The mention of intermediate relay, I believe that most electricians are very familiar with it, and it is often used in actual electrical wiring and maintenance operations. Generally, small intermediate relays are mainly used in low current working conditions. Generally, intermediate relays will not burn out frequently. However, in practical electrical work and maintenance wiring, the intermediate relay is often burnt out frequently, and today we will focus on the reasons why the intermediate relay is often burnt out:
First, let’s take a look at some burnt-out intermediate relays:
Burnt-out phenomenon: The coil has turned black and deformed, and the contacts of the intermediate relay are stuck together.
Second, picture analysis of frequent burning of intermediate relays:
1. Distinguish between AC and DC.
When using intermediate relays, you must be clear about whether it is AC or DC, and do not mix them. AC refers to alternating current, and DC refers to direct current. Pay attention, or it is easy to burn out the intermediate relay!
2. The working voltage of the intermediate relay coil!
Common DC intermediate relays include: 12V, 24V, 48V, 110V, and 220V, with 24V, 12V, and 220V being the most common! Common AC intermediate relays include: 110V, 220V, 380V, and 220V and 380V are especially common.
Be sure to distinguish the working voltage during use! Otherwise, the intermediate relay will burn out directly, which is very important!
3. How to use the intermediate relay!
Generally, intermediate relays will not directly drive large power loads or devices. Otherwise, they will burn out directly. When an intermediate relay is needed to control a large power load or device, it can be matched with an AC contactor. Use the intermediate relay to control the coil of the AC contactor, and indirectly control the large power load by controlling the AC contactor to close or release!
Important reminder: The contact capacity of the intermediate relay is generally around 5A, which means that the intermediate relay can directly drive loads under 5A, similar to the use of an AC contactor, and can be used interchangeably. However, if the current exceeds 5A, the intermediate relay is not allowed to directly drive the load, which is very important!
4. The circuit symbol of the intermediate relay.
The circuit symbol of the intermediate relay “KA”. Generally, the intermediate relay does not have a main contact, only auxiliary contacts, which can be divided into normally open point NO and normally closed point NC. AC contactors have main contacts, so be sure to distinguish them.
In conclusion, there are definitely more than just these 3 reasons for intermediate relays to burn out. If you have encountered this in your work, you can share your experience in the comments below. What reasons caused the intermediate relay to burn out? Let’s exchange and learn from each other about electrical knowledge and skills!