Datacenter

Related classes: Data_Hall · IT_Rack · Server · Rack_Power_Distribution_Unit · Uninterruptible_Power_Supply · Computer_Room_Air_Handler · Chiller · Rack_Environmental_Monitor

A data center is modelled with the same three building blocks as any other facility: Places for the spatial hierarchy, Things for the equipment and Points for what the equipment reports. This page lists the classes the ontology actually has for each layer and the relationships that tie them together. Where a concept has no dedicated class, it says so.

Spatial hierarchy

The containment chain is Site → Building → Floor → Room / Zone, linked with hasPart / isPartOf (both Place → Place).

Concept	Class	Notes
Data hall	Data_Hall	A subclass of Server_Room
Aisle, row	Aisle	A Zone. There is no Row, Hot_Aisle or Cold_Aisle class; use Aisle and the entity name
Operations	Network_Operations_Center, Data_Center_Operations_Room	Both Rooms
Staging	Data_Center_Staging_Room	Where IT equipment is configured before installation
Interconnect	Meet_Me_Room	A Telecom_Room, alongside Switch_Room and Distribution_Frame
Electrical rooms	Electrical_Room → Battery_Room, Generator_Room, Transformer_Room	Adopted from Brick
Underfloor supply	Underfloor_Air_Plenum	Modelled as HVAC equipment, not as a Place

A cage or tenant suite has no class of its own either: a plain Zone inside the Data_Hall, plus a serves edge from the equipment to the Data_Center_Tenant organization, covers it.

Racks and IT equipment

Two rack classes exist: IT_Rack (a Device) and ICT_Rack (an ICT_Equipment). IT_Rack is the one with a description and the one this guide uses; ICT_Rack is undocumented in the export.

What goes in the rack descends from Data_Center_IT_Equipment:

• Server → Rack_Server, Blade_Server, housed in a Blade_Chassis
• Storage_Array
• Computing_Accelerator → Graphics_Processing_Unit

Networking sits under Data_Network_Equipment: Ethernet_Switch, Network_Router, Network_Security_Equipment, Ethernet_Port, Wireless_Access_Point. A Rack_Environmental_Monitor is the sensor device that hosts a rack's environmental points.

Rack → server → GPU nesting uses Thing.hasPart / isPartOf. Every Thing has exactly one hasLocation → Place (the relationship is declared with minimum and maximum multiplicity 1), so a rack is located in its Aisle (or the Data_Hall), and the servers inside it are isPartOf the rack.

Power chain

From the utility to the outlet, in the order power flows, linked with feeds / isFedBy (Thing → Thing, Place or Collection):

1. Transformer and Switchgear → Circuit_Breaker, Main_Circuit_Breaker, Bus_Tie_Breaker
2. Generator with its Diesel_Fuel_Storage_Tank; Automatic_Transfer_Switch and Static_Transfer_Switch
3. Uninterruptible_Power_Supply with a Battery, Battery_Cabinet or Battery_Energy_Storage_System
4. Power_Distribution_Unit, Busway → Busway_Tap_Off_Box, Bus_Riser, Breaker_Panel
5. Rack_Power_Distribution_Unit → Intelligent_Rack_Power_Distribution_Unit, which feeds the servers

Metering uses Electrical_Meter and Building_Electrical_Meter. The chain can be grouped as an Electrical_System and watched by a Data_Center_Power_Monitoring_System.

Cooling

Air-side units overlap, all adopted from Brick: Computer_Room_Air_Handler (CRAH), Computer_Room_Air_Conditioning → Standby_CRAC, and CRAC (no description). Pick one per site and stay with it. Plant: Chiller and its subclasses, Cooling_Tower, Dry_Cooler, Airside_Economizer and Waterside_Economizer. Liquid cooling: Coolant_Distribution_Unit and Rear_Door_Heat_Exchanger. Cooling equipment feeds the Data_Hall (a Place) or a rack directly.

Points

Where	Point classes
Rack environment	Rack_Air_Flow_Sensor, Rack_Differential_Pressure_Sensor, Air_Temperature_Sensor, Relative_Humidity_Sensor. No rack-inlet or outlet temperature class exists; name the entity
Hall environment	Zone_Air_Temperature_Sensor, Underfloor_Air_Plenum_Static_Pressure_Sensor, Water_Leak_Alarm
Power	Active_Power_Sensor, Active_Energy_Sensor, Branch_Circuit_Current_Sensor, Branch_Circuit_Power_Sensor, Voltage_Sensor, Power_Factor_Sensor, Frequency_Sensor
Backup power	Battery_Voltage_Sensor, Battery_Level_Sensor, Emergency_Generator_Status
Liquid cooling	Supply_Coolant_Temperature_Sensor, Return_Coolant_Temperature_Sensor, Coolant_Flow_Sensor
IT load	CPU_Utilization_Status, GPU_Utilization_Status, GPU_Temperature_Sensor, Cooling_Capacity_Utilization_Status

A point attaches to the entity it describes with hasPoint / isPointOf (a Thing, Place or Collection) and to the device producing the reading with hosts / isHostedBy (a Thing). A rack inlet temperature is therefore isPointOf the rack and isHostedBy the rack environmental monitor.

Example

Site "Campus North"
└─ Building "DC1"                                hasPart ↓
   └─ Floor "Level 1"
      ├─ Data_Hall "Hall A"
      │  └─ Aisle "Row 01"                        isPartOf Hall A
      │     └─ IT_Rack "A-01-07"                  hasLocation → Row 01
      │        ├─ Rack_Server "srv-0142"          isPartOf rack
      │        │  └─ Graphics_Processing_Unit "gpu-0"
      │        ├─ Rack_Power_Distribution_Unit "pdu-A0107"   feeds → srv-0142
      │        │  └─ Active_Power_Sensor           isPointOf pdu-A0107
      │        └─ Rack_Environmental_Monitor "env-A0107"
      │           └─ Air_Temperature_Sensor "inlet" isPointOf rack, isHostedBy env-A0107
      ├─ Computer_Room_Air_Handler "CRAH-3"        feeds → Hall A
      ├─ Electrical_Room "ER-1"
      │  ├─ Uninterruptible_Power_Supply "UPS-A"   feeds → pdu-A0107
      │  └─ Switchgear "SWG-1"                     feeds → UPS-A
      └─ Generator_Room "GR-1"
         └─ Generator "GEN-1"                      feeds → SWG-1

The systems view groups the same entities: Data_Center_Infrastructure_Management_System, Data_Center_Environmental_Monitoring_System and Water_Leak_Detection_System are System collections whose hasPart members are the Things and Points above.