Dim bulb tester - totally enclosed, with switchable cooling fan

[eblc1388]

I would like to share with a you a very useful gadget in testing and repairing. I made mine using three halogen lamps with rating of 75W, 150W and 300W. I choose halogen lamps as their size are small and still widely obtainable. However, it might be difficult to get the specific wattage required. They are mounted onto ceramic lamp holders because of the possible high temperature. The internal wirings are done using silicone cable. The whole circuit fitted inside a server power supply case as shown.

Using three separate switches, the combination of the lamps offer a wattage range from 75W to 525W with steps of 75W. An additional three-position switch is also added for switching an internal 12V fan or bypass the lamps all together.

If you are thinking of making one but have not yet committed to, at least gather all the lamps first when they are still easily available.
You can can also add an extra 500W lamp to the combination to get more wattage ranges.

[wizard69]

Cool, but how do you see the bulbs in operation?

[SeanB]

I would assume through the numerous cooling areas of the case, as only a bright lamp will provide visible light.