by ericmark »
Fri Oct 20, 2017 6:45 pm
I find the G5.3 extra low voltage lamps a problem, there are so many types, the ones I have are clearly marked 50 Hz so need a toroidal transformer not electronic transformer and not a driver. Others at marked DC 10 - 30 volt designed to run off batteries or some other ripple free device.
I have not found any MR16 replacements which require a driver, every one I have found has the driver built in, however I have found regulated DC power supplies labelled drivers. Although a drive is a device which regulates the current supplied to LED lamps, it seems some label anything to do with LED's drivers.
Although a power supply may be DC that does not mean it is ripple free, to regulate power the typical method is to use switch mode or pulse width modulated, this means it switches on and off many times a minute and gives an average voltage of 12 volt, this is all well and good if the lamp it feeds has a simple resistor to control current, but with the better quality lamp they have chips which also uses switch mode to regulate current,
If you have two switch mode regulators one feeding the other then the second one is being switched off all the time so can't stabilise. It may seem odd but cheap inefficient LED packages giving 70 lumen per watt are often better than the expensive giving 100 lumen per watt because the expensive have built in switch mode regulation.
It is unlikely you can see 50 Hz flicker, birds can see it, but not humans, since a toroidal transformer is expensive I now use GU10 low voltage (230 volt) everywhere but bathroom, and the G5.3 are clearly marked 50 Hz so I know are matched to transformer used.