Correct operation method of sound system switch
The general audio system is composed of many independent audio units, such as: tuner, deck, equalizer, LD machine or VCD machine and AV power amplifier. These units need to be inserted into the 220V AC power plug board. In order to save trouble, some people turn off the power of the plug when they are turned off; when the power is turned on, they are all powered on as soon as the plug is turned on. Although this method saves trouble, there are hidden dangers. Because this operation will generate surge current and anti-peak voltage, these two shocks will often damage the audio equipment. The damage of some equipment is mostly generated at the moment of turning on or off, but not in the normal working state.
Surge current: An audio equipment is composed of components such as resistance, capacitance, inductance, transformer and so on. They are in a cold state before turning on. When starting up, its resistance is small, so the instantaneous current is very large, which is 2.5-3.5 times the normal working current. This current is called inrush current, which can cause damage to the circuit.
Anti-peak voltage: Inductive components, transformers and other units have a characteristic that when a voltage is added or a voltage is removed from the circuit, the unit will generate a back electromotive force to prevent this voltage from changing. Then when a voltage is applied to the inductive component at startup, it generates a back electromotive force to prevent the establishment of this voltage, but the power supply voltage has a continuous source of energy, so this back electromotive force only acts as a voltage damping effect and has little effect on the circuit. However, the situation is different when shutting down. When shutting down, a back electromotive force is generated in the circuit without any obstruction. This voltage is the reverse peak voltage, which is 9 times the normal voltage. Although its current is small, the voltage is very high, causing an impact on the device. Therefore, the surge current and anti-peak voltage of each audio unit act on the audio equipment at the same time to cause a large impact, which is easy to cause damage to the equipment. Therefore, each audio unit * is turned on and off sequentially one by one. The correct boot sequence is to boot in the direction of the sound source signal flow: turn on the deck, CD player, LD player or VCD player, tuner, equalizer in turn, * turn on the power amplifier.
The correct shutdown sequence is to turn off the amplifier first, and then turn off other devices.
At present, in order to facilitate the use of foreign countries, there is a delay type power supply latch board. * The group socket is a direct switch socket; the second group socket, when the machine of this way is turned on, can delay the power supply for 1s (second); the third group socket, when the machine of this way is turned on, it can be delayed It only takes 2s (seconds) to turn on the power; the fourth group of sockets, when this machine is turned on, it can be delayed for 3s before turning on the power. It is similar to this when shutting down, and also shuts off the power in different periods of time. In this way, the phenomenon that the surge current and the anti-peak voltage act on all equipment at the same time and damage the audio equipment is prevented.