Temperature kills electric devices. It has a bad effect on cables, motors etc. In this article I will discuss How does Temperature affect electrical equipment.
How does temperature affect electrical conductivity?
We know that metals are great conductors of electric current because of the free electrons present. When you increase the temperature, electrons’ motion increases, which can cause unintentional collisions, resulting in an increase in resistance in the metals. The electrons’ mobility reduces, which causes a lower conductivity.
In other words, the conductivity of an electrical wire or cable will diminish as increasing temperature!
How does temperature affect resistance?
The impact that temperature on the conductor’s resistance is directly proportional to each other. So, the rise in the temperature of the conductor will increase its resistance, making it more challenging to draw the current through it.
The free electrons that move around the metal conductor collide with other electrons, generating heat; the collisions increase as the metal conductor generates more heat.
They create obstacles to the conductor’s electrons’ further movement and cause more resistance. Thus, the increased temperature of the conductor will increase resistance within the conductor.
Resistance is usually an opposing force to the body’s movement and reduces the body’s ability to perform. For example, in the field of electricity, it is the resistance provided by the material against the flow of electricity through it.
The S.I unit to measure resistance is the ohm. The temperature-on-resistance varies for a semiconductor, conductor and insulator.
The conductor‘s resistance will vary based on various variables, including the material used to construct the conductor that makes up the conductor’s dimension, the ambient conditions, and more. Temperature is also a crucial element that alters the conductor’s resistance.
The flow of electricity through conductors is simply moving electrons in the conductor. However, the electric field generated inside the conductor can influence the motion of electrons. The induced electric field creates an electric potential over the conductor, which initiates electrons’ movements toward the opposite terminal.
How does temperature affect wires and cable?
Temperature is an essential concept to comprehend. If something’s too hot, it will melt or catch fire; when it gets too cold, it will freeze or break.
Read also my other articles: Motor temperature rise causes and effects.
Affect of hot temperature on wires and cables
Hot temperature can cause cables to become over heated. Remarkably, it raise the resistance of wires because it force cables to expand, making the flow of electricity through them harder, making an electrical wire less efficient. This can increase the chance of occurring in the conductors made of aluminum from the utility wire that is part of the overhead electric power line.
The cable’s insulation can withstand thermal stress also. The insulation could melt and cause electrocution or fires. If the cable doesn’t possess the proper temperature rating, it can occur during the extremely hot summer months.
But, the consequences of excessive heat are particularly significant in the industrial environment that places cables exposed to extreme temperatures. In these instances, only the cable has an insulation type capable of withstanding extreme heat that can function.
Affect of cold temperature on wires and cables:
Cold temperatures, particularly the highly frigid winter temperatures, can be detrimental to cables. They result in conductors of cables losing heat, which affects the performance of the wires. The main factor that affect cables current carrying capacity is its temperature.
Another weakness regarding cables in colder temperatures is that lines are becoming more rigid to the point of breaking.
Setting up electrical cables in cold winter months can be challenging, and it is not recommended. In addition, certain kinds used for cable insulation like PVC, which is the most common type of PVC, might become stiff due to the force of cold temperatures.
In the case of overhead power lines, wind sagging and ice accumulation are frequent issues that can lead to losing power. But, like the heat, careful and prompt management by utilities is the most effective solution.
How does temperature affect an electric motor?
If the temperature inside the motor is higher than the value of its heat class for a time, the winding films melt, and the film shortens. This is referred to as burnout.
The motor that has been burned out will cease to function. In addition, if the motor is not completely burned, then the rise in temperature affects the motor’s lifespan. Therefore, while operating, ensure not to exceed the allowable winding temperature.
As the winding temperature within the motor is not determined directly, you must measure the temperature outside of the motor’s case to examine for a reference.
What causes motors to overheat?
If you’re concerned about the rise in temperature within the machine, examine the surrounding environment. These are some an example of the factors that cause the excessive temperatures of the motor:
A motor that is not suitable: Motors is available in various sizes. Select a motor that can handle the power and performance levels required for your particular project. An engine that’s not massive will use up energy and cost you money, while a too-small motor won’t be able to handle a large load, resulting in increased stress and heat.
The incorrect voltage supply: The wrong voltage supply: Too many volts or a small number of volts could harm a motor. If your motor isn’t equipped with the proper voltage support, it has to work harder to function, which can cause components to overheat.
A poor environment A motor requires enough airflow so it can function optimally. If the machine operates in a hot, humid climate, it’s likely to struggle to cool down fast. Make sure that the motor has plenty of space to run.
Improper Use: Some motors may be run continuously, while others are designed in intermittent intervals. It is essential to utilize your motor under the specifications of the motor. If you attempt to operate an infrequent duty engine for too long, the motor will not get the time to get cool between cycles.
Altitude Your location and the area of your business will affect your motor’s performance. Your motor may not cool as well in higher elevations since the air density is lower. It’s crucial to select a suitable motor for the location of your workshop.
An absence of ventilation If something is blocking the vents for your electric motor, the hot air can’t escape and can accumulate in the system, which can cause harm. Making sure you schedule regular maintenance for your motor may reduce the chance.
Can electric motor work in low temperature environments?
An electric motor can work at low temperatures but operating a motor in cold conditions can cause additional concerns. Overheating is a significant danger.
Overheating could occur when ventilated motor enclosures are covered with snow or ice. It can be caused by an overload condition or pushing the motor into a service or a factor. The operator needs to ensure that they adhere to the motor’s operating guidelines as usual during colder weather.
When temperatures are lower than -20° C or higher than 40° C, operators need to take extra care of components such as grease, bearings, seals, fans, insulation or leads. They’re among the most frequently encountered issues of running electric motors in hot and cold conditions.
There are several specific components to be concerned about if temperatures drop below -20 degrees C, such as fans, seals, and the grease inside the bearings. Some plastics and elastomers turn fragile in cold temperatures, so alternatives to climate-tolerant materials that use silicone should be considered instead of neoprene.
The seal made of nitrile rubber could be more effective with metal seals or enhanced nitrile compounds. The motor’s lubricant should keep a sufficient viscosity at these temperatures to lubricate all rub components.
Cold weather is also a cause for concern regarding the safety of Class I explosive-proof engines. The pressure to ignite combustible gas tends to be greater at colder temperatures. Flame paths and enclosures that are explosion-proof should stand the increased pressures associated with a cold environment.