- Light output: the light output of 1.5 watt LEDs is slightly higher than the 10 Watt halogen bulbs and significantly below those of 20 watts. The color temperature is a bit cooler than halogen, but still far away from cool white. A barely noticeable blue proportion is. The light distribution is evenly all around, but their design weaker longitudinally. I notice in the lamp over the kitchen table, which is thus less well lit than with comparably powerful G4 halogen lamps.
- Lifespan: Up to now half a year without problems and thus significantly longer than almost all G4 halogen bulbs used previously. Thus, it has been worth the investment. The temperature development is quite high. I have measured in a very thick and narrow version of glass up to 70 ° C with the infrared thermometer on the lamp. But there was as yet no discoloration or damage to the material and as I said, no failures.
- Security and energy supply: If you want to replace with these LEDs his old G4 halogen lamps it is imperative to replace the transformer by an AC / DC low-voltage transformer / driver with matching output and replace all halogen lamps with LEDs. It is restricted to change not only a terse light bulb. Who does not know how to do that, please leave in the interests of his own safety, steer clear of it and ask someone who is familiar with it.
Background: the lamps require mandatory 12V direct current (DC - direct current), as it says in the description and has always been. The normally installed G4 12V halogen transformers provide alternating current (AC - alternating current). The LED lamps operate temporarily with an existing alternating current transformer, as I have also tested, because they get along apparently some time with an AC half-wave with a peak of 12 V. But they during extended use, as reported also in many other places, flicker, turn out partly or completely or wegschmoren, is at the wrong power supply. This means danger to life and limb! This is the LEDs with an old and existing DC transformer partially not work because the need the old switching power supplies used a minimum load to jump. Ex. 5x LED with 1.5W = 7.5W, which is too little for a transformer with 10W minimum load. Which manage some by leaving a halogen bulb between the LEDs, the power consumption increased overall, but what I can not recommend it. Either replace everything and use a matching transformer or completely stay with halogen lamps, which also have their advantages.
Addendum of 12/15/2014:
The LED are now in use for a year and not burned. the lamps are daily at the 4h operational. There was a copy in a partial failure of two banks led to approximately 9 months - as measured by the almost monthly breakdown of the previously used halogen bulbs a huge difference. The silicone has become a bit dull in some lamps.
In the LED offered here it comes to seemingly monthly changing manufacturers and qualities. I bought the 1.5W LED on the make BestMall through the retailer Park Pai. This order also applies to my review. Meanwhile, I have also a few more copies with 3.5 watts of Fa. Sebson in use. They are really bright, have a much more uniform light color and yield, but cost many times over. I still stand by my assessment that giving me the power of the purchased here favorable 1.5W LEDs is very good for the price.