motorized breaker

[Hameedulla-Ekhlas]

Greeting all,
Any explaination regarding to Motorized Breaker usage

Thanks in advance

 

[zog]

Greeting all,
Any explaination regarding to Motorized Breaker usage

Thanks in advance

Please be more specific, I have maybe 40,000 motorized breakers of all different types and classes.

 

[LarryFine]

... I have maybe 40,000 motorized breakers of all different types and classes.

You've got all the toys!

 

[Hameedulla-Ekhlas]

Please be more specific, I have maybe 40,000 motorized breakers of all different types and classes.

just the concept. It is first time I heard regarding this. Any type

 

[zog]

just the concept. It is first time I heard regarding this. Any type

Motor charged, spring operated mechanisms can be powered from either an AC or DC source. An electric motor mounted on the circuit breaker turns a cam which charges (compresses or extends) the closing springs on the circuit breaker. The springs hold in a charged or cocked position until a close signal is sent to the closing coil. The closing coil operates and moves the close latch or trigger and the closing springs discharge closing the breaker. Most high amperage circuit breakers (>2000 amps) used as main or tie breakers are motor charged, spring operated. This feature also allows for remote operation of the circuit breakers.

The attached photo is from a motor operated K-3000S viewed from the bottom. The motor is the grey thing in the bottom right of the photo.

 

[SG-1]

You can also get a motorized molded case circuit breaker. The motor & links are external. The breaker can then be operated from a remote location.

 

[Volta]

...

The attached photo is from a motor operated K-3000S viewed from the bottom. The motor is the grey thing in the bottom right of the photo.

Thanks for that summary, not something I've dealt with.

 

[rcwilson]

Motor operators for molded case circuit breakers are usually mounted on the front of the breaker. They take the place of your hand pushing the breaker handle between "OFF" & "ON". Most use a small motor driving a worm screw device with overtravel limit switches to cut out the motor.

Motor-Operated, Insulated Case or Air Frame circuit breakers have the motors and spring charging mechanisms mounted internally like the above picture shows. It takes the place of manually cranking the handle to charge the closing spring.

Some large breakers close as soon as the spring is fully charged and the motor drives the charging cam past top dead center. But most breakers are designed with a separate "Close" solenoid to release the charged spring. The motor charges up the spring and is shut off by the "Spring Charged" limit switch. Then the close command actuates the solenoid that releases the spring, closing the breaker quickly.

The molded-case style motors and others without the spring release solenoid can create timing problems when closing. It may take 1-10 seconds for a breaker to close after it receives the close signal. It takes that long for the motor to move the handle or the spring to charge up and release.

For most applications this delay is insignificant, but it is a disaster on a synchronizing circuit. You send the signal when the voltages are in synch, but by the time the breaker closes, the generator has swung out of synch.

Make sure your application is using the correct style of motor operator.

 

[hillbilly1]

They are getting real popular for use as high amperage transfer switches too, usually electrically and mechanically interlocked.