User guide

CENTER FOR ALLIED HEALTH AND ATHLETICS FF&E April 24, 2014
SECTION 27 41 00 AUDIOVISUAL SYSTEMS
Marshall Craft Associates, Inc. 27 41 00-30
Project 12032
D. Wall plate and floor box input/output panels shall be installed with audio/ video line drivers on
runs exceeding 35ft.
E. All cabling shall be neatly strapped, dressed, and adequately supported. Any exposed
cabling shall be neatly enclosed in a protective covering.
F. Terminal blocks, boards, strips, or connectors shall be furnished for all cables, which
interface, with racks, cabinets, consoles, or equipment modules.
G. All audio signal lines shall be balanced at AV I/O plates. Provide ninety (90) degree
connector adapters for all AV cabling at custom AV I/O plates.
H. All cables shall be grouped according to the signals being carried. In order to reduce signal
contamination, separate groups shall be formed for the following cables:
1. Power cables
2. RGBHV, Video cables and Control cables
3. Data cables (when applicable)
4. Audio cables carrying low level signals
5. Audio cables carrying line and high level signals
I. Supply cables as required to meet system performance standards. Any cabling installed in
walls or ceilings shall be plenum rated. All cables shall be cut to the length dictated by the
run plus the required service loop to permit future equipment movement and relocation. For
equipment mounted in drawers or on slides, the interconnecting cables shall be provided with
a service loop of appropriate length.
J. No cable shall be installed with a bend radius less than that recommended by the cable
manufacturer. Notify the construction manager in the event that a field condition interferes
with the proper installation of any cables or equipment.
K. Grounding Procedures: In order to minimize problems resulting from improper grounding and
to achieve maximum signal-to-noise ratios, the following grounding procedures shall be
adhered to:
1. General: Because of the great number of possible variations in grounding systems,
follow good engineering practice, as specified herein, and to deviate from these
practices only when necessary to minimize crosstalk and to maximize signal-to-noise
ratios in the audio, video, and control systems. Inform the Consultant in the event that
there is a deviation from the standard grounding practices prior to actually performing
the work.
2. System Ground: A single “system ground” shall be established for the system. All
grounding conductors shall connect to this system ground. The system ground shall be
provided in the equipment rack, and shall consist of a copper bar of sufficient size to
accommodate all secondary ground conductors.
3. A copper conductor, having a maximum of 0.1 Ohms total resistance, shall connect the
system ground bar to the nearest grounded, metallic electrical conduit of at least 2
inches in diameter. Be responsible for determining if the metallic conduit is properly
electrically bonded to the building ground system, and shall show the grounding path of
a document that is provided with the system documentation.
4. Secondary system grounding conductors shall be provided from all ungrounded
equipment in each area, to the primary system grounding point for the area. Each of
these grounding conductors shall have a maximum of 0.1 Ohms total resistance.
5. Under no conditions shall the AC neutral conductor, either in the power panel or in a
receptacle outlet, be used for a system ground.