General Information

Equipment

You will need to purchase two notebooks. These should be either 4 x 4 or 5 x 5 quadrille ruled. Details on notebook requirements will be given at the first meeting of the lab. Also, the textbook used for EECE 519, Electrical Circuits and Controls, will make a good reference for a number of the experiments.

Lab Room: Rathbone Hall, Room 33. This is in the basement or lower level of the north part of Rathbone Hall. You can get to the basement by going down the elevator from the lobby area, by stairway at the north entrance, or by stairway on the east side.

Lab Hours: You must attend your assigned lab period.

Grade

Grade is to be determined by:

Lab performance.

The instructor will normally circulate around the room during the lab period, asking penetrating questions and observing who is doing what kind of work. An inadequate knowledge of what is going on, letting the lab partner do all the work, blowing fuses, collecting data in a sloppy and disorganized fashion and not asking for help when you need it are all negative factors. Please do not answer questions the instructor is asking someone else. You will get your chance.

The instructor will assign a grade on lab performance at the end of the semester based on the above factors. This grade is separate from homework and the lab notebook grades and will count for up to 30 percent of the total grade, depending on the instructor. This grade will seem more subjective to the student than grades in formal lecture courses, but, like evaluating a performance on a piano, there is really no completely objective way of doing it.

Before tearing down the last lab activity, call the instructor over and have him check your collected data for correctness and completion. Once satisfied you have done all the work, he will initial your notebook.

Lab notebook.

After the lab period is over you should perform any post lab activities called for in the experiment. These will be recorded in the notebook immediately following the data collected during the lab. This notebook will be turned in the following lab period with the homework for that lab. During this lab period you will work in the second notebook, since the first one has been turned in for grading. At the third lab you turn in the second notebook for grading and get the first one back for collecting data for that experiment. This cycle will then repeat for the duration of the semester.

General Rules

KEEP WORK AREAS CLEAN AND NEAT. Components and leads will drop on the floor occasionally but pick them up, even if you are not responsible. There is no excuse for STEPPING ON DROPPED COMPONENTS OR LEADS. RETURN LEADS AND OTHER EQUIPMENT where they belong when through.
NO DRINKS, FOOD OR TOBACCO PRODUCTS are allowed in the lab.
ACADEMIC HONESTY - EECE Department rules apply. Although experiments will require working with a partner and discussion of problems between students is encouraged, copying other students' work is prohibited. Students are expected to perform the laboratory experiments themselves with the minimum help from the instructor.
There is no excuse for ABUSE OF EQUIPMENT. Treat the equipment with respect and care. You may easily have $3000 worth of equipment in front of you. Seemingly trivial items may cost more than you expect. You are held liable for damages resulting from abuse or lack of care. The following are considered abuses: forcing (and, of course, hitting) switches, forcing oversize leads into sockets, yanking leads out of equipment, etc.
STATIONARY SPOTS on CRT's of oscilloscopes can burn brown spots on the phosphor screen. Either reduce the intensity of the spot, or easier yet, keep the spot sweeping. Once the oscilloscope is turned on, it should be left on until the experiment is finished.
THE GROUND OF ELECTRONIC INSTRUMENTS means ground (common reference) potential and shall not be connected to any other potential points. Furthermore, when connecting and disconnecting electronic instruments, the ground shall be the FIRST CONNECTED and the LAST DISCONNECTED.
5-WAY BINDING POSTS, although supposedly designed to accommodate alligator clips, suffer from chewing action when so used. Thus, in order to keep binding posts looking fresh, you are asked to use a stackable metal banana plug or attach scrap bare wire onto which alligator clips can be secured.

Safety Requirements

Safe practices and procedures are of the utmost importance in the Energy Systems Laboratory. Students are required to read, acknowledge and at all times obey all safety procedures within the laboratory.

Attached you will find a listing of the minimum safety practices which must be practiced in the laboratory at all times. These are only the basic safety practice requirements. Additional instructions and information will be necessary from time to time.

Each student must read the attached material and retain it for his or her future reference as necessary. As a condition of utilizing the lab, each student must acknowledge receipt of a copy of the attached material. Further, each student must indicate that he or she has read the material.

Your cooperation and attention to these safety procedures are expected and appreciated. The precautions are for your protection, and that of others.

Failure to abide by these requirements may result in appropriate disciplinary action, including but not limited to forfeiture of the privilege of entering and using the electric machines laboratory.

Please complete, as necessary, and sign the attached acknowledgment set forth below. After signing this memo, return it to your instructor immediately. The following material concerning safety is for your retention.

Email address:

Code for grade posting:

Acknowledgment (click here for a one-page form to print)

I, ___________________________________________, am a student/user of the Energy Systems Laboratory (RA 31 and 33) at Kansas State University. I acknowledge receipt of a copy of the following:

Safety Tips for Energy Systems Laboratory,

Safety Alert on Hazardous Conditions Related to Soft Contact Lenses,

The Fatal Current, and

Fire

I further acknowledge that I have read the same and that I have had an opportunity to ask questions regarding any parts of same which were unclear to me. I have also read the Safety Rules and Suggestions from the EECE 589 Laboratory book written by Dr. Johnson. I agree to abide by the requirements set forth for safe practices in the laboratory.

________________________________________
Student/User

Date: _________________________

Safety Tips for Energy Systems Laboratory

Do not energize a circuit before it is checked by the instructor.
Never handle live circuits.
If anything in a circuit has to be changed, de-energize the circuit first.
Do not touch any insulated part of an energized circuit, unless it is absolutely necessary.
Always make connections from the load toward the source of power. Connect the power source last.
Disconnect the source of power first.
Always install a circuit breaker between the source and all loads or circuits.
Check current connections to make certain they are tight. Loose connections can be dangerous as well as giving erroneous experimental results.
Never open a circuit to change the current range.
Never open the secondary of a current transformer if the primary is energized.
Disconnect the clip end of the potential leads when changing meter ranges of volt meters.
Set rheostats for minimum current (i.e., maximum resistance) before energizing the circuit (Except for special cases such as shunt motor field rheostats!).
Always set autotransformers to minimum output voltage before switching them on.
Do not allow leads to lie on the ground.
Do not allow leads to touch rotating parts.
Keep neckties, loose clothing, etc., away from rotating parts.
Make sure that clutches are always covered by a plastic hood.
Assume that capacitors are charged. Discharge them through a resistance before removal from storage and before disconnecting from a circuit.
Check if a bench is grounded before making any connection on it.
Avoid exposing your eyes to an electric arc (see next section).

Safety Alert on Hazardous Conditions Related to Soft Contact Lenses

Case Histories:

At Duquesne Light Company, a worker threw an electrical switch into a closed position which produced short-lived sparking.
At UPS Inc., and employee raised the colored visor of his welding shield to position a welding rod. He inadvertently struck the metal to be welded, producing an arc.

Both men in the above cases were wearing soft contact lenses. When they attempted to remove the contact lenses later that day, the cornea of each eye was removed with the lens. The result was permanent blindness.

An electric arc generates microwaves that instantly dry up the fluid between the eye and the contact lens, causing the cornea to be bonded to the contact lens. This trauma is painless and the individual never knows an injury has occurred until removing the contacts. Loss of the cornea results in permanent blindness.

This phenomenon was not known prior to these accidents; thus, there are no Federal or State safety and health agency regulations on the matter. The appropriate agencies are pursuing the investigation with zeal.

Since an electrical arc is not an unusual occurrence in the Energy Systems Laboratory (RA 31 and 33), students are warned not to wear soft or hard contact lenses when performing experiments in this laboratory! More information about the contact lens safety can be found at http://www.aclm.org.uk/ by clicking under the "news" link, and at http://www.amweld.org/amwelder/7-00/contact.html. You can find the statements at http://www.aclm.org.uk/ and click the "news" link. The statement is about 75% down the page. The American Welding Society's page dealing with this issue is at the following address:

Fire

The student should become familiar with the location of the fire extinguishers that are located in the laboratory and with their method of operation.

In Case of Fire:

Pull the fire alarm
Call Extension 9-911 (The telephone is in RA 31).

Electric Shock, Illness or Injuries:

Call Security, 9-911. Call Health Services, Ext: 2-6544.

Give a description of the illness or the injury. If an ambulance is needed, advise, and the nearest one will be called.

Safety Rules and Suggestions

Freedom from preventable accidents is an important measure of the foresight and capability of supervision in the engineering industries. The student should give thought to the subject of accident prevention early in his or her training. He or she should prepare mentally to recognize and avoid dangerous situations, and to cope with emergencies. A set of rules cannot be made to apply to all situations. The student should develop the ability to analyze a particular situation. An engineer's reputation for reliability is seriously injured if his lack of foresight results in injury to himself, associates, or equipment.

Haste causes many accidents. Work deliberately and carefully. Verify your work as you go along. Good planning before coming to the laboratory will promote safety.
When working on live electrical apparatus, use only one hand as far as practical, keeping the other hand disengaged from circuitry. All power circuits are dangerous. Adjustment of energized circuits should be made with caution. Do not permit any part of your body to complete a circuit.
Close power switches quickly and positively. Hesitant closing may result in an electric arc. Burns from an electric arc may be severe and slow-healing. You can depend on the circuit breakers and fuses in the circuit to prevent over-currents.
Be careful to keep watch bands, rings, necklaces, and other metallic objects out of contact with live parts when working around electrical apparatus. It is a good idea to remove watches with metal bands while working in the laboratory.
Long hair should be "up" when working around rotating machinery. Likewise, loose clothing, neckties, etc. should be avoided around rotating machinery.
Make sure the banana plugs fit snugly in their sockets. Sometimes they get old and worn so that they slide out too easily. Never splice two banana cords together so that electrically "hot" metal is exposed on the bench. There are a number of banana sockets on the bench which can be used if splicing is necessary.
If any banana jack connectors are loose on their cords, or if any sockets are loose, report immediately to the lab instructor.
Never connect leads so that they hang above rotating parts of equipment. Use leads long enough to have some slack. Avoid long, unsupported spans.
When wiring a circuit, always connect to the source of power as the last step. When disassembling a circuit, disconnect from the power source as the first step.

The Fatal Current

Offhand, it would seem that a shock of 10,000 volts would be more deadly than one of 100 volts. This is not necessarily so! Individuals have been electrocuted by appliances using ordinary house voltages of 120 volts and by electrical apparatus in industry using as little as 42 volts direct current. The real measure of a shock's intensity lies in the amount of current forced through the body, and not the voltage.

Current equals voltage divided by resistance (I = V/R), but the resistance of the human body varies so widely it is impossible to state that one voltage is "dangerous" and another is "safe".

The actual resistance of the body varies depending upon the condition of the skin at the points of contact (moist or dry). The skin resistance may vary from 1000 ohms for wet skin to over 500,000 ohms for dry skin. However, once the skin is broken through (for example by the burning away of skin) the body presents no more than 500 ohms resistance to the applied voltage.

The path through the body has much to do with the shock danger. A current passing from finger to elbow through the arm may produce only a painful shock, but that same current passing from hand to hand or from hand to foot may well be fatal.

Therefore, the practices of using only one hand (keeping one hand in your pocket) while working on high-voltage circuits and of standing or sitting on an insulating material are good safety habits.

The Physiological Effect Of Electric Shock

Electric current damages the body in three different ways:

(1) it harms or interferes with proper functioning of the nervous system and heart,

(2) it subjects the body to intense heat, and

(3) it causes the muscles to contract.

Table 1 shows the physiological effect of various currents. Note that voltage is not a consideration. Although it takes a voltage to cause current, the amount of shock current will vary, depending on the body resistance between the points of contact. It should be realized that the table is based on average values and individual responses will vary.

TABLE 1: Physiological Effect of Current

CURRENT IN AMPS .............. EFFECTS 0.001-0.002 ................... Threshold of Sensation 0.005-0.010 ................... Mild Sensation 0.010-0.020 ................... Painful 0.020-0.040 ................... Muscle Paralysis 0.040-0.060 ................... Severe Shock 0.060-0.100 ................... Breathing Stops 0.100-0.200 ................... Almost Certain Death 0.200-0.500 ................... Breathing Stops 0.5 or more ................... Severe Burns

As shown in the table, shock is relatively more severe as the current rises. At values as low as 20 mA (milliamperes), breathing becomes labored, finally ceasing completely even at values below 75 mA.

As the current approaches 100 mA, ventricular fibrillation of the heart occurs - an uncoordinated twitching of the walls of the heart's ventricles.

Above 200 mA, the muscular contractions are so severe that the heart is forcibly clamped during the shock. This clamping protects the heart from going into ventricular fibrillation, and the victim's chances for survival are improved. However, there will certainly be other effects, depending upon the current level and duration of the shock, as shown in Table 1.

Alternating current (AC) is said to be four to five times more dangerous than direct current (DC). For one thing, AC causes more severe muscular contractions. For another, it stimulates sweating that lowers the value of the skin's resistance. Along that line, it is important to note that resistance goes down rapidly with continued contact. The sweating and the burning away of the skin oils and even the skin itself account for this. That is why it is extremely important to free the victim from contact with the source of current as quickly as possible before the climbing current reaches the fibrillation-inducing level. However, do not touch the person until the electric power is turned off. You cannot help by becoming a second victim. The victim should be attended to immediately by a person trained in CPR (cardiopulmonary resuscitation). Also an ambulance should be called immediately.

The effect of ac on the human body changes with frequency. Unfortunately, 60 Hz is in the most harmful range. At 60 Hz, as little as 25 volts can kill. On the other hand, people have withstood 40,000 volts at a frequency of 1 MHz without fatal effects.

A very small current can produce a lethal electric shock. Any current over 10 mA will result in serious shock.

In Case Of Accident

An ambulance can be called from the adjoining room (RA 31) by dialing 9-911. Be sure to tell the 911 operator that the accident occurred in the basement of Rathbone Hall, Room 33, and that someone will meet the ambulance on the north side of Durland/Rathbone Hall.

The Laboratory Notebook

The technical notebook is one of the basic tools for any experimental work, whether it be basic research, product development, or engineering design. It is primarily for the experimenter's own use, but another person with similar technical background should be able to understand and duplicate any experiment, data, and conclusion, or to prepare a technical report by following only the lab notebook details.

There are many reasons to keep an accurate and complete record of experimental work. Among these are:

To establish the authenticity of the work.
To defend patents.
To act as a basis for technical reports and articles.
To avoid duplication of effort.
To avoid repetition of erroneous procedures.

The nature of the work and the purpose of the experimenter will influence the content and format of the laboratory notebook. Many companies have rigid internal requirements tailored to their specific needs. The notebook formats which follow should not be interpreted as "industry standards". Rather, they are intended to suit laboratory work in the EECE Department, and provide experience in following some acceptable format.

The laboratory notebook must answer the following questions:

WHAT WAS DONE? This includes the approach to the problem or project, as well as the experimental procedure. If tests are conducted on some device, clearly identify that device and give theoretical or nameplate characteristics. Include wiring diagrams and identify measurement equipment. Do not waste space with trivial or obvious details, but give essential steps. Put the title of the experiment at the beginning of the write-up for each experiment.
WHO DID IT? List all members of the lab group, including yourself, at the beginning of the write-up for each experiment.
WHEN WAS IT DONE? It must be obvious to any reader when the experimental work was performed. Put the date at the beginning of the write-up for each experiment.
WHAT WERE THE RESULTS? Data must be distinguished from calculated values. It should be obvious which meter yielded which data. Examples of each type of calculation must be given. Graphs must have titles, and labels and scales are required for both axes. Axes should be drawn with a straight edge, but the curves themselves may be freehanded. It is not essential to match squares on the oscilloscope screen with squares on the paper in your notebook as long as the curve has the proper shape and points of interest such as zero crossings and maximum values are labeled on both axes. Do not recopy data in your notebook. It should be taken neatly the first time.
WHAT DOES IT MEAN? Make observations and draw conclusions from the results of your work. Be precise and concise. Compare your results to the theoretical ones. State specifically why you believe or disbelieve the results? Discuss errors relative to the accuracy of the measuring equipment. This conclusion will normally be at least half a page long and should be in good English, i.e. complete sentences, correct spelling, concise, etc. If English is not your strong suit, you may want to polish your conclusion on scratch paper and copy it in your notebook. If you have a word processor you are welcome to type the conclusion and staple it in your notebook.

Some specific elements are expected in laboratory notebook reports (and may effect your grade) these include:

Experiment title
Experiment date
Names of group members
Equipment list and identification
Statement of purpose of experiment
Experimental procedure
Wiring diagrams
Plots of data observed in lab (neat, complete, and clearly labeled)
Table of data acquired in lab (neat, complete, and clearly identified)
Calculation examples
Discussion of results
Answers to "Discussion and Calculations" section questions
Answers to "Conclusion" section questions

Notebook Formats

There are at least two major formats for laboratory notebooks. The one which will be used in this course is called the Technical Diary. The other format is sometimes called the Informal Lab Report. Both have their place in undergraduate education and in the engineering world. The emphasis in this course is more on learning experimental techniques than on report writing, so the Technical Diary fits this course better.

Technical Diary
The general format and content requirements given above must be met, but the detailed organization of this type of format is left to the experimenter. Wiring diagrams, equipment lists, procedures, data, and calculations are blended together logically and chronologically to form a "blow-by-blow" diary describing the lab work. Observations and conclusions are entered as they are made, and summarized at the end of a coherent section. This format is well suited to research or to experimentation where intermediate results influence subsequent procedures.

Informal Lab Report
Organization of this type of format is more rigid than for the Technical Diary. It is well suited to experiments where the procedure is well established and the general nature of the results can be predicted. This format typically includes objectives (the major goals of the experiment), preliminary (how you intend to achieve the objectives), equipment list and wiring diagrams, procedure (how the experiment was conducted, in sufficient detail to not require a Lab Manual to reproduce), data (in tabular form wherever possible), calculations and results (with one example of each calculation worked in detail), and conclusions.