I have produced what could well be the worlds most powerful caving and mining caplamp, capable of sustaining maximum output.  The first ran 5 X Cree Q5 XR-E emitters each at one amp plus. The next version had a Cree MCE quad die as the centre emitter to give a flood option. The last had a total output of 2400 lumens, this is the new XML version.

This lamp at maximum power produces in access of 3200 lumens as a beam, or a 'daylight mode' of about 2760 lumens.

This lamp has 4 X Cree  XM-L emitters, plus 6  Cree R5 XP-G emitters in an outer ring as bare emitters, it also has the emergency light as on the Trigon. The switch is modified so that it does not turn round and round like a normal Oldham switch, but through 360 degrees. Full anticlockwise is the normal "off" position, turning the switch clockwise reaches the first switching position which is 2 of the XM-Ls in form of a good beam.

SW1 Is exactly the same as the beams of the Trigon, there are Standard, High and Turbo modes gained by turning on an off. Standard is the same 168 lumens for a modest 1.6 watts draw on the battery, while turbo is the same 1600 lumens.

Noticeable is the fact that this lamp has a much broader beam than the Trigon, logical as the reflector borings are smaller.

SW2 Lights up 2 of the 4 XP-Gs at a current of 1.46 amps to produce about 920 lumens from the 2 which are connected in series.

 SW3 Brings on line the emergency light, exactly the same as the Trigon. This as I have said before is bright enough to get you out of anywhere and would burn for about 3 weeks on the 10 cell belt mount battery pack.

Turning back counter clockwise reaches SW2 again, but this time it brings on line all 6 bare XP-Gs to give a ‘daylight mode’ of about 2760 lumens.

Turning back to SW1 will bring all 4 XM-Ls on line to give an output of 3200 lumens.

 Now I have to say here that in the economy department the new lamp is vast improvement on the old. With the exception of the emergency light all the other emitters are series wired, and this together with good driver design means that the 3200 lumens maximum output is achieved for a battery draw of 37 watts, less than the old one took to generate 2400 lumens. The new one is also an inherently simpler lamp having been able to dispense with a certain amount of circuitry, although rather expensive to produce with its large array of powerful emitters.

Left shows the special switch modification that gives the 3rd position

The lamp has 5 totally independent lighting circuits from 3 switch positions, and 5 different LED configurations.

 The weight is about 400 grams which is double that of the standard unmodified Oldham; however it is not really noticeable, at least not to me.

 Full power mode has enormous throw, but also a reasonable amount of spill. I have tested the lamp and its output is sustainable, after about 5 minutes large amounts of heat are being pumped out by the thermal conductor.

The front extension is made up from high pressure PVC pipe couplings designed for operation up to 15 psi. The original Oldham bezel is solvent welded to the extension, and the hexagon nut is likewise solvent welded to the headset. The only entry is by the high pressure joint which is sealed with silicone. The seal can be broken but takes some force, it then being necessary to clean away the old silicone and make a new seal. The thermal conductor is 12mm diameter and passes down inside the lamp for a distance of 20mm where there is a flat machined into it where the LED module is firmly seated with a 4mm screw. The thermal unit is secured by a nut and silicone waterproof seal.

BATTERY PACKS

The lamp utilises either a 4 cell helmet mount battery pack or a 10 cell belt mount mount, both are quickly changeable so spares can be carried underground.

Above is the lamp fitted to the 10 cell belt mount battery. ( Early model lamp)

Here are some test results.

Above is the lamp with 2 of the 4 XM-Ls on Turbo mode, this is 1600 lumens, not full power.

Above is full power, the whole 3200 lumens. The shots all all straight off the camera, no messing with them except for turning them upright, and taken in an underground quarry in a central Wales lead mine.

USEFULNESS?

Accepting that the usefulness of a lamp of this power is somewhat questionable, the main useful purpose is for photography and video. Below are 2 pictures taken in Carrs Level Nenthead without any flash and with the camera set to automatic setting. I would not have thought that this could be done at one time.

Below is a photo of Ystrad Einion waterwheel taken on daylight mode, Fujifilm S9600, ASA 100 F5.6 at 13 seconds. No other lighting.

TABLE OF FIGURES, PRICE ETC TO BE UPDATED AFTER PROLONGED TESTING OF NEW LAMP

UPDATE

So far this new lamp is working out very well but it will be some time before one can be offered for sale as it needs a of testing and evaluation.

August 2011 Update

Oh Dear, its looking rather like the battleships that were being launched in the late 19th Century, obsolete on the day they were launched. Just as I think I have the job sorted, something new comes along. The mission now is to produce a small lightweight lamp utilising the new thermal technology but with the output of the lamp described above, or even higher.

All I can say is "Watch this space"

Sorry.