential, digital audio. Tx refers to audio
that the RAD sends to the HAL. Rx refers to audio that the RAD receives from HAL.
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The brown pair provides 24 VDC power and ground for the RAD. This is (obviously) the wire you should
check if it appears a RAD is not receiving power.
NOTE
: Digital Remotes (discussed on page 43) use only the orange pair (for data communications) and the
brown pair (for power).
RAD Grounding
Careful grounding of RADs is important for optimum performance. Except for the DR4, all RADs and DRs are
powered from the +24 VDC & Ground twisted pair located within the shielded CAT 5e (or better) cable con-
necting them to the HAL system of multiprocessors. The exposed metal of all RADs and DRs is connected to the
ground conductor inside the cable and to the cable shield when properly terminated. The shield conductor and the
ground twist are in parallel and are connected together at both cable ends. Except for the RAD16z, this in turn con-
nects the HAL/audio equipment rack grounding point and the metal (if used) junction box mounting the RADs
and DRs.
NOTE
:
For some electrical systems (e.g., isolated grounding systems - sometimes called a single point or star
ground) the grounding procedure outlined above may short two fingers of the building ground system. If this
creates a problem, then use of non-conductive junction boxes, or insulating mounting methods are rec-
ommended (or very much required!).
NOTE
: The RAD16z is grounded differently than the above. The RAD16z galvanicaly isolates its RJ-45 jack,
cable shield and grounded twist, and the HAL/equipment room ground from its logic and audio I/O grounds.
This means no special ground is needed. This provides 500-volts galvanic isolation as well as standard Eth-
HAL SYSTEM INSTALL GUIDE
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