The CDU Compatibility Table Has No Owner, So Closure Has No Recipient

The blocker register names a sender for the capacity curve and names two parties, jointly, for the fluid and materials table that would use it. It names no single recipient. One document would close the rating, and the blocker register names it precisely: a statement of the fluid the nameplate was calibrated on, together with a capacity curve over the four arguments the rating actually depends on [TARGET]. The register also names who owes it, which is the equipment supplier. What it does not name is anyone to receive it. The interface those arguments meet at is recorded in the same document as having no single responsible party, so the closure evidence exists in the plan with a sender and no addressee.

Matching the Two Supply Temperatures Is an Owner Decision

Each argument is registered separately and each is waiting on someone different [TARGET]: - primary-side inlet temperature, which follows from the heat-rejection route and is recorded as the hardest interface on the project; - secondary supply temperature, which the equipment supplier sets and the facility side cannot choose; - the secondary temperature difference, which is waiting on the cold plate's allowable band and its maximum return temperature; - the fluid, the one argument where the register states a consequence rather than a range.

That a rated capacity is a function of those four rather than a constant, and that the supplier package's own part-load representation is derived from the rating itself, are findings an earlier entry already carries; they are cited here and not reworked. The register's own addition is narrower. The compatibility table that would reconcile a summer primary supply temperature against a supplier's required secondary supply temperature has no single responsible party, and that absence is listed as an owner decision in its own right rather than as a technical gap.

Closing the fluid blocker needs three written things: a purchased-fluid property table against temperature; the supplier's allowed-fluid list and inhibitor; and a materials compatibility statement. The owner line is owner procurement plus supplier recognition. The allowed-fluid list is a Gate 1 branch; the rest of the blocker is Gate 2. Wrong inhibitor is recorded as the direct defence to a cold-plate corrosion claim. Fluid ledgers are the evidence a later claim would have to rest on: without sample records the owner in practice carries the whole cold-plate failure risk.

The Capacity Curve Has a Sender and No Addressee

An unassigned owner decision is not the same kind of open item as an unmeasured quantity, and the register keeps them in different tables for that reason. The four arguments close when somebody produces numbers. The interface closes when somebody is named, and nothing in the document names them, declines the role or records that the question was put. The document marks the same distinction in its own structure: technical blockers are listed with an owed party and a latest date, while this one sits in the table of decisions the owner has to make and carries neither. It is the only item in this set that no amount of supplier data can answer.

That matters because the closure evidence is addressed to a party who has to act on it. A capacity curve over four arguments is only useful to whoever is allowed to set the two supply temperatures against each other; with no such party, a curve arriving from the supplier lands on a table nobody maintains. The package's graphical evidence already shows what an unaddressed document looks like: the only curve supplied anywhere in the set is a flow-ratio against resistance-ratio plot with no equipment identification, no operating condition, no source points and no signature [TARGET].

A supplier review of a different packet records that the plate is not all one alloy: copper braze and mixed fittings sit on the same assembly, and the air-side description is copper tube with aluminium fin. Room-temperature viscosity in that packet does not cover a cold start. None of those rows names a single recipient either.

The hydraulic chapter's only mandatory suggestion on contract structure is that the two sides of the primary-to-secondary interface must not be promised by different parties with nobody responsible for the match. Compatibility sits in the set of items the principal design cannot close unilaterally. The responsibility matrix names the Engineer of Record on that row; the owner decision that would designate a single party for the match remains unassigned.

The Enquiry May Name Four Arguments, Not One Rating

The decision is what may be written into the enquiry package. Freezing a single rated capacity before the curve exists puts an unconditional number into a document that bidders price against, and the register's position is that the four arguments are the specification while the single figure is not. All three of its distribution-unit branch quantities are held on the same terms, and its own note on this branch is that a held quantity is not a purchase freeze, an enquiry issued or a selection made [TARGET]. The first two of those four arguments are the approach pair; specifying them would set the approach.

The register neither asserts a derate nor computes one. It asserts that the conditions under which the rating holds are enumerable and currently unstated, which is a weaker claim and a different one, and it makes that claim about a document set rather than about equipment.

Limits and open items

Confirmed: a held branch quantity is not a purchase freeze, an enquiry issued or a selection. [FACT]

Register figures: four arguments; one unaddressed compatibility table; one flow-ratio plot with no equipment identification. [TARGET]

Open: a named single party for the match of the two supply temperatures; the three written things that would close the fluid blocker; any of the three held branches selected. [HOLD]

Nothing here has been reviewed or sealed by an Engineer of Record. Nothing describes how any installed system behaved.

Name Who Must Read the Curve When It Arrives

Naming a single party responsible for the compatibility of the two supply temperatures does not produce the curve, shorten the wait for it or settle any of the four arguments; it decides who is obliged to read it when it arrives. The register has the question written down and no date against it.

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Source: K&K Data Service Inc., “The CDU Compatibility Table Has No Owner, So Closure Has No Recipient,” https://www.kkdatasvc.com/lab/hydraulic-calculation-detail/the-compatibility-table-has-no-owner-so-the-closure-document-has-no-recipient/.