Norlys Koster 1915GR LED post-top luminaire 17.5 W 3000 K, ø50 mm spigot, graphite RAL 7016

Koster 1915GR is a post-top luminaire: a dome shade with a small knob on top, hung from a side arm with a mounting sleeve. The housing is cast aluminium powder-coated in graphite, RAL 7016, and the lower diffuser is clear, textured UV-stabilised polycarbonate. Only the luminaire is supplied — the pole is bought separately.

Mounting on the pole

The sleeve fits a 50 mm pole spigot and slides on to a depth of 80 mm, so check the diameter of the pole top before buying. It connects with a 3.7 m H05VV-F 3G1 cable run inside the pole to a junction box. The luminaire weighs 3.07 kg and its side area is 0.01 m² — the figure used when sizing a pole for wind load. The maker's photometry is given for a 2.5 m mounting height.

It is a protection class I fitting, so it needs an earth conductor. The inrush current is 3.01 A for 32.66 µs, which matters when several lanterns share one breaker.

What light it gives

The integrated 17.5 W Philips Fortimo module produces 1950 lm, and 1568 lm leaves the fitting — the level of main lighting rather than mere orientation light. 3000 K is a warm white. The light is directed downwards; ULOR is 0% and the BUG rating B1-U1-G2, so it does not shine into the sky. The luminaire is not dimmable.

The LED module is replaced by a professional service; the maker lists it as a spare part, as it does a diffuser service kit.

Where it fits

IP54 allows outdoor use, and the IK10 impact rating is the top of that scale, useful in public places. The maker describes the design as classic; in the catalogue it is assigned to gardens, parks and the surroundings of hotels and restaurants. The Koster range also offers versions for a 60 mm spigot and fittings with two shades.