Pressure Switch

jklee

No, I will not explain it to you. If you have enough smarts to find CR4, then you can certainly use a search engine (such as Google) to find the information you seek. This site is not meant for those who are too lazy to find some rudimentary information for themselves.

Mike

ok. let me rephrase my question. is there any godd link or website that explains the items above as I have tried to search using Google but I could not find any website which have good explanation.

P/S: Mikerho, I think that your words are kind of rude and you should offer an apology.

Hi jklee,

After your reply, I tried looking for a good how-a-pressure-switch-works site, but, I also, could not find one! My apologies. I thought that something as basic as the operation of a pressure switch would be all over the net!

I only know about the pneumatic pressure switch. The pneumatic pressure switch has a diaphragm that positions itself according to the amount of pressure applied to it. On the other side of the diaphragm is an adjustable lever that, when touched by the diaphragm, is tripped, causing contact to be made between two (or more) electrical terminals. When pressure to the diaphragm decreases sufficiently, the lever "switches" the other way, breaking contact with the terminals.

I suspect very strongly that a "pneumatic pressure switch" and an "electrical pressure switch" are the same thing. Pressure = pneumatic and switch = electric.

Hope this helps,

Mike

P.S. Sorry for being so blunt, but it DID elicit a little more detail from you.

Hi Mike,

Please don't set rules like this on the Internet! Thanks!

No question is stupid or not worthy of answering!

The simple thing you know might just be the difficult things for the others, it is certainly for people like me!

On the other hand, I know there are peso-electric transducers and even material that would convert pressure to electrical signals (most likely voltage) directly that tells the magnitude of the pressure under sampling. What about this?

Cheers,

Guest

I usually do not reply to non-identified posters, But I will do an exception this time.

Guest, you are totally missing the point . CR-4 is not an elementary school forum. It is as it's heading clearly stipulates,

If you don't know the difference between Peso-electric (what's that?) and piezoelectric, or don't know about load-cells strain-gauges and dozen of other pressure sensing devices, whether voltage, resistance or current, than this forum may not be for you as well and definitely not for a question such as has been posted. We do not mean that these shouldn't be answered, or trying to discouraged people from learning, on the contrary, we only try to keep a minimum entry level.

There are many other forums such as wiki-Answers etc. which are much better suited for the purpose.

Wangito.

This is also "The Budding Engineers Place...". You were there once too. Let's not shut out anyone reaching out to learn.

What about a minimum entry level for grammer?????????

....and spelling?

Read what you wrote again!!!

If you don't like the truth, go and do the legwork yourself instead of asking here.

He could have called you a "Lazy ***** " but he didn't!!!

Be thankful for small mercies!!

Nor should he offer an apology for telling the truth!!

http://en.wikipedia.org/wiki/Pneumatic_pressure_switch

Interesting. Wikipedia, which tries to get all of us to write its content only answers the question by not answering it, rather simply describing in general terms what one such does.

Guess they don't get many engineering or industrial maintenance types. I rarely go there because I want authoritative answers.

I am an old industrial maintenance type. In that vein I know everything except air and refridgeration although of course I know it theoreticaly, i.e., I understand it but can't fix it.

Since, for a time I attended Brooklyn Tech and was subjected to such things as their Industrial Processes class and their foundry operations, machine shops, of course physics, chemistry,etc., I reatain a lifelong interest in all such.

I must admit that the question raises thoughts of all the things I had not thought about except perhaps when trouble shooting my van.

But as to pressure swithches, guages and such, I never dreamed, given the replacement of the mercury sphygmomenometer, i.e., mercury column, for reading blood pressure with something that probably relies on a transducer, peizeo or otherwise, I would be pleased, in the absence of the aforesaid mercury column to have my blood pressure measured by one of the circular dial, mechanical, stressed disc types rather more stable than the electronics which are notoriously unreliable and have caused serious medical problems.

All this aside, I find these simple appearing questions interesting insofar as many are from folks far from us here in the U.S. but who in their workaday world require answers to questions that are routine to us favored of the technical world.

Jack Jersawitz

This link to Global Spec is a great link! The CR4 search engine will often take you more quickly to a pertinent reference than will Google, because engineering topics are its principal concern.

Hi Guest,

I gave you 1 point for a "good answer". Too bad it will not count since you are not signed up.

Mike

Mike,

Setting rules like this up and fencing people off would not promote progress. Human achieved so much because our ancestors were all willing to take on whatever it needs to advance! Galileo did that, Einstein did that...

If I may say so, people walking in the science/technology arena keep setting rules up to protect themselves/fence others off, would only serve to delay development, hinder advancement or even block our adventure in the Universe; should not stay!

No matter he/she sign in or not, a good answer is a good answer!

Guest.

What rules?

Hi stevem - OK I'll believe you! So here's one. Someone else will have to follow up and give you another for you to get a good answer.

Anyone...

Mike

jklee,

Are you still there? It is important (at least to me) to know whether our replies were helpful or not. In the case that you have been very busy with other things, please get back here when you have a moment.

Mike

In pneumatics there are two types of pressure switches. Referred to as PE switch and EP switch.

The PE switch is a pneumatic (pressure) operated electric switch, set to close or open an electric circuit at a set pressure. Example would be when pneumatic rm t'stat opens a (chilled or hot) water valve, a PE switch in the control air (branch) line to the valve would energize the water pump.

The EP switch is an electric operated pneumatic pressure switch, set to open or close a pneumatic air line when it is energized. Example would be when an air handling fan is de-energized, the EP switch is also de-energized, closing the pneumatic line rendering it inoperative. Pneumatic controls, more or less, continiously bleed air during their operation.

______________________________________________________________

Sometimes you get, and sometimes you get got!

You didn't find it in google? You must be kiddi'n,

The question "How does pressure switch work" brought 550,000 answers in less than one second. Go to wiki-answers for example.

Wangito.

Post by Guest is very good.

All I can add is:

Be careful of definitions and context:

A pneumatic pressure switch may be a pressure sensing erlement in an air system (compressor system), which actuates a set of electric contacts (for example, to switch ON/OFF the motor in order to load/unload the compressor).

On the other hand, it may be a pressure sensing element in any kind of pressure circuit (water, oil, etc.) which actuates a pneumatic on-off valve, diverting or venting air pressure from a pneumatic logic system.

Which one is yours?