Oldham headlamp

Oldham is Denchi Group's brand of battery-powered mining and safety lamps, with roots going back to 1913. The lamps are used in mining, tunnelling, construction, quarries, defence and the emergency services. The current main model is the DL16, a conventional corded headlamp in which the headpiece is attached to the helmet and powered by a Li-ion battery. The system consists of the lamp, battery and microprocessor-controlled charger, and the manufacturer emphasises the lowest possible total cost of ownership.

The DL16 has a 3 W Rebel3 LED with a light output of 6 000 lux / 180 lumen. 90% of the light is concentrated in an 8° spot, while 10% is spread over 120°. A separate 20-lumen auxiliary LED serves as an emergency light with over 800 hours of burn time. The main light lasts 18 hours with a further 6 hours of emergency reserve, and the electronics keep the brightness constant throughout a normal shift; if the lamp is used beyond a full shift, the light fades gradually and noticeably. Charging time is 8–10 hours, and the battery is designed for over 1 200 charging cycles.

The lamp is built for easy maintenance: the battery and headpiece are maintenance-free, all spare parts are available, and the battery has protection against inrush current, overcharging, low voltage and temperature. Charging is via a standard keyhole connector on Oldham's microprocessor-controlled chargers; the manufacturer recommends charger type 204001 (2-channel) or 204002 (10-channel) for L16 and E16 batteries. The headpiece measures 67 x 67 x 70 mm, the battery 152 x 125 x 55 mm, and the complete system weighs 975 g with IP54 protection. Oldham's Li-ion batteries were introduced in 2007 and were among the first with ATEX, MSHA and ITACS approval; for explosive atmospheres there is the AE16 variant, which is certified for M1 mining applications with an ATEX M1-approved E16 battery.