{
 "description": "The power interfaces of EIS chapter 6: one row per interface, read by tools/power_interfaces.py into the table of clause 6.1 and the ripple limits of clause 6.2, by the power-interfaces card, and by tools/claim.py and tools/row_budget.py for the rails a claim file or a row budget states at each interface.",
 "interfaces": [
  {
   "id": "PWR-BUS",
   "name": "The bus",
   "rails": "+12 V, −12 V; +5 V optional",
   "rail_keys": [
    {
     "key": "plus12",
     "label": "+12 V",
     "required": true
    },
    {
     "key": "minus12",
     "label": "−12 V",
     "required": true
    },
    {
     "key": "plus5",
     "label": "+5 V",
     "required": false
    }
   ],
   "made_by": "power supply",
   "distributed_by": "bus board and power ribbon",
   "entry": "power header, 2 × 5 or 2 × 8",
   "entry_connectors": [
    "BUS-IDC10",
    "BUS-IDC16"
   ],
   "outlets": "supply terminals, bus board headers",
   "outlet_limit_a": 1.5,
   "clauses": [
    "6.4",
    "6.5",
    "6.6"
   ],
   "ripple_limit_mvpp": 150,
   "ripple_note": "Most open-frame switching supplies meet it."
  },
  {
   "id": "PWR-DC12",
   "name": "12 V DC",
   "rails": "12 V: one +V and −V pair",
   "rail_keys": [
    {
     "key": "v12",
     "label": "12 V",
     "required": true
    }
   ],
   "made_by": "external adapter, outside EIS, or a power supply with PWR-DC12 outlets (6.2)",
   "distributed_by": "PWR-DC12 outlets of a bus board, a module, or a supply, and DC cables",
   "entry": "DC entry, any variant of 8.1",
   "entry_connectors": "data/dc_12.json variants and entry_inlets",
   "outlets": "DC-BAR21 jacks and DC-VH2 headers to modules (DC-009); M4 row wiring terminals to a supply or a bus board (PWR-005), on any product with PWR-DC12 outlets",
   "outlet_limit_a": null,
   "clauses": [
    "8.1"
   ],
   "ripple_limit_mvpp": null,
   "ripple_note": "No limit: each product filters or regulates its DC rail (8.1); a supply publishes the figure (SUP-001)."
  }
 ],
 "row_wiring": {
  "description": "Clause 6.1, row wiring: the discrete conductors between a power supply, bus boards, a DC entry, and PWR-DC12 outlets (PWR-005 to PWR-008), on M4 ring terminals, at most 5 mΩ each (PWR-007, after Hinton Instruments).",
  "target_mohm": 5,
  "termination_mohm": 0.25,
  "termination_note": "each crimp and its bolted joint, allowed at both ends of a conductor",
  "link_mohm": 2,
  "link_note": "a 0 V link between bus boards fed by different supplies (ASM-009), or between cases (6.3)",
  "strand_factor": 1.05,
  "strand_note": "stranded, tinned copper against the solid annealed copper of ASTM B258 at 20 °C",
  "max_a": 25,
  "terminals": [
   {
    "form": "threaded standoff, vertical, through-hole",
    "example": "Keystone 7795 (snap-in, M4 internal thread)",
    "rated": "15 A"
   },
   {
    "form": "threaded standoff, right angle, through-hole",
    "example": "Keystone 7794 (press-fit) or 7769 (solder)",
    "rated": "15 A"
   },
   {
    "form": "press-fit or THR power terminal",
    "example": "Würth Elektronik REDCUBE with M4 internal thread, such as WP-BUFU",
    "rated": "the maker's rating, far above a row"
   },
   {
    "form": "screw and nut, or a stud, through a bus bar or a chassis",
    "example": "M4 screw, ISO 7045 or ISO 4762, with an ISO 4032 nut",
    "rated": "the bar's section"
   }
  ],
  "conductors": [
   {
    "awg": 18,
    "mm2": 0.82,
    "metric_mm2": 1.0,
    "solid_mohm_per_m": 20.95,
    "up_to_a": 3,
    "ring": "red, 22 to 16 AWG"
   },
   {
    "awg": 16,
    "mm2": 1.31,
    "metric_mm2": 1.5,
    "solid_mohm_per_m": 13.17,
    "up_to_a": 5,
    "ring": "red, 22 to 16 AWG, or blue, 16 to 14 AWG"
   },
   {
    "awg": 14,
    "mm2": 2.08,
    "metric_mm2": 2.5,
    "solid_mohm_per_m": 8.282,
    "up_to_a": 8,
    "ring": "blue, 16 to 14 AWG"
   },
   {
    "awg": 12,
    "mm2": 3.31,
    "metric_mm2": 4.0,
    "solid_mohm_per_m": 5.211,
    "up_to_a": 15,
    "ring": "yellow, 12 to 10 AWG"
   },
   {
    "awg": 10,
    "mm2": 5.26,
    "metric_mm2": 6.0,
    "solid_mohm_per_m": 3.277,
    "up_to_a": 25,
    "ring": "yellow, 12 to 10 AWG"
   }
  ],
  "ring": "insulated or heat-shrink ring terminal for the conductor, 4.3 mm hole (M4 or #8), tin-plated copper, crimped with the ratchet tool its maker names",
  "lock": "a split or toothed lock washer under the screw head or nut, or a screw with a captive one",
  "wire": "stranded tinned copper, 105 °C PVC (UL 1015 at 600 V, UL 1569 at 300 V) or silicone (UL 3135), silicone where the wire flexes",
  "colors": "red +12 V, blue −12 V, black 0 V, no color named for +5 V (6.1); green-and-yellow only for an earth bond",
  "earth_bond_min_awg": 14,
  "link": "12 AWG or heavier, or a braided bonding strap or bus bar of the same resistance; at most 2 mΩ terminal to terminal, after Hinton Instruments' ZeroVolt link"
 },
 "zero_v_bar": {
  "description": "Clause 6.5, the 0 V strip and bus bar of BUS-021: what EIS recommends for the strip, the bar, and the clamping.",
  "strip_min_width_mm": 6,
  "strip_note": "a band of the outer-layer 0 V plane, bare of solder mask, finished as the pads are, with plated holes at the mounting-hole positions, M4 at the ends and one more M4 near the middle of a long board",
  "strip_2oz_mohm_per_m": 41,
  "strip_2oz_note": "the bare strip alone: 70 µm (2 oz) copper 6 mm wide",
  "bar_target_mohm": 0.5,
  "copper_nohm_m": 17.24,
  "copper_note": "annealed copper, C110 or C101, at 20 °C; brass is about four times the resistance and is not recommended",
  "bars": [
   {
    "width_mm": 6,
    "thick_mm": 2
   },
   {
    "width_mm": 6,
    "thick_mm": 3
   },
   {
    "width_mm": 6.35,
    "thick_mm": 3.18,
    "stock": "1/4 × 1/8 in"
   },
   {
    "width_mm": 6,
    "thick_mm": 4
   },
   {
    "width_mm": 6,
    "thick_mm": 5
   }
  ],
  "clamp": "a screw with a lock washer at every strip hole, torqued as the board's mounting screws are; the bar no wider than the strip",
  "joint_mohm": 0.1,
  "joint_note": "a clean bar clamped at every hole measures under 0.1 mΩ from the bar to the plane"
 }
}