Kamis, 26 Mei 2011

What is the difference between control panel and MCC?

You know what is control panel and what are the components used in the control panel. Now we will discuss about difference between control panel and MCC. You might have faced this question in some interviews.

MCC stands for motor control center. It consists of feeders for motors and blowers. Feeders are designed according to the motor rating. In most of the MCCs, auto/manual provision will be there. With manual provision motors can be operated manually. In auto provision external signal is required to start the motor. The signal is given by the control panel. Indicators for the motor operation also will be present in control panel.
mcc- motor control center- control the motor by recieving signal from control panel




















Control panel consist of a controller. Controller may be PLC, DCS, relay or some other type. It gives digital signal input signal to the MCC panel to start the motor. Control panel works based on the PLC /DCS program or the relay logic.  Instruments are normally connected to control panel. Indications for the interlocks also will be there in control panel. Nowadays single panel is used of using separate control and MCC panel.

control panel - PLC/DCS/relay recieve inputs from instrument and give outputs to MCC















Overview: Control panel giving start command to motor through MCC

How control panel control motor through MCC










Related post:
Know more about control panel.
Learn to read electrical relay drawing.
Basics of electrical.



Selasa, 24 Mei 2011

How to read electrical relay diagram? [Standard symbols used for drawing electrical relay diagram]

In one of the previous post in instrumentpedia I have described how to read an electrical drawing. Now lets look what is electrical relay diagram. Here I am giving the standard symbols used for the electrical relay diagram. In earlier days instead of PLC or DCS like controllers relays are used as controllers. Nowadays also for controlling small systems relays are using as controllers. Comparing to other controllers it is very cheap. Electrical control circuits are drawn with the standard symbols which are given below.

Components used for making a electrical control circuit and its standard symbols.

Switches.
Selectors.
Push buttons.
Contacts.
Coils.
Motors.
Pilot lights.
Alarms.
Connections
standard symbols electrical relay diagram- switches-pus button-connections
electrical relay diagram alarms motor hooter contacts

Related post:
Learn to read an electrical drawing.
Basics of electrical engineering
Electrical control panels
Piping and instrument diagram


Sabtu, 21 Mei 2011

The only thing left.

Seriously. I can't even tell count the number of times this has happened to me.
Left-handed people are the silently oppressed in this world. 

Jumat, 06 Mei 2011

The God of Thunder.

I saw the midnight release of the Thor movie, which is now out in most theaters.

Long review short, I enjoyed it. I didn't fall in love with it like I did Ironman, and I didn't detest it. Perhaps I am biased. I am a superhero fan, and would most likely have a somewhat lower opinion if I was not.

Though, as I said, I enjoyed it. I was entertained. Ultimately that is the point of movies.
There was plenty of action, plenty of laughs, and enough special effects to make you say "whoa, what the shit" repeatedly. Although the camera movement was a little too fast for my taste, blurring out a good portion of the fight scenes.

Also eye candy. Mostly for the women, but still. They give you Natalie Portman, so stop complaining. Honestly, her acting could have been much worse. I guess that's a high point?
The movie throws you in at a comfortable starting point, and introduces the characters and backstory at a relative pace. You don't have to be a comic fan to understand what's going on, which is exactly what they were going for.

Then you get some cool fighting scenes, with giant face-lasers, a giant ice-themed Rancor and a bunch of blue people from Avatar.

[If you want to keep the movie a surprise, I would stop reading about here.]

After that some plot is thrown your way, and Thor is exiled to Earth (a.k.a Midgard). For a day. This is ridiculous to me; after a couple thousand years being Thor, the god of thunder who has had dozens of lifetimes to develop a concrete persona, he becomes a humble man and changes his outlook. It must have been something at that Denny's diner. Probably the pancakes. Or maybe Natalie Portman as Jane Foster is just that hot. (Hint: no.) He probably fell in love with the bars. I have no apathy for New Mexico. Not even people who live there are fond of it! So why would Thor?

Ultimately, if you have the $10 to shell out for a movie, I would say go for it. Did you seen Ironman? The sequel? Yes? Good. Then you will enjoy this, and you will most likely enjoy the upcoming Captain America movie.

Now that is what I am excited about.