When the LED light is turned off, it will be faintly lit. Is it a problem with the lamp?

In recent days, a number of customers have reported: Is there a problem with the lights in your home? I just installed it, turned off the switch, the light is still faint, and it has been lit all night, this is what happened! The electrician could not find out the reason.

In fact, this has nothing to do with the lamps, this is just a commonsense mistake made by careless electricians !

Why is it always lit after the power is cut off? Because the electrician is disconnecting the electric switch, the power-off switch is connected to the neutral line, not the live line. The electrician knows that the power-off switch must be powered off with a live wire, otherwise there is a danger of electric shock. However, the electricians invited by these customers actually turned off the power with the neutral line. After the power is cut off, the live wire continues to supply power to the LED drive power supply, which will cause the LED light to have a faint light after the switch is turned off.

For a qualified electrician, this is a common-sense mistake that should not be made. However, everyone knows that it is very simple for people to pick up the electrical switch. It can be done by picking it up, so the "singular" incident of the light after the power failure will happen repeatedly!

Another problem is: the dual control switch controls the LED light. Why does it flash after 6-7 seconds after the power is turned off?

Analysis of the cause: The dual control switch measures the lamp head voltage with the multimeter's AC file when it is off. It is found that 24V-68V AC is changing, and the 24V-68V AC change is between 1-7 seconds. AC power is exchanged. When the voltage exceeds 50V, the LED will flash, and when it reaches 68V, it will jump to 0V quickly, then immediately to 24V, and it will rise slowly after reaching 40V. Take off the LED load, and then measure the return line of the dual-control switch to find 120V AC. After analysis, it is a dual-control switch circuit. The wire is long and the high-potential line in the parallel phase line is still high after the power is cut off. This phenomenon does not occur when the incandescent lamp is connected. The current required for LEDs and the like is small, so the induction power is accumulated to a certain LED's turn-on voltage, and it is discharged, and the LED flashes.