A Yablochkov candle consists of a sandwich of two long carbon blocks, approximately 6 by 12 millimetres in cross-section, separated by a block of inert material such as plaster of paris or kaolin. There is a small piece of fuse wire or carbon paste linking the two carbon blocks at the top end. The assembly is mounted vertically into a suitable insulated holder.
On application of the electric supply, the fuse wire 'blows' and strikes the arc. The arc then continues to burn, gradually consuming the carbon electrodes (and the intervening plaster) as it does so. The first candles were powered by a Gramme machine. 開始供電的那一瞬，引燃絲熔斷并點燃電弧。電弧持續(xù)燃燒，逐漸燒蝕碳棒（和中間的熟石膏），電燭早先時候由gramme直流電機供電。
Electrodes last about two hours or until the power is cut. A classic Yablochkov candle cannot be relit, since the fuse wire between the electrodes has been consumed. Later versions of the candle, however, included powdered metal in the inert separator. This would act as a new fuse wire, allowing a half-burnt candle to be restarted once extinguished.電極的壽命大約2小時，或者因斷電提前掛掉。早期的雅布洛奇科夫電燭不能重新點燃， 因為頂端的引燃絲已經(jīng)（在上一次點燃時）用掉了。后續(xù)的版本在中間的絕緣體中摻雜了金屬粉末，充當(dāng)了新的引燃絲，可以讓中途熄火的電燭重新啟用。
The advantage of the design over other carbon arc designs is that it removes the need for a mechanical regulator to maintain the appropriate distance between the carbon blocks to sustain the arc.與其他碳棒電弧（燈）設(shè)計相比，該設(shè)計的先進(jìn)之處是取消了用于調(diào)節(jié)碳棒間距以維持電弧的機械調(diào)節(jié)機構(gòu)。
Left: the Yablochkov (Jablochkoff) candle was the first product, it had two carbon rods side by side (see illustration) separated by a laster, it burned down from the top with the arc begin kept at the idea gap width. This was a way to get around the problem of feeding two carbon rods together in the regular lamp model. It was a simple operation to replace the rods when finished. The device produced an unsteady light that would range from dark purple to bright white. Sometimes it went out, which would lead to the entire series of lamps (up to six) going out. But it was a important step and the first commercially successful electric light.
