Commissioning: where powered-on becomes AI-ready
A liquid-cooled hall can be powered on, pass a walk-through and still not be ready to carry a training run. The gap is a set of acceptance criteria that were agreed before the work and tested against, gate by gate.
Definition
Commissioning and acceptance criteria (liquid-cooling commissioning · 调试与验收准则) are the tests and pass/fail thresholds agreed in writing before a liquid-cooling system is built, then checked at four gates: factory release, before the loop is filled, before compute is energised, and before handover. A criterion agreed after the test only describes what happened; one agreed before the work is a specification.
Before release from the factory
- Pressure and leak test of every skid, manifold and CDU as shipped, with serials
- Cleanliness class of wetted surfaces, verified by sample, not by statement
- Material certificates for elastomers and wetted metals against the named fluid
- Factory run of controls: pump staging, valve travel, sensor calibration
Before the loop is filled
- Weld map complete; every field weld inspected and logged
- Flush to cleanliness class; passivation confirmed separately from flushing
- All fill, drain, vent and sample ports capped, tagged and logged
- Pressure test of the assembled loop at the agreed factor and hold time
Before compute is energised
- Fluid chemistry at fill matches specification: inhibitor, pH, conductivity, biocide
- Flow balance across racks within tolerance, recorded per branch
- CDU approach measured at available load and extrapolated with the method stated
- Compute-and-liquid isolation sequence executed and timed, not just reviewed
Before handover
- Baselines recorded: temperatures, pressures, flows, power, at a stated load
- Metering boundary drawn on a single-line diagram and signed
- Every disturbance since fill closed out in the connection log
- Turnover package assembled in the ten-boundary structure and indexed
Three principles behind the gates
Criteria are written before the work. An acceptance criterion agreed after the test is a description of what happened. One agreed before is a specification. We put the numbers in the contract, not in the closeout report.
A boundary disturbed is a boundary re-tested. The loop does not pass once. Every quick disconnect mated after the pressure test, every port opened for a sample, resets that boundary's status until it is logged again.
The boundary of every number is stated. Load level, ambient, metering point and period go into the record with the reading. A figure without them cannot be compared to anything, including to itself a year later.
Questions this page answers
When is a liquid-cooled hall ready to carry an AI training run?
When the acceptance criteria agreed before the work have been tested and recorded at all four gates: factory release, before fill, before compute is energised, and before handover. Powered-on and walked-through is not the same as AI-ready; the difference is a set of numbers in the contract and the records that show they were met. Commissioning as a service →
What are the four commissioning gates for liquid cooling?
Gate 1, before release from the factory: pressure and leak tests per skid and CDU, cleanliness class verified by sample, material certificates against the named fluid. Gate 2, before fill: weld map complete, flush and passivation confirmed separately, all ports capped and logged. Gate 3, before compute is energised: fluid chemistry at fill, flow balance per branch, CDU approach measured. Gate 4, before handover: baselines recorded at a stated load and the turnover package assembled. The turnover package the gates produce →
Who writes the acceptance criteria, and when?
They are written into the contract before the work, by the party accountable for the whole thermal path, and reviewed by the operator and the commissioning agent. A criterion agreed after a test only describes what happened; one agreed before is a specification that a supplier can be held to. The whole thermal path →