BEE 1961,
Test venue for each section as below:
E11: Industrial electronic lab (F8)
E12: Industrial electronic lab (F8)
E13: Machine control lab (F13)
Reminder: Test schedule as below
Date: 15-April-2011(Friday)
Time: 2.30 pm
Wednesday, April 13, 2011
Industrial application of Star Delta starter
Star Delta is categorize as a reduce voltage method
Reduced voltage methods are intended to reduce the impact of motor starting current on the power system by controlling the voltage that the motor sees at the terminals.
Common applications which require controlling the starting current or torque can be found in many industries including material handling, HVAC, mining, and waste water treatment where the main applications are fans, pumps, conveyors, and compressors.
This circuit allows the motor starter to initially connect the leads in a star connection for starting, and then reconnect them in the delta configuration for running
This method is usually employed on motors rated below 600V. Motors rated 2.3kV and higher are usually not suitable for Star-Delta starting. In term of power, it is suitable for motor rated above 7.5 Hp (5.5 kW)
Fans can be either directly connected to the motor or belted. The fans that are belted usually require torque control during starting to eliminate or reduce excessive belt wear as a result of slippage during across the line starting.
Pumps have low starting torque profiles. The initial torque and acceleration torque can be critical in some pumping applications and is usually determined by the design of the pump. Some pumps such as those with long shafts connecting the motor to the pump, may be damaged if the starting toque is too high.
some types of compressors need low torque to accelerate to full speed. Reciprocation compressors require high starting torque especially when starting under load. Other types such as centrifugal and axial vane type require low starting torque because of the design characteristics.
The need to limit the inrush current may be due to government mandates, power company restrictions, distribution system limitations, or operation in areas that are adjacent to or within a residential area may need to limit current during starting to eliminate voltage drops that cause light flicker.
A good example of this is on pumps for hydraulic elevators in an apartment complex. These pumps have low starting torque requirements, so limiting current during starting minimizes any line sags that would have occurred if the pump was started direct on line.
Reduced voltage methods are intended to reduce the impact of motor starting current on the power system by controlling the voltage that the motor sees at the terminals.
Common applications which require controlling the starting current or torque can be found in many industries including material handling, HVAC, mining, and waste water treatment where the main applications are fans, pumps, conveyors, and compressors.
This circuit allows the motor starter to initially connect the leads in a star connection for starting, and then reconnect them in the delta configuration for running
This method is usually employed on motors rated below 600V. Motors rated 2.3kV and higher are usually not suitable for Star-Delta starting. In term of power, it is suitable for motor rated above 7.5 Hp (5.5 kW)
Fans can be either directly connected to the motor or belted. The fans that are belted usually require torque control during starting to eliminate or reduce excessive belt wear as a result of slippage during across the line starting.
Pumps have low starting torque profiles. The initial torque and acceleration torque can be critical in some pumping applications and is usually determined by the design of the pump. Some pumps such as those with long shafts connecting the motor to the pump, may be damaged if the starting toque is too high.
some types of compressors need low torque to accelerate to full speed. Reciprocation compressors require high starting torque especially when starting under load. Other types such as centrifugal and axial vane type require low starting torque because of the design characteristics.
The need to limit the inrush current may be due to government mandates, power company restrictions, distribution system limitations, or operation in areas that are adjacent to or within a residential area may need to limit current during starting to eliminate voltage drops that cause light flicker.
A good example of this is on pumps for hydraulic elevators in an apartment complex. These pumps have low starting torque requirements, so limiting current during starting minimizes any line sags that would have occurred if the pump was started direct on line.
Thursday, March 3, 2011
Leakage current detector (RCCB)
The Fault current overloads and short circuits
can be detected by circuit breakers like MCB’s
MCCB’s & HRC Fuses etc. But, Circuit
breakers don’t detect leakage currents, which
are dangerous for humans and livestock and if
not detected can lead to fire hazards. We need
a solution that detects such leakages currents
and disconnects the circuits from the power
supply. Here comes the solution in the form of
RCCB (Residual Current Circuit Breaker) also
known as ELCB (Earth Leakage Circuit
Breaker) which provides protection against
direct and indirect contact of personnel or
livestock and against probable fires.
RCCB works on the principle that in an electrical circuit the incoming current is the same as out
going current as shown in the Diagram. RCCB incorporates a core balance transformer having
primary and secondary windings and a sensitive relay for instantaneous detection of fault signal.
The primary winding lies in series with the supply mains and load. Secondary winding is
Connected to a very sensitive relay. In a faultless situation, the magnetizing effects of the current
carrying conductors cancel each other out. There is no residual magnetic field that could Induce a
voltage in the secondary. During flow of leakage current in the circuit an imbalance is created in
the circuit which gives Rise to leakage flux in the core. This leakage flux generates an electrical
signal that is sensed by the relay and it trips the Mechanism thereby disconnecting the supply.
can be detected by circuit breakers like MCB’s
MCCB’s & HRC Fuses etc. But, Circuit
breakers don’t detect leakage currents, which
are dangerous for humans and livestock and if
not detected can lead to fire hazards. We need
a solution that detects such leakages currents
and disconnects the circuits from the power
supply. Here comes the solution in the form of
RCCB (Residual Current Circuit Breaker) also
known as ELCB (Earth Leakage Circuit
Breaker) which provides protection against
direct and indirect contact of personnel or
livestock and against probable fires.
RCCB works on the principle that in an electrical circuit the incoming current is the same as out
going current as shown in the Diagram. RCCB incorporates a core balance transformer having
primary and secondary windings and a sensitive relay for instantaneous detection of fault signal.
The primary winding lies in series with the supply mains and load. Secondary winding is
Connected to a very sensitive relay. In a faultless situation, the magnetizing effects of the current
carrying conductors cancel each other out. There is no residual magnetic field that could Induce a
voltage in the secondary. During flow of leakage current in the circuit an imbalance is created in
the circuit which gives Rise to leakage flux in the core. This leakage flux generates an electrical
signal that is sensed by the relay and it trips the Mechanism thereby disconnecting the supply.
Wednesday, March 2, 2011
BEE 1961 Motor Control: Venue for test
Venue for test 1 as below:
1) Section E11BB & E12BB: F7 (Lab Analogue)
2) Section E13BB: F8 (Lab Electronic Industry)
Please be punctual.
Good luck
note:
1) study on PPE
2) motor name plate
2) Current transformer
3) etc
1) Section E11BB & E12BB: F7 (Lab Analogue)
2) Section E13BB: F8 (Lab Electronic Industry)
Please be punctual.
Good luck
note:
1) study on PPE
2) motor name plate
2) Current transformer
3) etc
Sunday, February 27, 2011
BEE 1961 Motor Control _Test 1
Test will be held on:
Date: 4-March-2011 (Friday)
Time: 2.30 pm
Venue: will be announced later
Which will cover:
1) Safety
2) Chapter 1: Motor Control ystem
3) Chapter 2: Devices & Component
Date: 4-March-2011 (Friday)
Time: 2.30 pm
Venue: will be announced later
Which will cover:
1) Safety
2) Chapter 1: Motor Control ystem
3) Chapter 2: Devices & Component
Wednesday, February 23, 2011
BEE 1961 Motor Control_new notes & labsheet
Docs below have been uploaded
1) Labsheet for Star-Delta
2) Notes on safety
Please use the same link as previously to be connected to e-notes
1) Labsheet for Star-Delta
2) Notes on safety
Please use the same link as previously to be connected to e-notes
Wednesday, February 9, 2011
Link to e-notes
BEE 1961 Motor Control
click below link for notes & labsheet
http://notes.ump.edu.my/fkee/Noor%20Zaihah%20Jamal/BEE_1961%20Motor%20Control/
You are advised to complete your labsheet before practical session, given 2 hours during lab practically enough for installation.
click below link for notes & labsheet
http://notes.ump.edu.my/fkee/Noor%20Zaihah%20Jamal/BEE_1961%20Motor%20Control/
You are advised to complete your labsheet before practical session, given 2 hours during lab practically enough for installation.
Tuesday, February 8, 2011
Replacement class (section E11BB)
BEE 1961-Motor Control (Section E11BB)
Please be informed that replacement class will be held as below:
Date: 11-Feb-2011 (Friday)
Time: 2.30 - 4.30 pm
Venue: Motor control lab
Please be informed that replacement class will be held as below:
Date: 11-Feb-2011 (Friday)
Time: 2.30 - 4.30 pm
Venue: Motor control lab
Monday, January 17, 2011
Class cancel - announcement on 18 Jan 2011
Dear Student BEE 1961 Motor Control,
Your class as below date will be cancelled.
Section E11BB : 17 Jan 2011
Section E12BB: 19 Jan 2011
Section E13BB: 20 Jan 2011
Please be informed.
Your class as below date will be cancelled.
Section E11BB : 17 Jan 2011
Section E12BB: 19 Jan 2011
Section E13BB: 20 Jan 2011
Please be informed.
Thursday, January 13, 2011
Announcement (13-Jan-2011)
Dear Students BEE 1961,
Please download the attached labsheet for Metering Circuit & bring the hardcopy to the class.
Our next class will be on:
1) Motor protection devices
2) Motor control accessories
3) Metering circuit
Please do some surfing with the googles on the related topics to enhance yr understanding during class.
Good luck!
Please download the attached labsheet for Metering Circuit & bring the hardcopy to the class.
Our next class will be on:
1) Motor protection devices
2) Motor control accessories
3) Metering circuit
Please do some surfing with the googles on the related topics to enhance yr understanding during class.
Good luck!
Monday, January 10, 2011
Monday, August 23, 2010
Basic elect app: project presentation
Dear student DEE 1931 ,
Your project group presentation will be held as below:
Date: 25/08/2010 (Wednesday)
Time:9.00 pm
Venue: as usual
Note:
1) Please bring together your project report
2) 15-20 minutes will be given for each group c/w Q&A session
3) Please make sure that you are well known of your project and any question shall be asked to any of your group member..
so, be prepared..Good luck
Your project group presentation will be held as below:
Date: 25/08/2010 (Wednesday)
Time:9.00 pm
Venue: as usual
Note:
1) Please bring together your project report
2) 15-20 minutes will be given for each group c/w Q&A session
3) Please make sure that you are well known of your project and any question shall be asked to any of your group member..
so, be prepared..Good luck
Monday, August 9, 2010
Basic elect app: project guideline
Dear student DEE 1931,
Please visit below link on project guidelines
http://www.4shared.com/document/lpDqPtp1/PROJECTS_nzj11.html
The report content shall not be limited to this guideline, you may add other info if related.
Please visit below link on project guidelines
http://www.4shared.com/document/lpDqPtp1/PROJECTS_nzj11.html
The report content shall not be limited to this guideline, you may add other info if related.
Wednesday, August 4, 2010
Two way switch
a two way switch have to work in pairs. Above is a simple schematic diagram of how the wiring for a two way switch should be installed.
As mentioned, a two way switch has three terminals, as seen in the diagram, S1 and S2 represents the two switches. In S1 you will notice that the live wire goes to a and then connected to c in the switch. In this case, the b terminal and the c terminal are the common terminals connected by two common wires to the common terminals of S2.
The diagram demonstrate a state where the light are now being switched OFF. Now for example, S1 is installed at one end of the corridor and S2 at the far end. When you enter the corridor, you will switch on the lights using S1. Inside the S1, the terminals are closed via a and c. What happens when you toggle the switch is the copper strip connecting a and c will be pushed to connect to b. That means a and b now forms a closed circuit. Now look at the diagram again.
The live wire from the mains will now go to a connected to c where it is again connected by common wire 2 to b2 of S2 which is the switch at the end of the corridor. This live supply then passes through to b2 to a2 and onwards to the light, thus completing the full loop to light up the light. All this while, S2 has never been touched.
When you walk right to the end of the corridor and you want to switch OFF the light, the switch will toggle the terminal from b2 to c2, breaking the circuit, thereby switching OFF the lights. The switch will stay that way for the whole duration until someone else switches the lights ON again at either end. When that happens the reverse order happens.
Tuesday, August 3, 2010
Basic elect app: notes_4th lab
Basic elect app: Lab cancelled
Dear student DEE 1931,
Your lab as below will be cancelled
Date: 04/08/2010 (Wednesday)
Time: 9.00 am
However, lab on this Thursday is ON as usual.
Your lab as below will be cancelled
Date: 04/08/2010 (Wednesday)
Time: 9.00 am
However, lab on this Thursday is ON as usual.
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