We have heard a lot that, people below 50 kg can’t enter a substation. Some has given some funny explanation about this. Some said that the magnetic field made by high voltage attracts people with weights below 50 kg. But this is not the right reason. Today we will discuss electrical substation safety.
Why people below 50 kg weight can’t enter substations?/Electrical Substation Safety
Capacitive Discharge Current
In reality, electricity does not pull things from 20-25 feet away. But the capacitive current can be discharged because of high voltage. Because the human body is fleshy and swelling. So human body works as a capacitor in high voltage. Actually, IEEE has published the rule of 50 kg people can’t enter the substation. We know that,
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IB = k/√ts
Here, IB is body current, k is constant, and t is the time of current affecting the person.
On the other hand,
k = √SB
Risk of Cardiac Arrest
Here is a shocking probability of body. AC current is risky for the human body. Because AC has not much reaction in a resistor.
So, AC can affect the heart of any human or animal and cause cardiac arrest. AC means synchronized current. It means sometimes positive cycle and sometimes negative cycle. Heart tissue can’t tolerate this synchronization. And because of this, the heartbeat increases from normal and harms the heart.
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According to research, if someone with a 50 kg weight stays in high voltage, his capacitive voltage body current is 116 mL ampere and it starts to affect the body in 3 seconds. Which can be very dangerous for him. Basically for this reason it is prohibited for a person below 50 kg to enter the substation. The weight is actually measuring if the person is an adult or not.
Can a person with below 50 kg weight work in a substation?
It won’t matter if a person’s weight is below 50 kg. Because it is normal for an adult to have more weight than that. But in case someone has a weight below 50 kg, then he has to take some extra precautionary steps before entering the substation.
That was all for today’s article.
If you have any questions on electrical substation safety you can ask in the comment section.
You can also read: Why is DC Supply Used in Substations?
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NEC, BS7671, AS/NZS, CEC, and DIN VDE covered
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