When the circuit is short-circuit or seriously overloaded, the armature of the over-current release will pull in to make the free release mechanism act, and the main contact will disconnect the main circuit
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Miniature circuit breaker (MCB) is the most widely used terminal protection device in building electrical terminal distribution device
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When the circuit is under voltage, the armature of the under voltage release releases, which also makes the free release mechanism act
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After the main contact is closed, the free tripping mechanism locks the main contact in the closing position
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It is suggested that 1PN air switch or leakage protection function should be selected for the switch of lighting circuit, which is also unnecessary; 3
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It is used for short-circuit, overload and overvoltage protection of single-phase and three-phase below 125A, including single pole 1p, two pole 2p, three pole 3P and four pole 4P
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Now let’s talk about the working principle of the circuit breaker: the miniature circuit breaker is composed of operating mechanism, contact, protection device (various releases), arc extinguishing system, etc
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Once there is overload or short circuit on the zero line, the circuit breaker can not provide protection
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Well, just now we explained the working principle of circuit breaker
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1p circuit breaker: only one wire can be connected, usually the live wire, then the zero wire of your other wire can only be led out from the zero wire terminal block
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When the circuit is overloaded, the thermal element of the thermal release will generate heat and bend the bimetallic sheet to push the free release mechanism
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The width of 1p circuit breaker is 18mm, so 2p is 2 * 18 = 36mm
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So when do we use these circuit breakers separately? 1
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The port on 1p can only connect one wire, 1PN and 2p can connect two wires, and so on
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The main contact is manually operated or electrically closed
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1PN and 2p circuit breakers: since both circuit breakers can connect two wires, 1PN circuit breaker and 2p circuit breaker can control the zero wire and live wire at the same time to keep the on-off of zero live wire synchronized
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It is suggested that 2p leakage protection function should be selected for all the circuit switches of other sockets and the knowledge platform of water and electricity installation Protector, this is very necessary, the most time to choose 1p with leakage protection function of leakage protector;.
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The coil of the over-current release and the thermal element of the thermal release are connected in series with the main circuit, and the coil of the under voltage release is connected in parallel with the power supply
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It is said that P represents the pole, which in fact represents the number of wires
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First of all, let’s understand the meaning of 1p, 2p and the following P
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However, although 1PN circuit breaker is connected with zero live wire at the same time, it can only detect live wire, and the protection effect is the same as 1p circuit breaker
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Now it’s more popular that 1p circuit breaker can only control one wire of you, 2p circuit breaker can only control two wires of you, and so on
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In this way, we should all understand
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We must choose 2p air switch as the main switch, not with leakage protection function, which is neither necessary nor beneficial; 2
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What kind of problem will this lead to? 1p circuit breaker, because it is only connected to the live wire, can only detect the live wire
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So what is the position of P? Please look at the figure below
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Generally speaking, it is the space occupied
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P represents the pole
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So what’s the difference between unipolar 1p, bipolar 2p, triode 3P and quadrupole 4P? What are their respective functions? Today I will explain this knowledge to you
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2p circuit breaker can detect two wires at the same time and protect two wires 3P circuit breaker: 3P circuit breaker is used in pure three-phase circuit, and its principle is the same as 2p circuit breaker
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