f502.02:201x rack design for audiovisual (av) systems ... · 10 this standard covers the...

F502.02:201X

Rack Design for Audiovisual (AV) Systems

AVIXA DRAFT Standard

Town Hall Review Draft

June 4, 2019

ICS Code:

NOTICE: This AVIXA International draft is for the use of Rack Design task group members only. It is not for public disclosure and is not to be copied, disseminated, shown to, distributed to, or shared with any other person or entity. The draft is dynamic in nature and is subject to change.

Abstract

Draft Standard AVIXA F502.02 – Rack Design for Audiovisual (AV) Systems

© 2019 by AVIXA® DRAFT STANDARD

Foreword [to be inserted]

Task Group info [to be inserted]

TABLE OF CONTENTS

[to be inserted]



1 SCOPE 1

This Standard defines the requirements for designing equipment into an AV equipment rack; 2 details the requirements for collecting design input information; and defines the required 3 design output information. 4

It can be applied to: 5

a) Systems to be built into racks according to IEC 60297-3-100 (482,6mm or 19 inches) 6 requirements. 7

b) Systems to be built into ‘half rack’ or other sizes at the user’s discretion. 8

Purpose 9

This standard covers the fundamental processes and decision making for designing 10 equipment into a reliable AV equipment rack regardless of location, including: 11

a) Rack selection, thermal management, associated options, accessories, and security 12 requirements in single and multi-rack installations. 13

b) Rack elevations. 14

c) Power management and distribution. 15

d) Earthing (grounding) and bonding requirements. 16

e) Verification prior to rack build. 17

Design input information that should be available to achieve an agreed-upon outcome prior to 18 designing the rack includes: 19

a) Equipment selection 20

b) System design documentation 21

c) Rack location/environment 22

d) Security requirements 23

NOTE: Network security is not considered part of this standard. 24

e) Entry/connection method for site cabling 25

Where AV equipment is being installed in a rack that contains non-AV equipment, the rack 26 design shall be undertaken as a holistic process including requirements for the non-AV 27 equipment. 28

Application 29

This standard applies to systems designed to be built into racks that have been manufactured 30 according to basic dimensions as outlined in IEC 60297-3-100 (482.6mm or 19 inches). It may 31 be applied to systems designed to be built into ‘half width rack’ or other sizes at the user’s 32 discretion. It can be used by all parties affiliated with the building phase – consultants, system 33 designers, system engineers, manufacturers, technology support staff, end users and 34 verification agencies – to support proper design of an AV equipment rack. 35

36



Exclusions 37

This Standard does not apply to designs for: 38

a) AV equipment to be installed outside of AV racks. 39

b) Racks that do not include AV equipment. 40

c) Rack design requirements for extreme conditions outside the general operating 41 range (e.g., security, humidity, temperature, altitude) 42

43

2 REFERENCES 44

To be inserted. 45

46

3 TERMS & DEFINITIONS 47

This Standard uses système international d'unités (SI) units throughout. Design tools may use 48 alternative units with appropriate conversion. 49

Definitions 50

active thermal management 51

Provision of active cooling solutions such as forced air through a fan or blower, forced liquid, 52 and thermoelectric coolers (TECs), which can be used to optimize thermal management within 53 an AV rack. Active thermal management is used when natural convection is insufficient to 54 remove heat. 55

passive thermal management 56

Passive cooling relies on natural convection and heat dissipation through airflow without the 57 use of active cooling equipment 58

bonding (equipotential bonding) 59

Provision of electric connections between conductive parts, intended to achieve 60 equipotentiality 61

design input checklist 62

A document used to identify the required design inputs and to verify that those inputs have 63 been received and considered. 64

earthing/grounding (protective earthing/grounding) 65

Earthing/grounding a point or points in a system or in an installation or in equipment, for 66 purposes of electrical safety. ‘earthing/grounding’ is taken as connection to the general mass 67 of Earth, the potential of which is conventionally taken as zero. 68

ergonomics (placement, serviceability) 69

How equipment and furniture can be arranged so that people can do work or other activities 70 more efficiently and comfortably. 71

client requirements 72



Any specific requirements relating to the design of the AV system that the client has defined 73 and need to be included as design inputs. 74

mandatory certification 75

A required, obligatory, or compulsory certification relating to the AV rack design. 76

optional certification 77

A certification that is not required by local or federal jurisdictions but may be requested or 78 desired to show quality of design and implementation. 79

regulatory requirements 80

Requirements necessary to meet local laws, codes or regulations in the region where the AV 81 rack is being installed. 82

controlled environment 83

A rack location which is maintained at a defined, constant and controlled temperature and 84 humidity. for example, by means of an automatic air conditioning system. 85

non-controlled environment 86

A rack location that has no means of actively controlling the overall environment. 87

internal cabling 88

Any cabling forming part of the AV system that is wholly contained within a single rack. 89

90

Figure 1 Internal cabling 91

inter-rack cabling 92

Any cabling forming part of the AV system that is passed from one rack to another in a ganged 93 or multi-rack installation. 94

95



96

Figure 2 Inter-rack cabling 97

external cabling 98

Any cabling forming part of the AV system that is not wholly contained within the rack(s). 99

100

Figure 3 external cabling 101

rack designer 102

The skilled AV design professional carrying out the detailed design of the AV rack. 103

rack unit (RU or U) 104

One rack unit shall be as defined in IEC 60297-3-100: 1 rack unit = 44.45 mm (1.75 inch) 105 height. 106

rack mountable 107

AV equipment that is designed to be mounted within an equipment rack conforming to IEC 108 60297-3-100, and has a front panel mounting ears/wings with a height in multiples of 1 rack 109 unit. This definition includes an assembly of smaller modules forming a complete rack-110 mountable unit. 111

secure location 112

A location containing an AV rack that is secured by other physical means such as a tumbler 113 lock, electronic card/keypad access, biometric security, etc. 114



service and maintenance installer 115

The person(s) that would carry out servicing and maintenance, perform updates and other 116 functions to keep the system running. 117

system operator 118

The person(s) that will operate or use the system that is installed - also referred to as the end 119 user 120

system operator accessibility 121

The ability for the system user to have contact, or admittance, to the equipment controls 122 necessary for using the system. 123

tail 124

Cabling that makes the transition between internal cabling and external cabling by means of 125 either a fixed connection panel mounted outside of the rack, or loose in-line connections to 126 the external cabling. Rack tails are fixed at the rack end and continue inside the rack as part 127 of the internal cabling. The other end is free to connect to the fixed panel or in-line connections. 128

usable rack height 129

The amount of space available for fixing rack-mountable equipment. Stated in RUs. 130

overall rack height 131

The total height of the AV rack. Includes usable rack height plus the height of the rack frame 132 itself, castors, mounting plinth, fan trays, etc. 133



134

4 RACK DESIGN PROCESS OVERVIEW 135

The process for designing an equipment rack to meet this Standard requires several design 136 parameters to be considered. These are referred to as design inputs and may include factors 137 relating to client needs, regulatory requirements, environmental, security, and electrical 138 elements as well as the functional and technical requirements for the system itself. All 139 applicable information relating to these factors must be gathered prior to commencing the rack 140 design. 141

The design of the rack may be constrained by one or more of the design inputs. As part of 142 gathering the design inputs the rack designer shall identify where constraints apply and shall 143 design within these constraints. Where a design is not constrained by a particular factor, then 144 a design input may not be needed. This shall be identified on the design input checklist. 145

The rack design process can then take place, and this will produce several design outputs, 146 detailing all elements necessary to fully define what needs to be built. These include rack 147 type, rack elevations, thermal management provisions, cabling, electrical and security 148 requirements. Typically, this information, in the form of a drawing pack with schedules and 149 notes would be passed to a rack builder for construction of the rack. 150

151

152

Figure 4 Rack Design Input/Output Flow 153

The process of designing a rack is complex and contains may interdependencies. The design 154 needs to be carried out in order and should follow the process as outlined in the flow chart 155 below: 156

157



Figure 5 Rack Design Process Map



Collect all input information prior to beginning the rack design. Consider every design input in relation to the design output it will affect. The relationship between design inputs and design outputs is summarized below.

DESIGN OUTPUTS RACK DEFINITION THERMAL CABLING ELECTRICAL SECURITY

VIBRATION & IMPACT

RESISTANCE

DESIGN INPUTS Typ

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CLIENT/CODE

Client Design Standards • • • • • • • • • • • • • • • • • • • • •

Local codes • • • • • • • • • •

Certification • • • • • • • • • •

SPACE PLANNING

Available space • • • • • • • • • • • •

Location • • • • • • • • • • • •

Site logistics constraints • • •

ENVIRONMENTAL

Thermal • • • • • • •

Humidity • • •

Vibration & Impact Resistance • • • • • •

Acoustic Sensitivity • • •

SYSTEM DESIGN

Equipment list • • • • • • •

Documentation • • • •

Heat load • • •

Power reqs (by system) • • • • • •

ELECTRICAL

Power supply capacity • • • •

Quantity, type of supplies (inc. UPS) • • • •

Connection method • • •

SECURITY Physical Security • • • • • • •

Figure 6 Rack Design I/O Matrix



5 DESIGN INPUTS 1

All design inputs shall be ascertained prior to commencement of the rack design. Some inputs 2 will provide a constraint on a design – e.g. existing power supply arrangements, physical size 3 of the location where the rack is to be installed. These constraints shall be identified at the 4 design input stage. 5

Where elements are not pre-existing, e.g. if the project is at an early stage and other designers 6 are awaiting details from the rack designer, those elements will not be available as a design 7 input and the rack designer is free to design accordingly. Design inputs identified as being 8 unavailable or not applicable shall be identified as N/A on the design verification checklist. 9

Regulatory / Client requirements 10

The rack designer shall research regulatory requirements and mandatory certifications 11 required at the intended rack location. The rack designer shall ask the client if they have any 12 requirements that must be included in the design, or if they require any options certifications 13 to be designed to. 14

The rack design shall meet or exceed requirements in the following order of priority. 15

1. Regulatory Requirements 16

2. Mandatory Certifications 17

3. Client Requirements 18

4. Optional Certifications 19

System design 20

The minimum system design inputs that shall be completed prior to the rack design are: 21

5.2.1 Equipment list 22

The equipment list shall state all relevant data needed to determine the minimal dimensions 23 of the needed 19" rack(s). It will also determine the power consumption, heat load and relative 24 humidity requirements of the rack(s). 25

For most equipment, the heat load can be assumed to equal the power consumption. The 26 exceptions to this include but are not limited to: audio power amplifiers, remote power 27 supplies, PoE switches, and other central equipment that powers remote devices. For this 28 equipment the designer shall refer to the manufacturers’ documentation to determine the heat 29 output. 30

The equipment list shall contain the following information for each piece of equipment to be 31 housed in the rack: 32

Item reference 33

Asset ID/inventory number (if used on the project) 34

Manufacturer 35

Model 36

If the equipment is rack-mountable? (Yes/No) 37



Width (if not rack mountable – leave blank if rack-mountable) 38

Height (in RU if rack-mountable, mm*) 39

Depth (in mm*) 40

Electrical power consumption (Watts) 41

Heat Output (Watts*) 42

Minimum operating temperature (Degrees C*) 43

Maximum operating temperature (Degrees C*) 44

Minimum relative humidity (%) 45

Maximum relative humidity (%) 46

See Annex D for a sample equipment list. This is available in spreadsheet format with 47 supporting design calculations and can be downloaded here: [insert hyperlink]. 48

* SI units are cited as part of this standard. Alternative units may be used if more suited to the 49 region. The equipment list template spreadsheet supports metric (SI) and imperial units. 50

NB: If multiple units (such as half- or quarter-rack modules) form a single rack-mountable unit 51 this should be recorded as a single item on the equipment list with the total power/heat 52 requirement of all sub-units identified. 53

The equipment list shall include allowances for venting/blanking panels, fan trays/thermal 54 management products, and shelves for rack-mountable equipment. 55

5.2.2 System Design Documentation 56

The rack designer shall obtain the system design documentation. The design documentation 57 shall identify: 58

a) All equipment forming part of the system(s) to be installed in the AV rack(s) (including 59 any non-AV equipment to be accommodated. 60

b) Which equipment is housed within the AV rack(s)? 61

c) Internal cabling between all equipment in the AV rack(s). 62

d) External cabling connections for all equipment in the AV rack(s). 63

e) Inter-rack cabling requirements for all equipment in the AV racks (if applicable). 64

5.2.3 Other Design Information 65

Other design information that may be required to complete the rack design shall be obtained 66 by the rack designer, such as: 67

a) Cable planning including: 68

Cable types and terminations; 69

Cable labeling; 70

Volume of cabling; 71

Cable separation (See Table on Cable Separation); 72



Cable location; and 73

Cable entry points. 74

b) Equipment labeling. 75

c) Intended rack labeling (if known). 76

d) Aesthetic requirements. 77

Electrical 78

The equipment list shall state the power consumption of the separate components. This will 79 determine the minimum rating of the power supply for the rack(s). 80

The following additional design inputs shall be obtained where required: 81

Determine the available power feeds to the rack: 82

a) Quantity 83

b) Supply rating of each feed 84

c) Requirements for power sequencing 85

d) Connection method 86

Define any specific earthing (grounding)/bonding and protection arrangements: 87

a) Mandatory supply earthing (according to local regulations). 88

b) Additional bonding of rack frames/components and multi-rack systems. 89

c) ‘Clean Earth’ or other signal grounding arrangements. 90

d) UPS Requirements. 91

e) Surge protection requirements. 92

Space planning 93

Design inputs for space planning considerations for the area in which the rack will be located 94 shall include: 95

a) Available space for equipment racks – height, width and depth restrictions. 96

b) Site logistics constraints including height, weight, width, and access route restrictions. 97

c) Regional regulatory requirements dictating minimum space requirements. 98

d) Accessibility requirements for disabled end users. 99

e) Accessibility for service and maintenance installer to front/rear/top/bottom/sides. 100

f) Cable entrance pathways. 101

g) Location with respect to connectivity to room components (cable length maximum 102 issues), rack swing if wall mounted, other racks or co-located equipment. 103

h) Space allowance for future expansion. 104

Once the size (total number of RU’s plus future growth space along with minimum depth of 105 components) is determined for a rack based on the components, location for placement along 106



with mounting method needs to be determined to meet several considerations of the system 107 operator and future service and maintenance requirements. 108

Table 1: Space Planning Design Input Considerations 109

Design Inputs Considerations for system operator (user)

Considerations for service and maintenance (installer)

Is system operator accessibility required •

Front clearance 1200 mm (approx. 48”) • •

Rear clearance 900 mm (approx. 36”)

Side clearance 750mm (approx. 30”)

•

•

Rack mounting height (if wall mounted) • •

Components that require frequent operation - •

Protection of non-end user components •

External cable entrance method •

Need for Securing rack to structure •

Serviceability •

- Appropriate space for possible movement • •

Front and rear door opening and approach • •

Side swing for wall mount •

- Side space for side panel access if equipped • •

Electrical and grounding connections clearances •

Mechanical cooling connections above/below rack considerations

•

Max cable length considerations for rack placement relevant to signal transmission

•

Wireless device placement for end user interface • •

Rack Location Environment 110

Design input considerations relating to the rack environment will consider both the effects of 111 the immediate surroundings on the rack(s) and those of the rack(s) on the immediate 112 surroundings. 113

5.5.1 Thermal Management 114

Based on the temperature and humidity requirements of the equipment within the rack(s), the 115 rack designer shall determine necessary actions in the design for controlled and non-116 controlled environments. 117



The minimum operating temperature/relative humidity of the highest rated piece of equipment 118 shall determine the minimum consistent internal operating temperature/relative humidity of the 119 rack. This can be determined from the equipment list. 120

The maximum operating temperature/relative humidity of the lowest rated piece of equipment 121 shall determine the maximum consistent internal operating temperature/relative humidity of 122 the rack. This can be determined from the equipment list. 123

124

In a non-controlled environment, the rack designer shall determine the necessary methods to 125 meet the thermal conditions. 126

In a controlled environment, no further action is required with regards to temperature and 127 humidity control as part of the design although the rack designer shall define the airflow within 128 the rack(s) and ensure this is adequate for the defined temperature range. The rack designer 129 shall confirm that the controlled environment can maintain the required controls with the 130 imposed load of the AV rack(s). 131

5.5.2 Airflow Criteria 132

The rack airflow shall be determined by the equipment in the rack - whether active or passive, 133 and equipment airflow direction. The equipment airflow information shall be captured in the 134 equipment list. 135

For guidance on determining the best method for airflow management based on the equipment 136 in the rack, see Annex C. 137

5.5.3 Acoustic 138

The rack designer shall determine if the rack is in an area that is sensitive to noise produced 139 by the rack. 140

A rack placed in a noise-sensitive environment may require acoustic treatment or selection of 141 a noise-suppressed rack. 142

5.5.4 Vibration and Impact Resistance 143

The rack designer shall determine if the rack(s) is (are) to be installed within a location subject 144 to vibration and impact, for example seismic activity zones (earthquakes). 145

If the rack is to be located in an area where local regulatory requirements or client 146 requirements specify a designed rack, then the correct rack type for the zone shall be 147 specified. 148

Security 149

The rack designer shall determine the physical security requirements for the AV rack. 150

Design inputs include: 151

a) Theft prevention requirements; 152

b) Equipment tampering prevention requirements; 153

c) The security of the room (rack location) itself; 154



d) System operator access requirements; 155

e) Notification requirements if the rack is accessed (access control system environments 156 only). 157

NOTE: Network security is not part of this standard. 158

A security measures flowchart is included in Annex C. 159

6 PROCESS OUTPUTS 160

All information gathered from the design input stage will define or influence the design outputs. 161 The following design outputs shall be produced, following consideration of all the relevant 162 inputs: 163

Rack definition 164

Rack definition outputs shall include: 165

a) Rack Type 166

b) Rack Size(s) 167

c) Quantity of racks 168

d) Rack elevations 169

e) Equipment mounting details 170

f) Labelling requirements 171

g) Optional components required 172

h) Weight ratings/capacity 173

174

6.1.1 Rack Type 175

The rack type should be defined as one of the following: 176

Floor standing

Wall mounted



Mobile/portable

Open frame

Slide out

2 or 4-post

Figure 7 Rack Types 177

Other requirements that may need to be specified as part of the rack type definition are: 178

a) Acoustic treatment (isolation). 179

b) Vibration and impact resistance rating 180

c) Aesthetic treatments (joinery cladding, special finishes). 181

d) Plenum rating. 182

6.1.2 Rack Size 183

Dimensions including: 184

a) Usable and overall height; 185

b) Overall width; 186

c) Usable depth for equipment (based on maximum equipment depth); and 187

d) Overall depth including allowance for cable management and power distribution. 188

189

190

191



6.1.3 Quantity 192

The quantity of racks is dictated by the amount of rack space required for equipment plus 193 future expansion. The rack designer shall determine the quantity of equipment racks based 194 on the total usable space required, site physical and logistics constraints. 195

6.1.4 Elevations 196

The rack elevation is the final stage of rack definition and can only be completed after size, 197 quantity and type have been defined. The minimum design output requirement for any rack 198 design shall be a front elevation to show equipment locations, shelves, blanking and venting 199 requirements. Additionally, side elevations should be considered to show equipment depths 200 and allowance for cable management, power distribution, cable entry, etc. 201

202

Figure 8 Example of rack elevation 203

Further elevations that should be considered may be top and rear if any detail such as input 204 plates, monitors, or connection panels are present. 205

Any non-rack mountable equipment that is not fixed on shelves shall be shown on the 206 corresponding elevation (e.g., side or rear). 207

NOTE: Specific consideration shall be given to accessibility of user-accessible AV equipment 208 within the rack and ergonomics, weight load, and distribution. 209

6.1.5 Non-Rack mountable equipment 210

Where AV equipment is not rack mountable, the design output shall specify from the following 211 methods the mounting arrangements for such equipment. 212

NOTE: Do not cover important information such as serial numbers, power input/output info, 213 power connection pin out, or part numbers. 214

6.1.6 Rack shelf 215

AV equipment shall be fully secured to the shelf, preferably with a mechanical fixing/fastener. 216



A single shelf may be used for mounting multiple AV equipment items provided the AV 217 equipment and connections remain accessible. AV equipment with user front-panel controls 218 shall be mounted at the front of the shelf with the user-interface controls facing forward. 219

6.1.7 Other Locations 220

If AV equipment is mounted elsewhere within the rack, it shall not impede access to other AV 221 equipment. 222

Acceptable locations include: 223

a) Cable trays; 224

b) Horizontal mounting or cable management rails; 225

c) Rear rack rails; or 226

d) The rack framework. 227

Equipment mounted in other locations shall be mechanically fixed/fastened in place by means 228 of a: 229

a) Fabricated bracket; 230

b) Strap; or 231

c) Bolted fixing/fastener. 232

NOTE: Fixings that are reliant on adhesives are not acceptable. 233

6.1.6 Labelling 234

The design outputs shall include requirements for: 235

a) Equipment labelling 236

b) Rack labelling 237

c) Cable Labelling 238

6.1.7 Optional components required 239

The design outputs shall include details of any additional components necessary for the 240 correct assembly and operation of the system, such as: 241

a) Doors, access panels, tops, bottoms, and sides; 242

b) Ventilation fan panels/trays, vent panels; 243

c) Cable management – trays, lacing bars, etc.; and 244

d) Cable access – gland plates, access panels, etc. 245

Thermal Management 246

The rack design output documentation shall contain the following information: 247

a) Fan requirements and locations 248

b) Temperature and/or humidity probe requirements and locations 249

c) Vent/blank panels requirements and locations 250



d) Air flow direction and interface to air conditioning systems (HVAC) 251

e) A statement of the recommended maximum and minimum internal operating 252 temperature of the rack 253

f) A statement of the recommended maximum and minimum internal operating humidity 254 of the rack 255

Cabling 256

The design outputs shall include a detailed plan for: 257

6.3.1 Internal cabling 258

a) Internal cabling location plan 259

b) Cable management – horizontal and vertical lacing 260

c) Cabling separations 261

6.3.2 Inter-rack cabling 262

a) Location plan 263

b) Cable lengths 264

c) Connection arrangements 265

6.3.3 External cabling 266

The design output shall define the details for connection of external cabling. The method shall 267 be selected from one of the following: 268

1. Hard wired – All site cabling loomed directly into the rack and only possible on site. 269 Design output documentation shall define entry point and allow space within cable 270 management within the rack. 271



272

273

2. Tail – A predetermined length loom plugged into site cables terminated on a wall panel 274 or joined under a false floor. Design output documentation shall define: 275

Entry point 276 Tail length (overall) 277 Tail splay/split length 278 Cable groupings (where multiple tails are required) 279 Tail terminations 280



281

282

3. Termination Panel – A connection panel located at the rack for terminated site cables 283 to be connected to. Design output documentation shall define: 284

Connection panel locations 285 Connection panel design – including connectors and labelling requirements 286 Any specialist connection panel terminations required 287

Termination panels shall not be too large or placed such that maintenance access is impeded. 288

289

Courtesy of XXXXX 290

Figure 9 Termination Panel Mounted to Rack 291

Electrical 292



The electrical design outputs shall provide details of all power arrangements for the rack(s) 293 including allowance for spare capacity. 294

The following information shall be provided within the design output documentation: 295

6.4.1 Power supply feed(s) 296

a) Total load for each rack 297

b) Quantity of supply connections 298

c) Capacity (current rating) of each supply 299

d) Spare capacity available/allowed for 300

e) Means of connection for each supply (connector type, cable size, cable type, cable 301 length) 302

f) UPS supply requirements (if applicable) 303

6.4.2 Internal power distribution 304

a) Type of power distribution units (horizontal/vertical, outlet types, outlet quantities) – 305 including spare capacity 306

b) Quantity of distribution units 307

c) Unit/outlet/fuse labelling 308

d) Sub-distribution arrangements and mounting details (if required) 309

e) Allocation of distribution outlets to equipment 310

f) Surge protection devices (if required) 311

g) Internal UPS devices and wiring (if required) 312

6.4.3 Earthing/ Bonding 313

a) Rack connection to earth/ground (via supply cable/via separate connection) 314

b) Rack internal bonding (side panels, doors, tops etc.) 315

c) Clean earth requirements (if applicable) 316

d) Specific signal earthing requirements (if applicable) 317

e) Static discharge prevention - additional bonding (if applicable) 318

6.4.4 DC power distribution 319

a) Quantity and type of DC power supplies 320

b) Mounting arrangements 321

c) Distribution/wiring arrangements 322

Security 323

The design outputs shall define the physical security requirements that need to be 324 incorporated into the rack(s). Such requirements may include: 325



a) Lockable rack door(s) (mechanical, card access or biometric) 326

b) Lockable side panels 327

c) Security fixing screws (anti-theft) 328

d) Equipment covers (anti-tamper) 329

e) Access activity logging requirements (electronic access control systems only) 330

Vibration and Impact Resistance 331

The design outputs shall provide details of any measures necessary to allow installation of the 332 rack into an active seismic environment. This shall include details of: 333

a) Rack fixings – fixing of rack(s) to structure of building 334

b) Equipment fixings – requirement for shake-proof fixings 335

c) Shock absorption – Requirement for rack fixings to contain shock-absorption and 336 specification of those fixings 337

Design Outputs for other designers 338

In many cases the outputs of the rack design process may need to provide information to other 339 designers or providers on a project, such as architects, HVAC designers, electrical designers, 340 Facilities managers etc. The following design output information may need to be provided to 341 these other parties to ensure correct accommodations for the AV rack(s): 342

a) Space planning requirements for AV racks – rack sizes and required clearances 343

b) Power requirements – supply capacity, types and connections 344

c) Structural requirements – rack weight(s), supporting plinths, wall strengthening (for 345 wall mounted rack(s)) 346

d) HVAC – Heat load, airflow direction, direct ducted connection details, operating 347 temperature and humidity ranges 348

e) Network requirements 349

f) Acoustics – anticipated noise level of AV rack (where installed in a sensitive 350 environment or requiring acoustic treatment by others) 351

352



353

7 RACK DESIGN VERIFICATION 354

Verification of the standard shall consist of ensuring all design inputs have been identified and 355 taken into account in the design process, and that all necessary design outputs have been 356 produced. Any items determined as not being required shall be noted as such on the checklist. 357

A design verification checklist is provided in Annex D. The checklist is provided in two parts 358 – design inputs and design outputs. The design inputs checklist shall be completed prior 359 undertaking the rack design. The design outputs checklist shall be completed at the end of 360 the design process. The process is summarized in the following flowchart: 361

362

363

Figure 10 Design Verification Process 364

The rack designer shall sign and date the verification checklists to confirm completion prior to 365 releasing the information for rack build. 366

367



ANNEX A – DESIGN INPUTS GUIDANCE (INFORMATIVE)

The following information is intended as additional guidance for some sections under design inputs.

A.1 Space Planning (Input)

Size and Quantity is determined by three equations based on volume, size of equipment and usable space within the location.

a) Total equipment height (including manufacturer-required ventilation space) + redundancy / height within the rack location = Rack units x quantity

b) Deepest depth of equipment + 20%? = Rack depth c) Rack quantity / width within rack location = Usable rack width available



A.2 Environmental (Inputs)

Thermal

Converting Watts to BTUs

There is a worldwide trend among standard-setting organizations to move all power and cooling capacity measurements to a common standard, the Watt., the following conversions are provided to assist the reader:

Given a value in Multiply by To get

BTU per hour 0.293 Watts

Watts 3.41 BTU per hour

Tons 3,530 Watts

Watts 0.000283 Tons

The worst-case assumption is amplifiers, although they can consume lots of power, are driving this most of the energy to loudspeakers that are installed outside of the 19" rack. For example, an amplifier efficiency of 70% means that 30% of the consumed amplifier energy is converted into heat in the amplifier. The other 70% of energy is converted into sound by the loudspeaker(s) and heat in the loudspeaker(s), and heat by the sound being absorbed by the area it is installed in.

This can have a major impact on the dimensioning of air-conditioning for 19" rack installations where significant amplifier power is used.

The table below is intended to provide information for HVAC to balance systems for thermal load.

Table for Calculations

Device Power consumption (max) Effective heat production

Any non-amplifier device #1 ….W = same as max W

Any non-amplifier device #2 ….W = same as max W

Any non-amplifier device #n ….W = same as max W

Amplifier #1 ….W = 30% of max W

Amplifier #2 ….W = 30% of max W

Amplifier #n ….W = 30% of max W

Totals SUM (…..) W = SUM (…) W

Acoustics (Input)

Noise Sensitivity Examples

19” racks are typically populated with equipment that is equipped with fans which emit audible noise.



Noise Criterion (NC) and Noise Rating (NR) curves depict the allowable noise levels in areas that have a predetermined use.

Referring to the table and relevant curves, where NR curves are commonly used throughout Europe and NC curves are commonly used throughout the USA; Any 19" rack should not produce sound pressure levels that exceed the curve that applies to the area in which the 19" rack is positioned.

The bold curves are NC & NR values that apply to the majority of areas where AV 19" racks are likely to be installed in domestic or non-server room like installs. (NC 20-35, NR 20-40)

When an install is not able to meet the required NR or NC curve, specific counter measures need to be taken to meet that specific curve (measurement with a calibrated NC/NR testing tool). These counter measures could apply to a specific frequency domain if the rack is only exceeding the noise level at a specific frequency of the applied NC/NR curve, or the countermeasures apply to the entire installation by acoustically isolating the 19" rack from the intended area of use.

Type of Room - Space Type - Application

Noise Rating

Recommended NC Level

Equivalent Sound Level

Curve (NR)

NC Curve dB(A)

Recording Studios, Concert and recital halls 25 15-20 25-30

TV Broadcast studies 25 15-25 25-35

Legitimate theaters 25 20-25 30-65

Private Homes, rural and suburban 30 20-30 30-38

Assembly Halls, Private Homes, urban, Conference rooms, Private rooms, Operating rooms, Lecture and classrooms 30

25-30 35-40

House of worship, Halls, lobbies, Private Office, Wards, Corridors, Movie motion picture theaters 30-35

30-35 40-45

Courtrooms 35 30-40 40-50

Laboratories, Public areas, Libraries, Open-plan classrooms, Open-plan offices 45-50

35-40 45-50

Business machines/computers, Restaurants, Service and Support Areas 45

40-45 50-55

Sport Coliseums 45-55 55-65

Factories 60-70 40-65 50-75



ApplicationType of Room - Space Type - Application

Noise Rating

Curve (NR)

Concert halls, broadcasting and recording studios, churches 25

Private dwellings, hospitals, theatres, cinemas, conference rooms 30

Libraries, museums, court rooms, schools, hospitals operating theatres and wards, flats, hotels, executive offices 35

Halls, corridors, cloakrooms, restaurants, night clubs, offices, shops 40

Department stores, supermarkets, canteens, general offices 45

Typing pools, offices with business machines 50

Light engineering works 60

Foundries and heavy engineering works 70



ANNEX B – DESIGN OUTPUT GUIDANCE (INFORMATIVE)

The following information is intended as additional guidance for some sections under design outputs.

B.1 Weight Distribution

Where the rack is to be installed in a location with fixings to prevent movement of the rack, no attention is required to the distribution of weight within the rack, although maintaining a low center of gravity is preferred.

Where the rack is to be installed in a location without fixings, or in a mobile situation, the AV equipment shall be loaded to maintain a low center of gravity to reduce the risk of toppling. AV equipment weight shall be distributed such that no less than half the total AV equipment weight is contained within the bottom third of the rack height.

B.2 Cabling

Mains voltage power cables should be bundled separately from signal cables. The table below illustrates accepted industry practices for minimum distances for signal and power cable separation. For specific industry requirements and guidance in cable spacing and layouts, please see ANSI-TIA-569 (current revision).



Table 1 Recommended Signal Separation

RECOMMENDED MINIMUM SEPARATION BETWEEN CABLES

Signal Type

Common Level(s)

Audio Micro-Phone Level

Audio Line Level

Video Cable

Data Twisted

Pair Cable

RF Coax Cable

Speaker Cable

AC Power Cable

Audio Micro- Phone Level

-60 dBV (0.001 volt) to -40 dBV (0.010 volt)

No Spacing Required

Separate Bundles

Separate Bundles

100 mm (≈4 in) minimum




Audio Line Level

0 dBV (1.000 volt)

Separate Bundles

No Spacing Required

Separate Bundles

Separate Bundles




Video Cable

0.8 volts Separate Bundles

Separate Bundles

No Spacing Required

Separate Bundles




Data Twisted Pair Cable

max 125 VDC


Separate Bundles

Separate Bundles

No Spacing Required

Separate Bundles

Separate Bundles


RF Coax Cable

0 dBmv to 50 dBmv




Separate Bundles

No Spacing Required

Separate Bundles


Speaker Cable

1 watt to 1,000 watts, max 100 VRMS




Separate Bundles

Separate Bundles

No Spacing Required


AC Power Cable

120/240 volts 50/60 Hz







No Spacing Required

B.3 Thermal Management

B.3.1 Airflow Management

The external, ambient air temperature must be capable of maintaining a safe operating temperature during time of use.

The minimum ambient air temperature shall be defined by the equipment with the highest recommended minimum operating temperature.

Maximum consistent internal operating temperature of the rack shall be the maximum operating temperature of the lowest rated piece of equipment or 30° C (85° F), whichever is lower.

In equipment with front-to-rear, bottom-to-top or no airflow, the rack airflow shall be front-to-rear and/or bottom-to-top to prevent mixed convections.

In equipment with rear-to-front airflow, rack airflow shall be from top to bottom with no passive venting in the upper portion of the rack.



Airflow (both intake and exhaust) shall not be blocked. Racks shall not be placed in positions where obstructions may compromise the intake or outtake of airflow to achieve the stated criteria.

The following aspects of airflow shall be considered during the design process and specified as part of the design criteria:

Generation of airflow: The inclusion of fans and blowers in the system for maintaining the minimum or maximum operating temperature. Fans and blowers can be used for cooling the entire rack or localized for individual components.

Uninterrupted airflow: Cables and non-rack mount (am I blocking airflow?) equipment shall be managed in a manner that will not prevent airflow of vents or fans. (See Section X for more info on cable management.)

Figure 11 Airflow Generation

Illustrates fan placement management for top mounted fans and front or rear mounted fans.



In AV equipment with front-to-rear, bottom-to-top or no airflow, the rack airflow shall be front-to-rear and/or bottom-to-top to prevent mixed convections.

In AV equipment with rear-to-front airflow, rack airflow shall be from top to bottom with no passive venting in the upper portion of the rack.

Accommodations shall be made to evacuate hot air out of the upper 20% or within the top 3 or 4 RUs of the rack to ensure cooling of all AV equipment within the rack. Rack airflow exhaust shall be greater than or equal to airflow intake.

B.3.1.2 Fan Types

The difference between axial and radial fans.

Axial fans: Pro's & Con's

Pro's

Dimension Large volume displacement of air

Con's

High turbulence High noise level Meant for low-pressure systems

Radial fans Pro's & Con's:

Pro's

Low noise Stable air flow/little turbulence Meant for over-pressure systems Energy efficient Can realize a high static pressure

Con's

Weight Dimensions

B.3.1.3 Fan and Vent locations – Actively Cooled Racks Only

The figure below illustrates fan and vent placement criteria for top mounted fans and front or rear mounted fans. This is for active cooling only.



[Graphic to be inserted] [Graphic to be inserted]

Vent Placement Fan Placement

# of RU Top Mounted Fan Front or Rear Mounted Fan

44 - 38 Avoid venting in the upper 15% (6-7 RU) Locate Fan in the upper 10% (4-5 RU)

37 - 25 Avoid venting in the upper 15% (5-6 RU) Locate Fan in the upper 10% (3-4 RU)

24 - Less Avoid venting in the upper 15% (4-5 RU) Locate Fan in the upper 10% (1-2 RU)

Figure 12 Fan Location Guideline Chart (adapted from Middle Atlantic graphic)

B.3.1.4 Temperature Probe Criteria

If thermostatic control is incorporated in the active cooling system, temperature probe(s) shall be located per the design criteria. If a design criterion is not available, place the temperature probe(s) within the upper 20%, within the top 3 or 4 RUs of the rack.

NOTE: Generally, the intake air temperature is measured at the positions from 30 mm to 50 mm away from the outline of the equipment to avoid the influence of heat radiation. At the air intake opening, if the temperature is not considered as homogeneous because the opening is so wide, several positions (3 to 5) should be defined as reference temperature positions, and the average temperature should be taken as the intake air temperature." from IEC page 7

More information about thermal management can be found in IEC/TS 62610-2:2011, Mechanical Structures for Electronic Equipment-Thermal Management for Cabinets in accordance with IEC 60297 and IEC 60917 series.

B.3.1.5 Vent/Blank Panel Criteria (Output)

Front-rail rack spaces shall utilize vent panels below equipment that generates excessive heat to promote proper cooling in active and passive cooling environments.

Vents shall be blocked, where necessary, to promote desired airflow and prevent hot spots.

When vent panels are not used, front rail rack spaces shall utilize solid blank panels to aid in air flow in active and passive cooling environments.

B.3.1.6 Vent/ Blank panels location

Brush panels should be used when connection is required on the front of the equipment.

B.3.1.7 Direct vent connections (Output)

Thermal Direct Venting is the dispersion of heat by means of structured air ducts connected to the 19” rack(s)/cabinet(s).

The ducts can feed cool air via the bottom of the 19” rack(s)/cabinet(s) and/or extract hot air via the top/rear of the 19” rack(s)/cabinet(s).

Ducting can be done using rigid and/or flexible air ducts.

Considerations for air ducts should involve;

Noise “transport” (distribution) to areas with higher acoustic restrictions (e.g. lower NC/NR ratings)



Fire/smoke spreading (venting) via airducts

B.4 Security

Fixing/fastening section

The method of fastening shall be suitable for the device and able to ensure the longevity of the method for mounting. Any fasteners shall be arranged to minimize the intrusion to adjacent rack spaces (see below).

Figure 13: Secure shelf mounting – front view showing fasteners coming from below (bottom image)

A fixing/fastening method using cable ties is acceptable where a mechanical fixing/fastening is impractical.

Courtesy of Middle Atlantic Products

Figure 14: Non-rack shelf mounting – two examples



Figure 15: Security Flow Diagram



ANNEX C SAMPLE DOCUMENTATION (INFORMATIVE)

C.1 Rack Design Equipment List and Summary Design Information



C.2 Rack Design Verification Checklist – Design Inputs

Item Description Constraint Input

Collected Notes

6.1 Regulatory/Client Requirements

Regulatory Requirements

Mandatory Certifications

Client Requirements

Optional Certifications

6.2 System Design

6.2.1 Equipment List

6.2.2 System Design Documentation

Head load information (on equipment list)

Power Requirement (on equipment list)

6.2.3 Other design information

6.3 Electrical

6.3.1 Available power supplies - rating/capacity

6.3.1 Available power supplies - quantity

6.3.1 Available power supply connection type

6.3.2 Earthing (grounding)/Bonding requirements

6.3.2 UPS Requirements

6.3.2 Surge protection requirements

6.4 Space Planning

Physical space at rack location

Site logistics constraints

Accessibility requirements - Disabled users

Accessibility requirements - service access

6.5 Environmental

6.5.1 Ambient temperature of rack location

6.5.1 Relative humidity of rack location

6.5.1 Rack location: controlled environment or not

6.5.2 Airflow Criteria

6.5.3 Noise sensitivity in rack location

6.5.4 Vibration and impact resistance

6.6 Security

Requirements for theft protection

Requirements for tamper protection

Security of rack location

Other security requirements

I certify that I have collected all design inputs required in accordance with AVIXA standard F502.02.

Signature Date



C.3 Rack Design Verification Checklist – Design Outputs

Item Description Provided Notes

7.1 Rack Definition

7.1.1 Type

7.1.2 Size

7.1.3 Quantity

7.1.4 Front elevation

7.1.4 Side elevation

7.1.6 Labelling requirements - racks

7.1.6 Labelling requirements - equipment

7.1.6 Labelling requirements - cabling

7.1.5 Non-rack mountable equipment mounting details

7.1.7 Optional components required

7.2 Thermal Management

Fan locations

Fan types/specifications

Vent/blank panel locations

Direct vent connection details

Defined maximum and minimum temperature range

Defined maximum and minimum RH range

7.3 Cabling

7.3.1 Location and type of cable management for internal cabling

7.3.2 Inter-rack cabling details

7.3.3 External cabling connection details

7.4 Electrical

7.4.1 Power supply feeds

7.4.1 Total load

7.4.1 Power supply input details - quantity

7.4.1 Power supply input details - capacity

7.4.1 Power supply input details - connection details

7.4.1 Power supply input details - cable type and length

7.4.1 UPS requirements of supply

7.4.2 Internal Power Distribution

7.4.2 Type of power distribution units - incl spare capacity

7.4.2 Quantity of distribution units

7.4.2 Unit/outlet/fuse labelling

7.4.2 Sub-distribution arrangements and mounting details

7.4.2 Allocation of distribution outlets to equipment

7.4.2 Surge protection devices

7.4.2 Internal UPS devices and wiring

7.4.3 Earthing/Bonding

7.4.3 Rack connection to earth/ground

7.4.3 Rack internal bonding



Item Description Provided Notes

7.4.3 Clean earth requirements

7.4.3 Specific signal earthing requirements

7.4.3 Static discharge prevention - additional bonding

7.4.4 DC Power Distribution

7.4.4 Quantity and type of DC power supplies

7.4.4 Mounting arrangements

7.4.4 Distribution/wiring arrangements

7.5 Security

Rack door locks

Rack side panels

Security screws

Equipment covers

Access control logging

7.6 Vibration and impact resistance

Rack fixings

Equipment fixings

Shock Absorption

7.7 Outputs for other designers

Space planning requirements

Power requirements

Structural requirements

HVAC requirements

Network requirements

Acoustic impact

I certify that I have conducted the rack design in accordance with AVIXA standard F502.02

Signature Date

f502.02:201x rack design for audiovisual (av) systems ... · 10 this standard covers the...

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