北京市音响设备厂

Some people in order to save trouble, turn off the power supply when the switch off all off; when the boot is also a set of plug in all electricity. Although this method is difficult, but there is a hidden danger. Because such operations produce surge current and anti peak voltage, these two shocks often damage the sound equipment. The damage of some equipment is mostly in the moment of opening or closing the machine, and the well is not damaged in normal working condition.

浪涌电流：

Surge current:

开机时，其电阻阻值小，所以瞬间电流很大，是正常工作电流的2．5-3．5倍。这个电流被称为浪涌电流，其对电路可造成损害。

When starting the machine, the resistance value is small, so the instantaneous current is very large, and it is 2.5-3.5 times of the normal working current. The current is called surge current, which can cause damage to the circuit.

反峰电压：

Peak voltage:

当关机时，电路中产生一个反电动势没有任何的阻挡，这个电压就是反峰电压，它是正常电压的9倍。虽然它的电流很小，但是电压很高，对设备造成一个冲击。

When the machine is shut down, there is no barrier to a back EMF in the circuit, and this voltage is the anti peak voltage, which is 9 times the normal voltage. Although its current is very small, the voltage is very high, causing a shock to the equipment.

        所以，正确的开机顺序是按照音源信号流程的方向开机：依次打开卡座、CD机、LD机或VCD机、调谐器、均衡器，最后开启功率放大器。正确的关机顺序是先关掉功放，再关其他设备。

So the boot order is correct according to the audio signal boot process direction: in order to open the cassette, CD, LD or VCD, tuner, equalizer, finally open power amplifier. The correct shutdown sequence is to turn off the power amplifier first, and then close the other equipment.