Customers often ask how to choose aluminum shell resistance and winding resistance. Here I will make the following analysis of the characteristics of these two resistors, hoping to provide help when you choose.
   
Overview of aluminum shell resistance
Aluminum shell resistance, the shell is made of aluminum alloy (golden aluminum shell), the surface has heat dissipation groove, small size, large power, high temperature resistance, strong overload capacity, weather resistance, high accuracy, standard low induction resistance, high stability, strong structure, and its flexibility is good for multiple combination selection, which is conducive to mechanical protection and convenient for installation and use.
The role of aluminum shell in the aluminum shell resistance is cooling. The thermal conductivity of metal aluminum is very good. It can quickly transfer the heat generated by conducting the resistance to the surface of the resistance body, and continuously emit heat through the air. The surface of the aluminum shell is designed with more heat sinks, which increases the heat dissipation surface area and also increases the heat dissipation capacity.
The good plasticity of aluminum metal also makes the aluminum shell resistance have better size changes to adapt to the installation space.
The aluminum shell resistor is filled with insulating silicide, which can absorb a certain amount of heat in an instant. Several times the power of the resistance instantaneously.
Overview of winding resistance
The winding resistance adopts ceramic tube as the skeleton, and is evenly wound on the skeleton with alloy resistance wire. The surface is coated with high-temperature resistant insulating coating, which is convenient for installation.
The low resistance value of the winding resistance is 20 Ohm-50 Ohms, which can press the resistance wire into a corrugated shape and stand on the ceramic substrate, so as to increase the usable area of the winding wire and have better heat dissipation performance.
Performance difference between aluminum shell resistance and ripple resistance
Comparison of instantaneous power-on heat dissipation capacity
Due to the fact that the aluminum shell resistance has fillers that can absorb heat, the surface temperature of the aluminum shell resistance will be lower than the winding resistance of the same power after being powered on for 1 s.
Comparison of heat dissipation capacity of long-term power-on
In the case of long-term electrification, the advantages of winding resistance are very detailed. Because the resistance wire of winding resistance can almost contact with air directly (the spacer is only insulating paint), the heat dissipation capacity of long-term electrification will be more detailed than that of aluminum shell resistance.
    
Comparison of insulation performance
In the structure of aluminum shell resistance, there is an insulation layer between the resistance wire and the aluminum shell. The insulation performance can reach 1500V-4000V leakage current less than 2mA according to different requirements, and the insulation performance is very good.
The structure of winding resistance is that there is a layer of insulating paint on the resistance wire, the insulation performance is below 500V, and the insulation performance is not reliable, so it is not suitable to be exposed in a touchable position.
    
Structure comparison
The structure of aluminum shell resistance is stronger than that of winding resistance, and has better vibration resistance.
   
Comparison of installation convenience
Compared with the winding resistance, the aluminum shell resistance has smaller volume, good insulation performance and stronger structure, and is suitable for working in more complex environments.
    
Cost comparison
The cost of winding resistance of the same power should be lower than that of aluminum shell resistance.
    
Comprehensive comparison
Aluminum shell resistance has more advantages in instant energization, insulation performance, structural stability and installation convenience
The winding resistance has obvious advantages in long time electrification performance.
    
When you choose, you can choose according to different stations. We can give the following suggestions:
It is recommended to select aluminum case resistor for motor braking in complex site.
Aluminum case resistor is selected under the condition of limited installation space.
Aluminum shell resistance shall be selected in case of seismic resistance requirements
Aluminum case resistor is selected in case of transient power on and surge
Select winding resistance under long-term load
Select winding resistance under the condition of limited cost and safety protection