Everyone has seen those cheap LED testers found all over the web at low prices. But how accurate are they? They’re not capable of testing RGB LEDs either, and certainly can’t measure the forward voltage drop. Well, check out this Multifunction LED Tester kit from Tindie seller LEDsales. It is very well-designed and absolutely packed with features!
It can test LEDs at a range of currents from 1 up to 40mA, using metal film resistors for good long-term stability. It also can test both common anode and common cathode RGB LEDs, selectable with a flick of a switch. As an added bonus, it can even test Superflux LEDs (the 4-pin LEDs often known as Piranhas).
The voltmeter on the front will show the battery voltage when no LEDs are connected, but when testing an LED it will show the forward voltage drop (Vf) of the LED! This is a very useful feature and can help you pick out slightly damaged or mis-matched LEDs. The illuminated button in the centre of the panel is used for brief testing, or you can choose to flip one of the three switches to constantly power one of the test banks.
This is not a precision tester, but as you can see in the included chart the measured values are within a fairly good tolerance. Only the red LEDs tend to be a bit on the high side. But for day to day measurements and binning LEDs, it’s an excellent tool! The included documentation is extremely well-written and easy to read, and it’s all through-hole soldering with large pads so even a beginner should be able to assemble the kit. If you work with LEDs often, pick one up and check your LEDs!
