Annex I (informative) — Worked examples

Three products taken from first sketch to claim, to show how the clauses fit together, and five cases wired as 6.1 and 6.3 ask. The figures are illustrative. Each product example has a claim file in data/examples/ that eis claim accepts.

I.1 A module: a two-channel video mixer

It dissipates at most 12 V × 0.12 A + 12 V × 0.06 A = 2.2 W (Annex H).

I.2 A case: two rows with a built-in supply

A desktop case with two 104 HP rows, each 55 mm deep behind the panel; a built-in supply rated 4.0 A on +12 V, 2.0 A on −12 V, and 2.0 A on +5 V; and a built-in bus board with 28 headers and a 1.5 A per-header limit.

Whoever fills a case then budgets each row (9.1). row_budget_two_row.yaml does so for a separate example instrument, not the case above: two 84 HP rows, each with its own bus board and supply.

I.3 A video row: one video sync, one DC rail

Every coaxial shell, and the DC rail's −V, is the modules' 0 V (V75-002, GND-001), so the video sync, the picture, and the power share one 0 V. With the DC adapter floating and one earth bond at the case supply, there is no ground loop to show as hum bars (6.3).

I.4 Power distribution: five cases wired

Every conductor of row wiring in five cases, with its gauge and length, its resistance and drop, and the rule it meets. The resistances are the row wiring table's figures (6.1): stranded copper at 1.05 times the solid figure, plus 0.25 mΩ for each crimp and its bolted joint. Every ring terminal sits on an M4 terminal under a lock washer (PWR-005). The tables are generated from data/distribution_examples.json, and the generator refuses an example that breaks a rule.

One row from a DC adapter

A 3U, 84 HP desktop case in wood with anodized rails and steel M3 strips. A 12 V, 5 A desktop adapter plugs into a DC-DIN4 case DC entry panel at the left end of the row; a 48 W-class supply (2.6 A on +12 V, 1.0 A on −12 V, 1.0 A on +5 V) sits behind the row beside the entry; one bus board runs the row, its inlet terminals at mid-row.

The DC entry panel bonds 0 V to its panel through a 0 Ω link and carries the M4 CHASSIS stud; the case is wood and the rails anodized, so the chassis is the steel strips and whatever panels are bare under their screw heads, and no strap is needed (6.3). The adapter floats.

• One gauge for the whole case: 16 AWG, 1.5 mm² silicone, with red, blue, yellow, and black insulation for +12 V, −12 V, +5 V, and 0 V, and a 22 to 16 AWG ring terminal at every end.
• The 0 V conductor to the bus board carries the three rails' return, 3.6 A at most, and is the same gauge as the rail conductors beside it (PWR-007).
• Every module hangs on a power ribbon of at most 400 mm (BUS-015); the row wiring ends at the bus board.

Two rows from one supply

A 6U, 104 HP case in powder-coated aluminum with bare pads where the rails meet its sides, so the sides, rails, and strips are one chassis (GND-005). A DC-DIN4 case DC entry at the left feeds a 100 W-class supply (6.0 A on +12 V, 2.5 A on −12 V, 2.0 A on +5 V, 112 W out, about 11 A in at 85 % efficiency) mounted between the rows at the left end; each row has its own bus board with its inlet at mid-row, 250 mm from the supply for the upper row and 400 mm for the lower.

The tie is the DC entry panel's CHASSIS stud. A strap from it to the nearest bare pad on the case side bonds the metalwork; the supply's 0 V is not bonded to the case anywhere else, and the supply publishes that.

• The lower board's conductors are 14 AWG because of their length: 16 AWG over 400 mm would be over the 5 mΩ limit, as the table's alternative column shows.
• Each supply output terminal carries two ring terminals, one per board (6.1 recommends at most two); the +12 V terminal carries 6.0 A, within a 15 A terminal.
• The two boards hang on one supply, so ASM-009 does not require the link, but the two returns drop differently under load; the 12 AWG link holds the rows' references together for the cost of 180 mm of wire.

Four rows from two supplies

A 12U, 104 HP case, four rows, two 100 W-class supplies, one DC-MF8 case DC entry rated 28 A at the left feeding both supplies in parallel, about 11 A each. Supply 1 sits between rows 1 and 2 and feeds their boards; supply 2 between rows 3 and 4 and feeds theirs. Each board's inlet is at mid-row, 250 mm from its supply.

One tie, at the DC entry: its CHASSIS stud, strapped to the case side. Both supplies publish their 0 V as floating from the case. Row wiring returns run as two stars, one per supply; the links between the boards hold the four rows at one reference (ASM-009).

• The −12 V and +5 V conductors of each board are left out of the table; they follow the +12 V ones at 16 AWG and 250 mm.
• The DC entry's +12 V and 0 V terminals each carry two ring terminals, one lead per supply, and 22 A in all, within a 30 A terminal and the entry's 28 A; a 15 A terminal would need one lead per stud, which is why a high-current entry carries two studs per pole.
• Boards 2 and 3 each take their return and two links on 0 V, three rings: a bus board's second M4 0 V position, or a 0 V strip with a bar (BUS-021), is where the third goes.
• A chain of three links satisfies ASM-009 here, since every board reaches a board of the other supply through them; a fourth link, board 1 to board 4, would make it a grid.
• Terminals with more than two ring terminals: b2.0V, b3.0V; a second M4 position or a 0 V strip takes the third (6.1, BUS-021).

A rack frame with an AC inlet

A zinc-plated steel 19-inch rack frame, 3U, 84 HP, with an AC inlet on its rear panel and a linear bus supply (2.0 A on +12 V, 2.0 A on −12 V, 1.0 A on +5 V) on the rear panel too, 350 mm from the bus board's inlet at mid-row. The frame's plated steel bonds at every bolt.

The chassis is bonded to protective earth at the AC inlet, under the safety standard the supply is built to; 0 V meets the chassis at the supply's earth terminal, which the supply publishes (GND-003), on a strap to the frame. The DC side has no case DC entry, so there is no second tie.

• 2 A on +12 V would allow 18 AWG by current, but 350 mm of 18 AWG is 8.2 mΩ and 16 AWG 5.3 mΩ; the length, not the current, sets 14 AWG here. Shorter leads, a supply nearer the inlet, would do the same with 16 AWG.
• The 0 V conductor carries 3.0 A at most, +12 V and +5 V returning together against −12 V's 2.0 A.

Two cases, each with its supply

Two desktop cases of the first example side by side, each with its own adapter, DC entry, supply, and bus board, patched together. Each case's bus board carries a second M4 0 V terminal for the link.

Each case has its own tie at its DC entry; the adapters float, so the two ties make no loop. Each case has its own supply, so EIS recommends a 0 V link between the two bus boards (6.3): 10 AWG or heavier, as short as the cases allow, at most 2 mΩ where it can be. ASM-009's 2 mΩ binds inside one enclosure; three or more cases link as a grid.

• A 400 mm link on 10 AWG measures 1.9 mΩ, inside the 2 mΩ EIS recommends between cases; 12 AWG would reach only 270 mm, and past about 440 mm even 10 AWG cannot hold it, which is why the figure binds only inside a case. Hinton Instruments' ZeroVolt links between cases measure under 2 mΩ on heavy cable and high-current connectors.
• If the two cases shared one adapter through a case DC entry with two outlets, they would be one system with one tie; the supplies would still be two, so the link would still be wanted.