Most of the time it will be static charge however I did have a funny story having this actually live when touched. Back in the day, we had some old Westinghouse escalators that didn't have any handrail entry switches. Then the regs changed and these had to be fitted. The repairs crew came and installed them then left. About a year later, after the handrail had started to stretch, and started to rub on the conduit supplying the switches with the 125v dc. Of course, it wore away the conduit and insulation on the wiring, and hence made the carbon in the handrail become active. Everyone that got to the top of the thing got a zap!! Funny times!!