Schools have a control switch above the general enough to write the ground is very clear at a glance to understand the following I talk about the care of the projector is a set of light, machine, electricity technology in one of the high-tech products, in daily use need to be carefully cared for. Special note: Do not cut off or unplug the power cord immediately after the projector has been used and turned off. As the projector is equipped with an automatic protection function, after the projector is turned off, its internal fan will still run automatically to reduce the temperature of the bulb to a certain extent, after which the fan will automatically stop cooling, so as to prevent damage to the core equipment of the bulb. If you cut off the power at this point, the fan will stop working and the internal heat will not be able to dissipate, resulting in shorter lamp life or damage to the projector.