Bridge Rectifier Pre-Lab Information Rectifiers are widely used in power supplies that provide the dc voltage necessary. Materials and equipment needed: i. Materials: · One 120/24 V standard transformer · Four diodes 1N4001 · Two 2.2 kΩ resistors · One 100 μF, 50 V electrolytic capacitor (any voltage rating is fine since is simulation only) · One fuse (any rating is fine since is simulation only) ii. Equipment: · Oscilloscope Procedure: 1. Connect the bridge rectifier circuit shown in Figure 1. Notice that no terminal of the transformer secondary is at ground potential (some simulation software will not run if is not connected to the ground, check yours). The input voltage to the bridge, VSEC, is not referenced to ground. In some simulation software the oscilloscope cannot be used to view both the input voltage and the load voltage at the same time. Check your circuit before run the simulation. Compute the expected peak output voltage. Then run the simulation and use a voltmeter to measure VSEC (rms). Use the oscilloscope to measure the peak output voltage (VLOAD) without a filter capacitor. Tabulate all data gathered. Figure 1 2. Connect the 100 μF capacitor in parallel with the load resistor. Measure VLOAD, the peak-to-peak ripple voltage, and the ripple frequency. Tabulate all data gathered and compare the results with and without the filter capacitor. 3. Simulate an open diode in the bridge by removing one diode from the circuit (choose yours). What happens to the output voltage, the ripple voltage and the ripple frequency? Conclusion: Write your detailed conclusion about this lab experiment. Evaluation and Review Questions: a. Compare a bridge rectifier circuit with full-wave rectifier center-tapped circuit which you did before. Which has the higher voltage output? b. Explain how you could measure the ripple frequency to determine if a diode were open in a bridge rectifier circuit. c. What is the maximum dc voltage you could expect to obtain from a transformer with a 12 V (rms) secondary using a bridge circuit with a filter capacitor? Sections Item Description Maximum Marks 1 Bridge rectifier circuit – without filter capacitor Measurements 20 2 Bridge rectifier circuit – with filter capacitor Measurements ripple voltage and frequency 20 3 Simulation of an open diode 20 4 Conclusion 20 5 Evaluation and Review Questions 20 TOTAL MARKS 100 Risk Risk is not just a board game. Risk to the inexperienced project manager often creates fear throughout the team. Risk is a natural part of the project management process. How the project manager, the organization, and the team view risk is a strong indicator as to the success of the project. In the previous lecture we started to talk about risk assessment. It was stated that risk and evaluation need to begin in the proposal stage and continue through to the completion of the project and beyond. There are three primary processes for addressing risk: avoidance, elimination, and acceptance. This i ...

1. Bridge Rectifier
Pre-Lab Information
Rectifiers are widely used in power supplies that provide the dc
voltage necessary.
Materials and equipment needed:
i. Materials:
· One 120/24 V standard transformer
· Four diodes 1N4001
· Two 2.2 kΩ resistors
· One 100 μF, 50 V electrolytic capacitor (any voltage rating is
fine since is simulation only)
· One fuse (any rating is fine since is simulation only)
ii. Equipment:
· Oscilloscope
Procedure:
1. Connect the bridge rectifier circuit shown in Figure 1. Notice
that no terminal of the transformer secondary is at ground
potential (some simulation software will not run if is not
connected to the ground, check yours). The input voltage to the
bridge, VSEC, is not referenced to ground. In some simulation
software the oscilloscope cannot be used to view both the input
voltage and the load voltage at the same time. Check your
circuit before run the simulation. Compute the expected peak
output voltage. Then run the simulation and use a voltmeter to
measure VSEC (rms). Use the oscilloscope to measure the peak
output voltage (VLOAD) without a filter capacitor. Tabulate all
data gathered.
Figure 1
2. Connect the 100 μF capacitor in parallel with the load
resistor. Measure VLOAD, the peak-to-peak ripple voltage, and
the ripple frequency. Tabulate all data gathered and compare the
results with and without the filter capacitor.
3. Simulate an open diode in the bridge by removing one diode

2. from the circuit (choose yours). What happens to the output
voltage, the ripple voltage and the ripple frequency?
Conclusion:
Write your detailed conclusion about this lab experiment.
Evaluation and Review Questions:
a. Compare a bridge rectifier circuit with full-wave rectifier
center-tapped circuit which you did before. Which has the
higher voltage output?
b. Explain how you could measure the ripple frequency to
determine if a diode were open in a bridge rectifier circuit.
c. What is the maximum dc voltage you could expect to obtain
from a transformer with a 12 V (rms) secondary using a bridge
circuit with a filter capacitor?
Sections
Item Description
Maximum Marks
1
Bridge rectifier circuit – without filter capacitor
Measurements
20
2
Bridge rectifier circuit – with filter capacitor
Measurements ripple voltage and frequency
20
3
Simulation of an open diode
20
4
Conclusion
20
5
Evaluation and Review Questions
20
TOTAL MARKS
100

3. Risk
Risk is not just a board game. Risk to the inexperienced project
manager often creates fear throughout the team. Risk is a
natural part of the project management process. How the project
manager, the organization, and the team view risk is a strong
indicator as to the success of the project.
In the previous lecture we started to talk about risk assessment.
It was stated that risk and evaluation need to begin in the
proposal stage and continue through to the completion of the
project and beyond. There are three primary processes for
addressing risk: avoidance, elimination, and acceptance. This is
where are we will focus the majority of this lecture.
Risk is part of moving the project forward. Risk is required for
innovation and creativity—if we are fearful of risk, then risk
will control us. If we do not take risks, we can quickly become
obsolete. A project is not usually taken on to maintain the status
quo but to advance some part of the operation or organization.
Addressing risk is a critical part of effective project
management. The PMBOK addresses an entire section on risk
including assessment and management. This is highly
recommended reading for this class and in the field. The process
the project manager and their team use to address risk can have
a significant impact on results throughout the project including
the final product.
Risk avoidance: this might seem like the most logical approach
to addressing risk on any project. As was stated earlier, risk
assessment should begin in the proposal stage and continued
throughout the life of the project and beyond. There are many
learning opportunities that present themselves throughout the
life of a project. A proactive approach and assessing potential
risks throughout the project is an excellent way to identify and
address risk in a manner that planning will offer over a reactive
approach. If a project manager identifies a risk such as a critical
component that is being manufactured by a vendor overseas that

4. must be delivered by certain point in the project, there are steps
that can be taken to minimize this risk. Risk avoidance should
include a discussion about the use of a foreign manufacturer or
developing other resources. Risk mitigation strategies should
be used that would lower the potential threat to the project. An
overseas vendor could encounter political unrest, labor issues,
or logistical challenges such as severe storms that prevents the
product from being delivered on time.
Risk avoidance as a result of effective risk management
includes rating the severity of the threat to the project and
organization. By identifying the threat and assessing its
potential, the project manager in their team can develop
alternatives that are more viable than the proposed threat. A
measured approach can determine if the return on accepting the
risk is greater than the risk itself.
Risk elimination: the term means what it says. Can the risk be
eliminated altogether? Microsoft prides itself on creating at
least three ways to do any task regarding any Office software
application. This is an excellent strategy as different
personalities are using different tools for different reasons. If
there are multiple approaches for completing the same task, the
risk of failure and the risk of success are greatly altered. The
same is true in assessing risk for potential elimination while
determining if there are other reasonable alternatives that
involve a less risk for a similar return. If the risk can be
eliminated altogether and still produce a high rate of success,
then this process is likely the best route. Thorough and
comprehensive assessment can greatly diminish the potential
threat to the project.
Several years ago the Toyota Motor Company experienced a
major challenge when one of its vendors could not provide a
key component to a seat belt mechanism that was used on
several models. At the time Toyota had one vendor that
developed these mechanisms. As a result of this failure several
production lines were shutdown which caused Toyota and
several other vendors to lose revenue, large amounts of revenue.

5. Toyota looked at this process and determined that a change was
necessary. The company has since cross trained multiple
vendors to produce different components, thereby eliminating
future risk by having only one producer of a product. This also
resulted in driving down the cost of different components as
vendors can compete for the majority contract.
Eliminating all risk is not usually an acceptable option. An
organization and the project manager must be willing to
acknowledge risk as a key part of a project. Managing risk is a
big part of effective project management. Developing the tools
to assess and address risk is a critical part of the process. Those
that assess the risk but never address the risk by developing
resources and alternatives have lost the value of risk
assessment. Organizations that have a set process for all
projects must create the value for this process or be willing to
accept the consequences. The rationale that: “we’ve always had
done it this way” is no longer valid. A project manager must be
willing to innovate and develop creative solutions in order to
minimize potential risk and threats to the project and thereby
the organization.
Risk acceptance is not going along with the flow. A
comprehensive assessment is necessary for all potential risks.
New risks will present themselves throughout the life of a
project. A project manager will not be able to determine all
risks from project startup. The process must be on going. As
such, there must be a process for continuous assessment and
impact on the project and the organization. A risk management
team is extremely beneficial to ascertain the risk of a project
and to determine whether the risk is worth the potential return.
A project manager that has successfully led a project will be
willing to accept a certain amount of risk. If the project
manager and the risk management team have deemed that the
process they wish to follow requires a component be available,
they have chosen to accept the risk that is associated with this
decision. An effective project manager will still develop
alternative options if this component does not pan out. Risk

6. acceptance does not mean failure to plan alternatives. Risk
acceptance establishes that the risk is been acknowledged and
the decision has been made to move forward with full
comprehension of potential consequences and returns.
What we have addressed in this lecture is not an exhaustive
discussion of how risk impacts a project but is more of an
overview. It is important to be able to thoroughly assess risk
throughout the life of the project. If the assessment tools are
not used in the feedback followed upon this provides an even
increased risk to the project and the overall organization. Risk
should not be taken on due to ignorance or negligence. A
calculated and measured approach to addressing risks is
essential to becoming an effective and a successful project
manager.
Recommended Reading/Videos
· ADP Resource
Risk: http://www.youtube.com/watch?v=gU_w__cvU0E&feature
=results_video&playnext=1&list=PLE8D7D2932997EF27
· Simplilearn: Project Risk Management, Identify Risks, PMP
Certification
Training:http://www.youtube.com/watch?v=7YVCud9BARA
· How To Plot Project Management
Risk: http://www.youtube.com/watch?v=D3S6kpBlDbk&feature
=related
· Risk Management | What is Risk
Management: http://www.youtube.com/watch?v=x8cQKj-
muis&feature=related
· Perform Qualitative
Risk: http://www.youtube.com/watch?v=NsY1IK0gny0
· Simplilearn: Perform Qualitative Risk Analysis, PMP Training
Courses:http://www.youtube.com/watch?v=hzxlmgCk9Yc&featu
re=results_main&playnext=1&list=PL0E546264842ABA2E
· Simplilearn: Perform Quantitative Risk Analysis, PMP Online
Certification
Training:http://www.youtube.com/watch?v=RzWyA7G-qEw
· Risk Management "Fun @ the Grand

7. Canyon": http://www.youtube.com/watch?v=sPBYXuqITKg
· Sims, S. (2012). Qualitative vs. Quantitative Risk Assessment.
Retreived on July 31, 2012
from http://www.sans.edu/research/leadership-
laboratory/article/risk-assessment