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How Does A Normally Closed Pressure Switch Work?

Views: 127     Author: China Micro Switch Manufacturer     Publish Time: 2020-08-20      Origin: https://www.unionwells.com/

How Does A Normally Closed Pressure Switch Work?

In case you plan using a pressure switch, it is important to note that there are some aspects which have to be properly understood. Failure to have an in-depth understanding about these parts or components means you will be grouping in the dark. Such can deprive you of optimizing your pressure switch as expected. 

Talking about how pressure switches have been built to function, there is one topic of discussion which seems to be confusing most people in recent times. This is the talk of how “normally closed” pressure switches work. As simple as this may sound, it can determine whether you will get the best from a given pressure switch or not. 

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Here is the major secret

Are you struggling to understand what “normally closed” in pressure switches is all about? Do you know that this is one of the most integral components or parts of a pressure switch? There is no need to bother since you have come to the right place. This post will be revealing lots of secrets about normally closed in pressure switches including how they have been designed to function. Just ensure to read the details below before purchasing a pressure switch in order to be on a safer side. 

Here is the fact

It is crucial you understand some facts about pressure switches. One of them happens to be the point of contacts. There are two points of contact in pressure switches. These are normally closed contacts and normally open contacts. Despite the major aim of this post being to explain more about normally closed and how it has been designed to work in a pressure switch, it is important that normally open contacts will also be explained. This will enhance your understanding about the function of normally closed contact. 

Normally open contact

This is a contact point whereby the switch is going to remain opened. It will remain as such until there is an increased amount of pressure beyond the set point. It should be noted that switches with normally open function are very popular in our everyday life. For instance, light switches have got normally open functions which allows the occurrence of actuation. It is the same with pressure switches as the only difference happens to be the fact that they are majorly used in industrial applications. 

Simply put, it is the normally open function which detects whether a pressure has reached or exceeded its set point. In this case, it can be said that such pressure has exceeded its limit value. In other words, the circuit has been completed by the switch. For instance, this is obvious in a machine where the amount of pressure is being detected. Once it gets to particular level, the machine will either be switched on or off. This is due to the amount of pressure signal which has been detected. The normal open contact determines whether the machine will continue working or not without any human interference. 

Most of the mechanical pressure switches are being used alongside central control system. Through the aid of another circuit, it can drive the safety function. The bottom line is that there is always a set point for every pressure switch to work as expected. It is how the contacts work that determines whether pressure has exceeded the set point or not. 

For instance, a pressure switch contacts can be either normally open or normally closed once the pressure has gone below the set point. In the case of normally open (NO) contacts, the switch is expected to remain open until it gets to a point when the pressure has gone beyond such set point. Now, there is a sensing tool or element that will make the closed position activated. This is the point whereby the machine is not working since amount of pressure has gone above the set point. 

Based on this explanation, it can be said that the normally closed position is that point when the pressure switch has automatically switched off the system due to the fact that the amount of pressure has exceeded its set point. Again, there is set point to be exceeded or reached before the normally closed will remain open again for the machine or system to start working. 

It is obvious that the normally closed in pressure switches has been included to determine when machines or systems will work and stop due to the amount of pressure exceeding or reaching the set point. Now, once contact snap opens, the system is going to function until the pressure reaches its set point again. It goes on and on like this between the normally closed contact and normally open contact in a pressure switch. They are majorly there to determine when a machine will function or stop based on the amount of pressure detected. 

What you should know

It is important to note that majority of pressure switches you will come across in the market do contain two contacts. These are the ones explained above (normally open contact and normally closed contact).  It is important to know that it does not really matter the type of contact which is used for a particular installation, it will always work. Therefore, do not pay too much attention to how your pressure switch has been installed in order to respond to the set point in a machine. 

You only need to understand when it must have snapped back normally open position or normally closed position. There is no set in stone or golden rule about how this works. What is important is your understanding of how it has reached its set point based on the amount of pressure detected.  

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Based on the above, it is obvious that normally closed works in a clear and simple way in pressure switches. It is the same as what applies in micro switches or limit switches that are meant for domestic uses. You just need to make out time in order to understand how it works. It is much easier than you must have imagined initially.

For more about pressure switches,you can pay a visit to unionwell at https://www.unionwells.com


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