Failures are rarely caused by wrong wiring — it is the seal orientation, cable size, torque and cable entry direction. Six things that go wrong on site, and how to do them right.

Which standard governs industrial plugs and sockets? What IEC 60309 covers, what the colours mean, how to read the two IP digits and why the clock position has to match.

The same plug can be terminated in different ways: screw, ErgoCONTACT, TwinCONTACT or screwless insulation displacement. What each suits, and how much time it saves.

Stiff insertion, loose fit or a hot plug are often down to the contact sleeve, which sets contact pressure, insertion force and service life. X-CONTACT versus the classic MENNEKES sleeve, materials and plating, and how to choose by application.

An IP67 enclosure with the wrong gland has no protection at all. Selection by IEC 60423 thread and cable diameter, with our full M12–M63 table and the blanking plugs for unused entries.

Hand lamps, inspection lighting and damp locations use 20–50V connectors that look different from ordinary industrial sockets: no earth contact, and two keyways for mistake-proofing. The IEC 60449 definitions and the low-voltage models we stock.

SCHUKO is the German earthed socket (CEE 7/3): 16A 230V, 2P+E, no earth pin — earthing is through the side clips. How it differs from industrial CEE, the national variants, and the models we stock.