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Rack Power Insights
Short, sourced engineering notes on rack power — how to pick between metered, switched and outlet-metered PDUs, what UL 62368-1 changed for buyers, and what it takes to actually deliver ±1% billing-grade metering. Written by AmpRack Engineering, the factory that builds the metering boards itself.
Latest articles
Metered vs Switched vs Outlet-Metered PDU: How to Choose
Input metering, per-outlet relays and per-outlet kWh solve three different problems. A decision table, five filter questions and factory-direct price bands to match the tier to the rack.
Read the guide →
UL 62368-1 Explained: Why Your PDU Certificate Matters
UL 60950-1 was formally withdrawn on 2020-12-20. What the hazard-based replacement means for rack PDU buyers — and a seven-point checklist for verifying any supplier's certificate.
Read the explainer →
What ±1% Billing-Grade Metering Actually Means
Billing-grade is a precision claim, not a slogan. IEC 62053-21 class 1, per-unit calibration benches and 15-minute kWh freeze values — how ±1% is achieved and how colocations invoice with it.
Read the deep dive →Coming next in this series
The three launch articles cover the buying decisions we get asked about most in RFQs. The next four go one level deeper into the specs those decisions rest on — each one written against the same rule: every number traced to a standard, a measurement or a factory record. They follow the same reading order as our selection guides, so you can move from theory to a plug chart without leaving the site.
- Single-phase vs three-phase rack feeds: choosing between 16A, 32A and 63A inputs without stranding capacityPlanned
- C13, C19 and locking outlets: planning socket mixes for 8-48 outlets per rackPlanned
- 0U vertical vs 1U horizontal mounting: airflow, cable bends and PDU length trade-offsPlanned
- Sequencing and surge tolerance: powering up racks of sensitive equipment without tripping the upstream breakerPlanned
Need the hardware, not just the reading?
Every article here maps to a product line we build and test in-house. Send your input, outlet count and quantity — an engineer replies with a datasheet and FOB quote within 48 hours.
