Compared with other kinds shredder, wood is relatively easy to tear, therefore, in the case of tell operation, load also increases, in wood industry, wood material is relatively is also different, therefore, will produce in line with the fluctuations, so when the switch to a different screen, for wood shredder load has a great influence. The motor capacity shall be 40 kilowatts when using a sieve with a diameter of 1.2mm. The motor capacity shall be 30 kilowatts when the screen size is 2 mm in diameter. When replacing the screen with a diameter of 3 mm, the motor capacity should be 22 kw, otherwise it will cause certain waste. There is a way to detect whether the wood shredder is overloaded or not. 1 directly use the contact gauge to indicate the material position within the cavity, that is, to know its load. 2. Use belt scale to weigh the conveying capacity of the belt conveyor. 3. The cycle load of closed circuit system is obtained by calculating crushing. The electric current in the motor circuit of the wood grinder is tested. The current in the mill is controlled at about 85% of the rated current. In multistage crush, generally only detection control granularity of the final product of the last paragraph of mill load, the crusher is usually in a closed loop system, its into the shoes including once upon a time a crush to quantity and cyclic load.