301130 PILZ 继电器 质保无忧，选择放心

产品详情

所谓“安全继电器”是由数个继电器与电路组合而成，为的是要能互补彼此的异常缺陷，达到正确且低误动作的继电器完整功能，使其失误和失效值愈低，安全因素则愈高，“安全继电器”并不是“没有故障的继电器”，而是发生故障时做出有规则的动作，它具有强制导向接点结构，万一发生接点熔结现象时也能确保安全，这一点同一般继电器完全不同。

安全继电器是一个安全回路中所必须的控制部分，它接受安全输入，通过内部回路的判断，确定性的输出开关信号到设备的控制回路里。简单地说，安全继电器都是双通道信号型，只有两个通道信号都正常时，安全继电器才能正常工作；在工作过程中，只要其中任一通道信号断开，安全继电器都会停止输出，直到两个通道信号都正常且复位后才能正常工作。

一、安全继电器工作原理

1、电磁式

电磁式继电器一般由铁芯、线圈、衔铁、触点簧片等组成的。只要在线圈两端加上一定的电压，线圈中就会流过一定的电流，从而产生电磁效应，衔铁就会在电磁力吸引的作用下克服返回弹簧的拉力吸向铁芯，从而带动衔铁的动触点（常开触点）与静触点（常闭触点）吸合。当线圈断电后，电磁的吸力也随之消失，衔铁就会在弹簧的反作用力返回原来的位置，使动触点与原来的静触点释放。这样吸合、释放，从而达到了在电路中的导通、切断的目的。对于继电器的“常开、常闭”触点，可以这样来区分：继电器线圈未通电时处于断开状态的静触点，称为“常开触点”；处于接通状态的静触点称为“常闭触点”。

2、热敏干

簧热敏干簧继电器是一种利用热敏磁性材料检测和控制温度的新型热敏开关。它由感温磁环、恒磁环、干簧管、导热安装片、塑料衬底及其他一些附件组成。热敏干簧继电器不用线圈励磁，而由恒磁环产生的磁力驱动开关动作。恒磁环能否向干簧管提供磁力是由感温磁环的温控特性决定的。

3、固态式

固态继电器是一种两个接线端为输入端，另两个接线端为输出端的四端器件，中间采用隔离器件实现输入输出的电隔离。

301130

The so-called “safety relay” is composed of several relays and circuits, in order to be able to complement each other’s abnormal defects, to achieve the complete function of the correct and low false operation of the relay, so that the lower the error and failure value, the higher the safety factor, “safety relay” is not “no fault relay”, but to make regular action when the fault occurs. It has a forced guide contact structure, in case of contact melting phenomenon can also ensure safety, which is completely different from the general relay.

The safety relay is the necessary control part of a safety loop, which accepts the safety input and deterministic output switching signal to the control loop of the device through the judgment of the internal loop. Simply put, the safety relay is a two-channel signal type, only when the two channel signals are normal, the safety relay can work normally; During the working process, as long as either channel signal is disconnected, the safety relay will stop output until the two channel signals are normal and reset to work normally.

First, the working principle of safety relay

1. Electromagnetic type

Electromagnetic relays are generally composed of iron core, coil, armature, contact reed and so on. As long as a certain voltage is added to both ends of the coil, a certain current will flow through the coil, resulting in an electromagnetic effect, and the armature will overcome the pull of the return spring under the action of electromagnetic force attraction to attract the iron core, thereby driving the moving contact of the armature (normally open contact) and the static contact (normally closed contact). When the coil is powered off, the electromagnetic suction will also disappear, and the armature will return to the original position in the spring reaction force, so that the moving contact and the original static contact are released. This suction, release, so as to achieve the purpose of conduction in the circuit, cut off. For the “normally open, normally closed” contact of the relay, it can be distinguished in this way: the static contact in the disconnected state when the relay coil is not powered on is called “normally open contact”; The static contact in the connected state is called “normally closed contact”.

2, heat sensitive dry

Reed thermal-reed relay is a new type of thermal-sensitive switch which uses thermal-sensitive magnetic material to detect and control temperature. It is composed of a temperature-sensing magnetic ring, a constant magnetic ring, a reed pipe, a heat-conducting mounting piece, a plastic substrate and some other accessories. Thermal reed relays do not use coil excitation, and the magnetic force generated by the constant magnetic ring drives the switching action. Whether the constant magnetic ring can provide magnetic force to the reed tube is determined by the temperature control characteristics of the temperature-sensing magnetic ring.

3. Solid state

A solid-state relay is a four-terminal device with two terminals as input and the other two terminals as output, and an isolation device is used in the middle to achieve electrical isolation of input and output.