Lang Jun leakage circuit breaker JMR-63

JUNON) JMR bipolar leakage circuit breaker 63A 04/07

Brand: JUNON model: C JMR263C/30E Rated voltage: 230V~ Rated current: 63A

￥59.53

Five starts

Fixed: Legrand, Qisheng, Matsushita Electric, Simon, TCL, Matsumoto, Flying Sculpture, Chint, Bull.

Move: Breakthrough, Bull, Inteman, Bullet.

PDU:APC, clervaux, breakthrough

Exit: Hongyi

Guide to switch selection

Look at the shell material first. The main switch brands in the market generally choose PC material, also called bulletproof glue. The characteristics of impact resistance, high temperature resistance and difficult discoloration are very important for controlling electrical switches. The front panel and rear base of a better switch are made of PC, but the general switch will use black nylon instead of PC on the base, which can reduce the cost a lot.

Also using PC material, many household products in Kai Guanchang are made in China (even if the standard is American GE, they are actually produced by domestic cooperative factories and only sold by GE). At present, in fact, no company in China has the ability to produce PC materials, and the so-called domestic products are generally reprocessed with recycled materials, so there are more impurities, which will be brittle and have obviously poor heat resistance. In order to reduce the cost, the bad switch may be replaced by mixture or ABS instead of PC material on the front panel. These materials are not only poor in impact resistance and heat resistance, but also easy to change color, and the surface is rough when touched too much.

Secondly, look at the contact point, which is the contact point of the conductive part in the switching process. Contact depends on size (bigger is better) and material.

At present, there are mainly three kinds of contacts, silver-nickel alloy, silver-cadmium alloy and pure silver.

Silver-nickel alloy is an ideal contact material at present, which has good conductivity and hardness and is not easy to oxidize and rust.

Silver-cadmium alloy contacts are also good in other aspects, but cadmium is a heavy metal, which is harmful to human body on the one hand, and its fusion with silver on the other hand is not ideal. Small cadmium particles will be formed on the contact surface, which may pull out the arc when conducting electricity.

In fact, pure silver is not suitable for contacts, and its conductivity is really good, but it is soft and easy to oxidize (like silver jewelry will turn black after a long time). Soft texture, switch deformation contact more; If oxidation rusts, the conductivity will be much worse, and the rust spots will easily heat up and melt the contacts.

Third, look at the structure. At present, it is mainly a large panel type, and its appearance and feel are better than the previous thumb type. The biggest problem of thumb type is that it is easy to jam, because short torque, small switch action range, slightly small or hard spring may lead to switch jam. I saw Gray (don't tell me it's American, if it's American, I'm a Martian) turn off a so-called reset switch the other day. Try to feel rough. I opened it and found a small roller inside. Press it and turn it 1/4 times. In order to reduce the inevitable friction, it was coated with lubricating oil. Imagine how to use the lubricating oil in this switch after half a year.

In addition, the power of household appliances is getting bigger and bigger, and the requirements for switching loads are higher, especially at the moment when the appliances are powered on (many inferior switches are burned out by instantaneous high current). A good switch should be able to pass more than 16A, and an ordinary switch can only pass 10A at most.