5.2 Modules
A module fills HP in a row: a front panel, the boards behind it, and the parts on them. It takes power from the row's bus board through its power entry and screws to the rails of an enclosure.
A module shall be 1U or 3U high (PANEL-001); the panel height, the mounting holes, and the board clearance follow that choice. Its width is any positive whole number of HP (PANEL-002). A module shall publish its width in HP and how far it extends behind the panel's back face (PANEL-003), so that a buyer can check it against a row's published width and depth.
| A module's | Clause |
|---|---|
| Panel height, width, thickness, holes, patch jacks | 5.2.1 Front panels |
| Board clearance and depth | 5.2.2 Boards |
| Power entries and published current | 6.1 Power architecture |
| Power header and draw | 6.4 The bus |
| 0 V and protective earth | 6.3 Grounding and 0 V |
| Port list, signal classes, patch safety | 7 Signals |
Fitting a module into a row, with the current check that comes first, is in Assembling a system.
Tolerances
A dimension of clauses 5.2 and 5.3 shall hold within the tolerance the register states for its requirement, and a dimension with no tolerance stated is a limit (PANEL-013). The tolerances are in data/requirements.json and tabulated here:
| ID | Figure | Tolerance |
|---|---|---|
| RACK-001 | One HP shall be 5.08 mm. | exact: the grid value |
| RACK-002 | One rack unit shall be 44.45 mm. | exact: the grid value |
| PANEL-002 | An N HP panel shall be no wider than N × 5.08 mm, where N is a positive whole number. | ceiling; −0.3 mm recommended |
| PANEL-004 | A front panel shall be no more than 2.0 mm thick. | ceiling |
| PANEL-005 | A patch jack shall be a 3.5 mm mono (TS) socket. | none: a connector type |
| PANEL-006 | A 3U front panel shall be 128.5 mm high. | ±0.2 mm |
| PANEL-007 | A 1U front panel shall be 39.65 mm high. | ±0.2 mm |
| PANEL-008 | Mounting holes shall be 3.0 mm in from the top and bottom panel edges. | ±0.1 mm |
| PANEL-009 | The mounting-hole span, on the panel and between the inserts of a row's two rails, shall be 122.5 mm at 3U and 33.65 mm at 1U. | ±0.1 mm |
| PANEL-010 | Mounting holes shall be drilled Ø3.2 mm, or slotted 3.2 mm wide and no longer than 5.5 mm along the rail, centered on the hole position. | +0.1 / −0 mm on the 3.2 mm width |
| PANEL-011 | Each mounting hole shall be a whole number of HP plus 2.54 mm from the panel's nominal left edge. | ±0.1 mm |
| PANEL-012 | A board shall stay at least 9.25 mm clear of the top and bottom panel edges, and a rail shall cover no more than 9.25 mm of the panel face at each edge. | minimum and maximum |
| PANEL-013 | A dimension of clauses 5.2 and 5.3 shall hold within the tolerance the register states for its requirement; a dimension with no tolerance stated is a limit. | the policy itself |
| RAIL-001 | The holes in a rail insert shall be 5.08 mm apart. | ±0.05 mm per pitch; ±0.1 mm over any ten holes |
| RAIL-002 | A rail for an N HP row shall give at least N × 5.08 mm of mounting length. | minimum |
| RAIL-004 | An insert shall be at least 1.5 mm thick, three thread pitches. | minimum |
| RAIL-006 | A mounting screw's thread pitch shall be 0.5 mm. | ISO 965-1 class 6g on the screw, 6H in the insert |
| RAIL-007 | A mounting screw's major diameter shall be 3.0 mm. | ISO 965-1 class 6g on the screw, 6H in the insert |
| RAIL-008 | The screw shall engage at least three full threads through a 2.0 mm panel. | minimum |
| RAIL-009 | The mounting-screw length L shall satisfy 2.0 mm + seat + 1.5 mm ≤ L ≤ 1.6 mm + D, with seat and D measured behind the rail's mounting face, and the throat in front of the insert shall clear 3.0 mm. | a window: both bounds are limits |
| RAIL-010 | The mounting-screw head shall be at most 7.0 mm across. | maximum |