CU Phosco P111

Lantern acquired in August 2019.

This P111 was one of a number removed from the Bath Street area of Ilkeston Town Centre in 2019, following their replacement with Urbis 'Abbey' heritage LED post-tops; the P111s being installed in late 2014 / early 2015 as replacements for Thorn Celest 55 Watt PL-L lanterns, which were, themselves, temporary replacements for failed D.W. Windsor 'Victoria' lanterns. LED P111s saw very limited use in Derbyshire, with the Ilkeston examples being about the largest quantity seen.

Whilst the P111 is, more commonly, seen with a black canopy and base, the Ilkeston examples had their metalwork finished in maroon (the actual colour is RAL 3005, Wine Red), in order to match the appearance of other street furniture, and indeed, the lighting columns themselves.


Unlike my 35 Watt SOX lantern, this version of the P111 has its light source (in this case, nine LEDs) arranged on a downward-facing plate in the top of the lantern. The use of LEDs requires the lantern to be orientated correctly on the column, in order for the correct beam distribution to be achieved. Therefore, the lantern is facing to the right in this view, with the pre-wired supply cable being attached to the front support rod. An 'Across Road' indicator is affixed to the front of the LED plate.


A factory-fitted Zodion SS12A miniature photocell rated at 35 Lux is situated on the underside of the lantern's base section. Owing to the placement of the photocell, the switching accuracy will be reduced; only with the cell pointing skywards would it switch at the correct light levels, but because of the P111's design, with a curved canopy, this limits the suitable locations for the photocell to be placed.


The identification label is situated on the inside of the base casting; this informs that the LEDs are driven at a 450 mA current, and that the lantern was manufactured in January 2015. Despite being IP 54 rated, the lantern interior was quite dirty, with numerous signs of insect ingress.


Unscrewing the finial and then lifting the canopy reveals the lantern's internal wiring, along with the LED driver.


The Philips 'Xitanium' driver is positioned centrally above a heat sink that is intended to assist in dissipating the heat generated by the LED array. Although this driver is set to run the LEDs at full output at all times when activated, it can be programmed to dim using the DALI (Digital Addressable Lighting Interface) system.


The lantern was fitted to a dedicated post-top stand on Wednesday, 30th December 2020.

A plug was connected to the pre-wired flexible cable, and the supply switched on...unfortunately, the lantern decided that it didn't wish to operate correctly any longer, with the the LED array activating at full brightness, then dimming immediately, then switching off, on a repeating cycle. This video demonstrates the fault. (Typically, the lantern had worked perfectly when tested many months earlier, and had been placed in dry, indoor storage since then.)

I had thought that the driver was defective, and so purchased a replacement. The flashing continued with the new one connected, however, and so the original was unlikely to be the cause of the fault. Therefore, I turned my attention to the LED array itself. Carefully, the plastic cover over the circuit board was prised off. With this removed, a faint watermark was visible in the centre of the board, and a short section of the copper track had become exposed.

The mark was visible on the inside of the cover too, and shortly after this picture was taken, the lens covering the LED chip located the closest to the cable hole fell off of its own accord. I think that that says it all. The lantern was unceremoniously removed from the post-top stand straight after these pictures were taken and its place taken by the converted Philips XGS 103 instead, and worked far more reliably - there is no space in my Collection for duds!


Thorn Isaro Pro S | Philips XGS 103




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