Author Topic: 50v Low Voltage lamp to LED converter  (Read 2348 times)

Offline BillTodd

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50v Low Voltage lamp to LED converter
« on: December 05, 2014, 08:28:48 AM »
If you have a low voltage (50vac) lamp on your machine you'll probably know it is a PITA to find a 50v bulb when you need one.

This simple converter will allow you to use the now common GU10 LED bulb in place of the 50v incandescent lamp. It'll work fine with LED lamps of upto 10watts (if you need more watts you'll need to use 100u @100v low ESR caps)

It uses a simple voltage doubler circuit (two 4007 diodes and two 47u@100v caps and a 2R2 fusable resister) to double the 50vac to 128vdc which is enough to run the LED lamp (these lamps have a world-wide universal 90-240v ac/dc circuit inside (even the ones that say 220v on them), so are quite happy at this voltage).

I built the circuit into a B22 to GU10 adapter (these are available on ebay for a few quid) but if used in a working environment you should build it onto the lamp with B22 plug and encase it in heat-shrink to comply to LV health and safety standards.