Ordinary type junction box
It is characterized by its simple construction and ensures that the terminal block and protective tube are firmly connected to the junction box. The connection between the different wires and the temperature sensing element is connected by the binding post, which has good electrical contact performance.
Ordinary junction boxes are usually used in places with good environmental conditions and no corrosive atmosphere.
Pluggable junction box
It is characterized by easy assembly and disassembly, and the standard products of the connector manufacturer are selected.
It prevents dirt from entering the inside of the junction box and ensures good electrical contact performance, so it is suitable for dry and dusty sites. It can be quickly disassembled and assembled when in use, thus reducing the impact of high temperatures or dust on operators.
Splash-proof junction box
It has the following characteristics:
1) the cover 4 of the junction box is fixed on the junction box body 1 with two non-coming out screws (i.e., the screws do not fall off after the cover is opened);
2) The cover is bolted with a chain 5, when the cover is opened, because the chain is bolted, the cover will not be lost;
3) The sealing of the cover and the junction box body is made of heat-resistant black eraser;
4) the sealing of the outlet hole is to use black rubber as sealing ring 8, and then press and clamp the connecting wire with the outlet bolt 7;
The splash-proof performance of the splash-proof junction box should withstand the splashing test of artificial rain with a rainfall of 5 mm / minute, and the horizontal plane at an angle of 45 ° for 5 minutes.
Thermocouples and RTDs for these junction boxes with splash resistance can be used in sites where there is frequent splashing of water vapor or where there is a lot of humidity or dust.
Waterproof junction box
Its structure is compared with the splash-proof junction box, except that the lid 2 and the junction box body L are different in connection, the structure of other parts is the same.
The structural characteristics of the waterproof junction box are that the cover 2 of the junction box and the junction box body 1 are connected with threads. Relying on the tightening force of the cover and the junction box, the sealing ring made of heat-resistant black rubber is evenly pressed throughout the circumference, so that even if there is serious water vapor or harmful gas, it will be blocked by the well-sealed sealing ring and will not penetrate into the inside of the junction box.
The waterproof performance of the waterproof junction box should withstand a distance of 5 meters, spray water in any direction with a faucet with a nozzle diameter of about 25 mm, and the water pressure before the nozzle outlet is not less than 2 kg/cm, and the test lasts 5 minutes.
Thermocouples and RTDs for waterproof junction boxes are suitable for sites where water is often sprayed, such as when the equipment is installed in mold or indoors and needs to be cleaned frequently. In addition, the waterproof junction box is easy to assemble and disassemble, and after the lid of the junction box is opened, it is tied to the junction box body with a chain, so it will not be lost, which is more suitable for high-altitude equipment.