Colocation & Edge
Multi-tenant racks live and die by metering accuracy.
Billing-Grade Metering
Multi-tenant colocation billing starts at the receptacle. A billing-grade PDU must report kWh and current within +/-1% so operators can defend tenant invoices and reconcile upstream utility meters.
Specify C13 and C19 receptacles for the right load envelope: IEC C13 is rated 10 A, IEC C19 is rated 16 A, and IEC C21 is rated 16 A in hot conditions. Meters should retain per-outlet and per-branch readings for audit trails and remote dispute resolution.
Colocation Requirement Map
| Requirement | What to specify |
|---|---|
| Tenant energy billing | Billing-grade metered PDU with +/-1% accuracy |
| High-density cabinet feed | 11-22 kW switched PDU, 24x C13 + 24x C19 HDOT |
| GPU tenant architecture | 48V ORv3 architecture replacing 12V tray power |
| PDU and PSU safety | UL 62368-1 compliance |
| Busway distribution | IEC 61439-6 type-tested, UL 857 busway up to 6300 A |
| Power supply efficiency | 80 PLUS Titanium: 96% efficiency at half load |
| Battery backup | UL 1973 and UL 9540A for BBU batteries, UN38.3 shipping |
| Remote ops | Outlet-level switching and per-branch current monitoring |
| Transformer risk | Global lead times reached 160 weeks; include in site schedule |
| Tariff exposure | US tariffs on Chinese dry-type transformers hit 46.6%, some lines +125% |
Remote Ops Wins
- Cut smart-hands dispatch with outlet-level power cycling on 11-22 kW switched PDUs
- Bill tenants on +/-1% metered kWh instead of flat-rate estimates
- Isolate a locked GPU tray remotely without affecting other tenants on the same 0U unit
- Preconfigure per-cage power policies for new deployments, including per-receptacle current limits
Space Economics of 0U PDUs
Renting by the rack U changes the arithmetic. A vertical 0U PDU preserves usable rack space while still delivering dense C13 and C19 options for multi-tenant deployments.
Use 0U units with 24x C13 and 24x C19 HDOT to cover high-density cabinets without forcing tenants into adapters or power strips that consume rack units.
- IEC C13 rated 10 A
- IEC C19 rated 16 A
- IEC C21 rated 16 A hot condition
- 11-22 kW switched cabinet feed
- Billing-grade metering +/-1%
Operator View
If the kWh meter drifts, tenant trust disappears. Billing-grade PDU metering is not optional for us.” — a European colocation operator
Why +/-1% metering decides tenant trust
Colocation contracts bill by the amp. At 0.8 dollars per kWh, a metering error of 2 percent on a 10 kW rack is roughly 1,400 dollars per year per rack — enough to erase the margin on the deal. Billing-grade PDUs hold +/-1% at input and outlet level, which is what auditors expect before a multi-tenant deployment signs off.
Edge site checklist
- 0U vertical PDUs to save cabinet space for compute
- outlet-level switching for remote reboots without truck rolls
- environmental probes paired with the PDU network
- one spare PDU per 40 racks deployed on site
- firmware pre-configured before shipping to cut commissioning time
