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19 Inch Rack Panel Calculator

Panel height, width and mounting slot positions to EIA-310. Change the rack units and everything updates. Nothing is sent anywhere.

Nominal is 19 in = 482.6 mm. Machining slightly under avoids binding in a tight cabinet.

Result

Panel height
Panel width
Thickness
Rack space used
Clearance per panel
Slot centres from panel centreline
Slot centres, vertical
Slot size7.0 x 11.0 mm, vertical
Clearance hole equivalent7.14 mm (0.281 in)

Slot centres are given from the panel centreline in both axes, because dimensioning from an edge accumulates the panel width tolerance into the hole position.

Drawing note

The clearances the standard does not mention

These are what actually stop a correct panel from fitting.

  • Handle envelopeRack handles project forward and sideways. Check they clear the rail and the cabinet door.
  • Screw headA screw head plus a cup washer needs about 3 mm of flat panel around the slot.
  • Chassis offsetThe panel is wider than the chassis behind it. The chassis body has to clear rails that project inward.
  • Proud featuresA lip, a bent edge or a proud fastener eats the 0.4 mm inter-panel clearance and binds a full rack.
  • AirflowA solid panel in front of a warm chassis blocks front to back airflow.

Questions

The full treatment is in the rack panel guide.

Why is the panel height not a whole number of rack units?

A rack unit is 44.45 mm of vertical space, but the panel is made slightly shorter so that a full rack of equipment does not bind. The standard formula is h = 44.45n minus 0.79 mm, which leaves roughly 0.4 mm of clearance above and below each panel.

Should I machine the panel to exactly 482.6 mm wide?

Machine it slightly under, typically 482.0 to 482.6 mm. A panel at exact nominal will bind in a cabinet whose own opening is at the low end of its tolerance. A little under is invisible and always fits.

Round holes or slots?

Slots, roughly 7 mm wide by 10 to 12 mm tall, centred on the standard position. Rail hole spacing varies within the standard and older threaded rails vary more, so the installer needs a couple of millimetres of vertical movement.

Are these numbers a substitute for the standard?

No. They are the figures from EIA-310 that a panel designer uses, reproduced so you can work quickly. For a product going into someone else’s cabinet, check the cabinet manufacturer’s own drawing as well.

Need the panel made?

Send the drawing. We match it with up to 3 shops that machine and finish rack panels, and reply within 24 business hours.