Functions of main and auxiliary contacts of molded case circuit breaker:

1、輔助觸點起到傳達斷路器的工作狀態(tài)信號的一個作用。為控制回路提供互鎖接點；為信號回路提供斷路器的分合位置狀態(tài)；為保護回路提高跳閘接點；

1. The auxiliary contact plays a role in transmitting the working state signal of the circuit breaker. Provide interlocking contact for control circuit; Provide the opening and closing position status of the circuit breaker for the signal circuit; Improve the tripping contact for the protection circuit;

2、輔助觸點與主觸點是同時動作的，是機械結構關系，扳主觸點的同時有內部機構帶動輔助觸點同步動作。輔助觸點通常是一個常開加一個常閉結構：主觸點閉合則輔助觸點常開觸點閉合，常閉觸點斷開；主觸點斷開則常開觸點斷開，常閉觸點閉合。

2. The auxiliary contact and the main contact act at the same time, which is a mechanical structure relationship. When pulling the main contact, there is an internal mechanism to drive the auxiliary contact to act synchronously. The auxiliary contact is usually a normally open plus a normally closed structure: when the main contact is closed, the normally open contact of the auxiliary contact is closed and the normally closed contact is open; When the main contact is open, the normally open contact is open and the normally closed contact is closed.

那么，如何判斷塑殼斷路器觸點接觸的好壞呢？

So, how to judge the contact quality of molded case circuit breaker?

1、在選擇斷路器的時候要根據電流的等級進行選定，一般情況下，選定后就不會出現圖片所示的情況；

1. The circuit breaker shall be selected according to the current level. Generally, the situation shown in the picture will not appear after selection;

塑殼斷路器觸點打火，引燃了上方的控制線槽

The contacts of the molded case circuit breaker ignited and ignited the control trunking above

2、檢查觸點接觸的好壞，還是拆開來檢查比較穩(wěn)妥。之前用過一種方法，就是在設備送電正常運行的時候，用非接觸式的測溫槍進行溫度檢測，對每相靠近觸點的位置進行檢測，對溫度值進行比較；

2. Check whether the contact is good or bad, or it is safer to take it apart. A method has been used before, that is, when the equipment is powered on and running normally, use a non-contact temperature measuring gun to detect the temperature, detect the position of each phase close to the contact, and compare the temperature values;

3、檢查產品是不是哪個地方接觸不好，接觸不好肯定溫度會升高，引起自燃的情況；

3. Check whether the product is in bad contact. If it is in bad contact, the temperature will rise and cause spontaneous combustion;

注：以上的檢查情況，是根據多次事故發(fā)生的經驗，總結出來的可能會造成這種現象的原因，但實際情況是觸頭的阻值受環(huán)境影響變化很大，比如溫度濕度以及灰塵都會影響到觸頭的阻值，因此無法通過一個標準阻值來衡量觸點是否已損壞。

Note: the above inspection conditions are summarized based on the experience of many accidents, which may cause this phenomenon, but the actual situation is that the resistance value of the contact changes greatly affected by the environment, such as temperature, humidity and dust will affect the resistance value of the contact, so it is impossible to measure whether the contact has been damaged by a standard resistance value.