Magnetic Actuator Circuit Breaker?

Thats not much for these folks to go on. There are a BUNCH of ways you could use magnetic field to activate a breaker.

Gavilan

"There are a BUNCH of ways you could use magnetic field to activate a breaker."

I don't understand? Please clarify.

Samak

look under tech papers at http://www.fkiswitchgear.com/downloads/technical-papers

Are you too lazy to:

1. To first Google your question,
2. To at least make yourself clear.

Wagito.

Thanks for advice

Circuit breakers are actuated by two types of current sensors.

Thermal sensors detect overloads, and have a built-in time delay.

Magnetic sensors detect high current faults and are instantaneous.

For some applications 'magnetic only` C.B.s are employed.

Thanks...

But that is not what I'm asking about.

By Magnetic actuator circuit breaker I mean that type of new trend to replace the traditional spring-type mechanism by an electrical coil with embedded special metal alloy. Such a coil if energized by a pulse of dc voltage with certain polarity for a shot period (around 50 msec. only) the embedded alloy will be magnetized for a very long time (years) and a plunger will move to close the CB.

Just a reverse pulse for shorter duration is enough to release that magnetism and the CB to be open.

This technology is recently introduced the market and was firstly developed in Russia and is well known as Magnetic Actuator-Circuit Breaker.

Are there anybody having more details?

However,Thank you for your response.

Samak

<But that is not what I'm asking about.>

So what ARE you asking about?

What do you know about what is called:

"Magnetic Actuator Circuit Breaker" ?

Am I clear now!?

What you are describing in post 7 seems more like a latching relay than a circuit breaker so there may be a nomenclature problem.

Even though a relay "breaks a circuit" the term circuit breaker is used to describe a current overload device that would never depend on an external pulse to open or close the contacts.

I ran a google search with "magnetic latching relay" and came up with some results that may be helpful for you.

Forum's Friends,

What is wrong with this thread!!?

does the thread title means something vague for me while it means something very clear for you!

I feel that there is a mismatch point, result in all of these short-circuited posts including that amount of Wangito's harmonics as posted in #4.

However, thanks for your cooperation and forget this thread.

Ahmad Samak

• BCs. of Electrical Engineering, 1991, Alexandria University, Egypt.
• MSc. of Vector-Control and Direct-Torque-Control based Variable Speed Drives, 2000, Alex. Uni., Egypt.

No more posts like above please.

You wrote, "What is wrong with this thread?..."

We have a saying. "When three persons are telling you that you are drunk, go home and go to bed..."

I have already told you what's wrong. Invest a little time in being clear. Phrase your question in such a way that this forum participants won't need an MSc. or BSc to understand you.

Take it as constructive criticism, and nothing else.

Wangito.

I'm no breaker expert by any means but I'll offer what I do know.

Many circuit breakers employ 2 types of trip mechanisms - thermal and magnetic.

The thermal portion is used for time-overcurrent tripping such as for protection of cables from overheating or melting. It generally employs some type of temperature sensitive device such as bi-metal or melting lead alloy to initiate a trip mechanism and has a time inverse trip characteristic. That is, the higher the overload current, the shorter the time to trip the breaker.

The magnetic type is used for motor protection and utilizes a solenoid or coil and aramature coupled with a dashpot. This device is used for fault current tripping a breaker at some fixed setpoint. The dashpot is used to slightly delay the trip mechanism during the current inrush during motor starting.

Dear,

First, I appreciate your post.

What I do know is that the magnetic tripping element if installed in a circuit breaker, doesn't produce a "magnetic actuator circuit breaker". It is just a circuit breaker with magnetic tripping element.

However, your post is appreciated.

Regards...

Perhaps then your question is regarding solenoid operated (magnetic actuator) circuit breakers? At one time, many of the medium voltage circuit breaker manufacturers used a large solenoid coil to provide the motive force for closing a circuit breaker and charging the trip springs. There are still some in use today but most have been replaced with circuit breakers that use a universal motor for charging (compressing) springs to provide the closing and tripping forces. I think a lot of the 480 Volt circuit breakers may still be using magnetic actuators for closing. Does this help or am I still off-base in attempting to answer your question?

Dear Samek

I read you thread re Magnetic Actuators. My name is Brian Mckean and in fact I inveted the Magnetic Actuator and am the original patent holder. My main licenses include ABB for whome I developed the VM1 circuit breakers in the early 1990's and Cooper power sytems with the Nova reclosers. You can see my company detials at www.eps-uk.co.uk.

I would be pleased to answer any questions you may have about the technology and look forward to hearing from you. Regards Brian