How to Specify a Server Rack: RU, Depth, Load, Cable Entry and Cooling

A server rack spec­i­fi­ca­tion often gets reduced to "42RU, 800 deep, black". That's a start, but it leaves out most of what de­ter­mines whether the rack works on the day and for years after. Here's a fuller checklist, with notes on how Argent racks address each point.

Start with the equipment list

List every device: model, height in rack units, depth, weight, power draw and airflow direction. Add expected growth over the rack's life. Every­thing else follows from this list.

Height (RU)

One rack unit (RU) is 44.45mm, as defined by the IEC 60297 standard for 19-inch equipment. Add up your equipment and include space for patch panels, cable managers, blanking panels and growth. 25–30% spare is a common rule of thumb.

Argent's 50 Series security racks are available as wall-mount units in 6, 12 and 18RU, and as free­stand­ing racks from 18 to 46RU. The 40 Series open-frame rack is 45RU standard.

Depth and width

Measure your deepest device, then add space for cables and power at the rear. Argent 50 Series depths range from 700mm to 1200mm. Wider racks give room for vertical cable man­age­ment, which is es­pe­cial­ly useful in high-density patching.

Load

Total the equipment weight and add a margin. The Argent 50 Series is rated to 1200kg. Remember the floor has to carry the load too, par­tic­u­lar­ly on raised floors and upper storeys.

Doors and access

• Per­fo­rat­ed doors support front-to-back airflow.
• Solid or glazed doors suit dusty or visible locations.
• Door swing: check clearance in the room. Argent 50 Series doors open past 180°.
• Rear access: wall-mount cabinets can include swing frames, such as the C Class wall-mount cabinet.

Locks and security

Choose standard locks for general en­vi­ron­ments, com­bi­na­tion locks for con­trolled access, and SCEC-endorsed locking for security-clas­si­fied en­vi­ron­ments. The Argent 50 Series uses KABA X10 com­bi­na­tion locks for Class B, or Bi-Lock handles for Class C (details). For sensitive devices in shared racks, the patented V50 Data Vault adds a lockable enclosure inside any 19" rack.

Cable entry and man­age­ment

Decide whether cables enter from the top or bottom, how many there are and how they're protected. In SCEC racks, cable entries must be compliant, so you can't just drill holes. Argent provides options guides for SCEC cable entries, and has designed a baffle system giving 18 entry ports where needed (case study). For open frames, the 40 Series offers scalable cable manager ducts from 529 to 1,634cm².

Power

Plan PDUs for the total load with re­dun­dan­cy. Argent's in-post PDU mounts power within the rack post, freeing rack space for equipment. It's a popular feature in projects such as Sydney Trains.

Cooling

Match cooling to heat load. Options include per­fo­rat­ed doors, ther­mo­sta­t­i­cal­ly con­trolled fans and, for higher densities, hot or cold aisle con­tain­ment. Argent's article on hot aisle con­tain­ment explains the approach.

Configure it online

Argent now has six online con­fig­u­ra­tors, covering the 10, 25, 40 and 50 Series, the V50 Data Vault and the Com­mer­cial Data Cage. They're part of OPIE Man­u­fac­tur­ing Group's 45-con­fig­u­ra­tor platform. The con­fig­u­ra­tors only offer valid com­bi­na­tions, giving you a firm starting point fast. Start in the OPIE con­fig­u­ra­tor.

Fre­quent­ly asked questions

How much spare space should I leave in a rack? Many designers allow 25–30% spare RU for growth, plus space for cable man­age­ment and airflow.

Should I choose top or bottom cable entry? It depends on the room: overhead cable trays suit top entry, and raised floors suit bottom entry. Plan entries before ordering, es­pe­cial­ly for SCEC racks.

What's the dif­fer­ence between a 2-post and a 4-post rack? 2-post frames suit lighter patching and network equipment. 4-post frames support deeper, heavier equipment such as servers.

Can I change the con­fig­u­ra­tion after ordering? Talk to us as early as possible. Changes are easier before man­u­fac­tur­ing starts.

For anything unusual, such as dual-com­part­ment racks, custom entries, special colours or pre-loading, talk to Argent's engineers.