Notes on Understanding Key Electrical Concepts

SMS Training Review

• The aim is to commit to learning something new every day to enhance confidence and decision-making skills, leading to professional growth.

Committing to Daily Learning

• Commit to learning one new thing each day, regardless of how small it may seem.
• It could be something like understanding the Concur process or the definition of potential difference.
• Focus on fully understanding the topic without any ambiguity.
• Avoid overwhelming yourself by trying to grasp complex topics like the PV process all at once; instead, break it down into smaller, manageable parts.
• In three months, expect a significant increase in confidence in decision-making.
• In six months, anticipate feeling more like a seasoned technician.
• Within a year or two, aim to make decisions and answer questions with the same level of expertise.
• Learning one thing often leads to the discovery of additional related topics.
• This commitment eliminates the need to impress others, as competence will naturally arise from consistent learning.
• It's challenging to find one new thing to learn every day, even with experience.
• Continuously challenge yourself to explore new concepts.

Reminder and Encouragement

• Expect occasional check-ins to discuss what you've learned each day.
• This isn't a test but a reminder to challenge yourself.
• Committing to daily learning leads to becoming a better technician and teammate.

AC vs. DC: Fundamental Differences

• Direct current (DC) travels around the conductor, while alternating current (AC) travels within the conductor.
• The fundamental difference between AC and DC is frequency.
• Frequency gives AC its reactive capability, leading to reactive power.

Reactive Power Explained

• Real power is a function of real and reactive power.
• Analogy: beer glass.
  • Real power (drinkable beer).
  • Reactive power (foam or head).
• In the analogy, real power is represented by the clear liquid beer, which is consumable, while the foam or head represents reactive power, which is necessary to fill the glass but not consumable.
• In power, real power/true power is represented by real and apparent or real and reactive.
• Visualize electrons moving from East to West Coast, with a light bulb (load) at the end.
• Reactive power is the power required to initiate current flow before any work is done.
• In an AC circuit with a frequency of 60 Hz, electrons move back and forth.
• Reactive power is the power needed to start the flow of current and is consumed but doesn't produce light, heat, or mechanical movement.
• Power = Voltage * Current.
  • In DC circuits, this calculation is straightforward.
  • In AC, it involves additional factors, including reactive power.
• Voltage and current can be represented as sinusoidal waveforms.
• Reactive power can be leading or lagging, affecting voltage on the line.
  • Leading reactive power can bolster voltage (e.g., increasing voltage from 250,000 to 252,000 volts).
  • Lagging reactive power (using an inductor) can reduce generation when there's too much on the line.
• Reactive power is like the head on the beer, necessary to fill the line without doing work yet.
• Once the light bulb is on, all the power in the line overcomes the initial reactive component.
• Unlike AC, direct current doesn't have reactive power.

Direct Current Behavior

• In DC, electrons move in unison only when there's a complete circuit with a load.
• DC current is either flowing or not, without the buzzing or frequency of AC.
• This lack of reactive capability in DC means it can't reach across gaps like AC.

Safety Implications

• AC's reactive capability allows it to reach through non-insulated barriers, posing a hazard.
• DC requires a complete circuit to flow, so a barrier (not necessarily insulation) can prevent current flow.
• Example: Touching a 1200-volt DC wire without completing a circuit won't cause harm.
• AC can cause vibration and expansion/contraction at 60 Hz, even without direct contact.
• DC needs a path to flow, and a gap can prevent current flow.

Further Discussion and Clarifications

• The "one thing a day" suggestion is informal and aimed at personal growth, not formal evaluation.
• The goal is to become a subject matter expert (SME) and increase value to the team.

Potential Difference

• The homework is to define potential difference without using the word "voltage."
• Potential difference is a foundational electrical concept.

Learning Strategies and Resources

• Struggling with a concept is acceptable and provides an opportunity for different perspectives.
• The focus is on understanding the truth about DC, especially in an AC-centric environment.
• Knowing why safety measures work is crucial, rather than blindly following rules.
• Applying AC hazard rules to DC can lead to a lack of understanding of actual risks.
• Educate yourself on why certain actions are unsafe, using principles like Watt's Law and Ohm's Law.
• Learning one concept can lead to understanding many related topics.
• Use all available resources, including the internet, to find answers.
• Understanding resources and how to navigate them is more important than memorization.
• Trust your resources over your brain, as brains can make mistakes.
• The Uglies book is recommended as a pocket reference guide for electricians.
• Open-book tests and resource utilization are encouraged for confident decision-making.
• Aim to know things definitively rather than just believing them.
• Learn to navigate problems and figure things out, but don't hesitate to ask for help or consult resources like YouTube.
• Confidence in decision-making breeds safety.

Quizzes and Assessments

• Record quiz slides and take pictures of them to use as a resource because it's hard to navigate back once you start the quiz.
• There are quizzes on the material at the end of some modules, but there are also ones that just require you to attest that you have read the material.
• Don't feel bad about failing quizzes; review the material together before retaking.
• Thinking through answers is more important than just being given the answer.
• Communicate about quiz failures to avoid complications with unlocking attempts.
• It's better to let them know ahead of time so you can figure out the answer together.
• There is no embarrassment from failing a quiz. This is encouragement to do better.
• They are communicating that it's better to let the team member know so they can work together and figure out the material and come to the correct decision together before it's too late.