February 18, 2019

Measures against static electricity: Related problems (part 1)

ESD-measures

No more static electricity!

Winter is the favorite season for static electricity to arise. This moment when you grab an object or touch someone and a small spark of electrical discharge happens. Everyone has encountered this “electric shock” once, quite a nasty  wake up feeling.

Static electricity, the trouble maker on the production site

Static electricity is happening not only in winter but all year around.

In general, the potential charged perceived by the human body is said to be several kV. However, when the charged is around 1kV, our body hardly feels it. At a production site, on the contrary, a static electricity even less than 1 kV can cause serious damages (see Table 1).

Table-1.-Problems-with-static-electricity-by-industry-(example)

Table 1. Problems with static electricity by industry (example)

How does static electricity occurs?

The factors can roughly be divided into three categories:

  1. Abrasion charging: Charges by rubbing objects.
  2. Peeling electrification: Charging by peeling / separating the object in contact.
  3. Inductive charging: When the charged object approaches the conductor, the polarity on the conductor, with an opposite charge to the polarity of the charged object, gathers on the surface of the conductor, thereby charging.

Static electricity generated by these factors is a trouble maker on the production site.

In order to prevent issues caused by static electricity, various anti-static measures will be implemented at the production site (see Table 2).

Table-2.-Antistatic-measures-(example)

Table 2. Anti-static measures (example)

How to solve static electricity problem? With anti-static measures

In order to prevent static electricity issue, these are three ways:

  1.  Release the generated static electricity ;
  2.  Neutralize the generated static electricity;
  3.  Prevent static electricity from happening.

Even though you can purchase goods or improve your installation to release and/or neutralize the generated static electricity, these are corrective measures.

Between these three measures, the best way is to prevent static electricity from happening.

The solution is “to create an environment where static electricity does not occur”.

However, there are advantages and disadvantages to each measure, so you have to choose the method that suits your production site the best. It can happen also that you need to use several methods together.

Next time, we will introduce a solution to prevent the static electricity to happen with humidification and explain you a little more about the “humidification” method.

Takahide-Muto