保护
protect
（1）缓冲托辊温度保护
(1) Buffer roller temperature protection
带式输送机滚筒与皮带摩擦使其温度超限时，紧贴滚筒安装的检测装置发出超温信号，接收机收到信号后，经3s 延时，使执行部分动作，切断电动机供电，输送机自动停转，起到温度保护作用。
When the belt conveyor drum rubs with the belt to make its temperature exceed the limit, the detection device installed close to the drum sends out the over-temperature signal. After receiving the signal, the receiver delays for 3 seconds to make the executive part act, cut off the power supply of the motor, and the conveyor stops automatically, thus playing the role of temperature protection.
（2）托辊组速度保护
(2) Speed protection of idler group
若输送机发生故障，如电动机烧毁、机械传动部分损坏、皮带或链子拉断、皮带打滑等，安装在输送机被动机件上的事故传感器SG中的磁控开关不能闭合或不能按正常速度闭合这时控制系统将按反时限特性经一定延时后，速度保护电路起作用，使执行部分动作，切断电动机供电，以避免事故扩大。
If the conveyor fails, such as motor burning, mechanical transmission damage, belt or chain breaking, belt slipping, etc., the magnetron switch installed in the accident sensor SG on the passive parts of the conveyor can not close or can not close at the normal speed, then the control system will be delayed according to the inverse time characteristic to ensure the speed. The protective circuit acts to make the executive part move and cut off the power supply of the motor so as to avoid the enlargement of the accident.
（3）缓冲托辊煤仓煤位保护
(3) Buffer roller coal bunker coal level protection
煤仓中设高低两个煤位电极，煤仓由于无空车不能放煤时，煤位将逐步升高，当煤位上升到高位电极时，煤位保护动作，从首台皮带输送机开始，各台输送机因机尾堆煤依次停车。
There are two high and low coal level electrodes in the coal bunker. When the coal level rises to the high level electrodes, the coal level protection action starts from the first belt conveyor, and each conveyor stops in turn because of the tail coal heap.