The so-called intermediate relay is used in relay protection and automatic control system to increase the number and capacity of contacts.

它用于在控制電路中傳遞中間信號。

It is used to transmit intermediate signals in the control circuit.

中間繼電器的結構和原理與交流接觸器基本相同，與接觸器的主要區別在于：接觸器的主觸頭可以通過大電流，而中間繼電器的觸頭只能通過小電流。

The structure and principle of the intermediate relay are basically the same as that of the AC contactor. The main difference from the contactor is that the main contact of the contactor can pass through large current, while the contact of the intermediate relay can only pass through small current.

因此，它只能用于控制電路中。

Therefore, it can only be used in the control circuit.

它一般是沒有主觸點的，因為過載能力比較小。

It generally has no main contact, because the overload capacity is relatively small.

因此，它用的全部都是輔助觸頭，數量比較多。新國標對中間繼電器的定義是K，老國標是KA。一般是直流電源供

Therefore, all auxiliary contacts are used, and the number is relatively large. The definition of intermediate relay in the new national standard is k, and the old national standard is Ka. Usually DC power supply

中間繼電器作用是用來傳遞信號或同時控制多個電路，也可直接用它來控制小容量電動機或其他電氣執行元件，它的結構和交流接觸器基本相同，只是電磁系統小些，觸點多些。

The function of intermediate relay is to transmit signals or control multiple circuits at the same time. It can also be directly used to control small capacity motors or other electrical actuators. Its structure is basically the same as that of AC contactors, except that the electromagnetic system is smaller and there are more contacts.

繼電器的工作原理是當某一輸入量(如電壓、電流、溫度、速度、壓力等)達到預定數值時，使它動作，以改變控制電路的工作狀態，從而實現既定的控制或保護的目的。在此過程中，繼電器主要起了傳遞信號的作用。

The working principle of the relay is to make it act when an input (such as voltage, current, temperature, speed, pressure, etc.) reaches a predetermined value, so as to change the working state of the control circuit, so as to achieve the established purpose of control or protection. In this process, the relay mainly plays the role of transmitting signals.

常用的中間繼電器主要有JZ7系列和JZ8系列兩種，后者是交直流兩用的。在選用中間繼電器時，主要是考慮電壓等級以及常開和常閉觸點的數量。

There are two kinds of commonly used intermediate relays: JZ7 series and jz8 series, which are AC and DC dual-purpose. When selecting the intermediate relay, the voltage level and the number of normally open and normally closed contacts are mainly considered.