The information provided by this page is technical in nature. Although you may understand the terminology used, there is a big difference between understanding electricity and installing or working on electrical equipment. It is our aim to provide information which will help reduce code violations, fires and electrical accidents. If you are not trained for this type of work and are interested in becoming an electrical worker there are many vocational/technical schools and colleges where you can learn under the supervision of a qualified person. Doing your own work can be dangerous, but if you intend to do the work yourself anyway, our program can help you at least pick the proper materials to use. Tradesman software assumes no responsibility for damages or incidents caused by use of the information provided and recommends that any work performed be by qualified persons and meet all local and national electrical codes. With that said, below are the main features of our ELECTRICIAN program. Click on the features to learn more about them.
System Requirements: IBM Compatible, 256K RAM, Color or Mono, Hard Disk Not Required
Excessive voltage drop can be blamed for many electrical failures. The
code recommends a maximum voltage drop not to exceed 3% for branch circuits.
When this value is exceeded, there may be conditions created that can cause
fires, insulation breakdown and electrical shock hazards. Some not so serious
problems are listed below
Poor lumen output of lighting fixtures
Prolonged locked rotor currents and pre-mature insulation failure in motors
Inadequate output of resistive loads such water heaters, baseboard radiation
and lamps
Overheating of circuit conductors on long circuit runs.
Creation of heat from IR losses in conduits and other enclosures
Failure of motor control relays to pull in due to low voltage conditions
If you need to solve voltage drop problems for circuit designing, troubleshooting or maintenance try solving the question below using your present method. The ELECTRICIAN SOLVES THIS PROBLEM IN LESS THAN ONE SECOND from the time you select the calculate option!
What size copper, THHN insulated wire would you install for a 12 amp, 120 volt single phase load located 200 feet from the circuit breaker and meet the code recommendation of not more than 3% voltage drop?
Voltage drop is only one of the many features in our electrician program.
You just enter the data and select the calculate option. This very accurate
feature will handle most of your circuit calculations for selecting wires
or checking existing installations. You can change any one value and recalculate
without re-entering all the data. If you have been shopping around, you
would see other software companies charging more for voltage drop calculators
than we charge for our entire package!
By the way, the answer, if you want to compare answers, was Number 6
AWG., as illustrated in an actual printout of the calculations shown below.
Notice the asterisk and highlight making it easy for you to select the
correct wire size. The results calculated show all the sizes of wires with
their respective voltage drop, voltage at the load, power line loss and
ampacity! And this is only one feature of the ELECTRICIAN program!
VOLTAGE DROP & WIRE SELECTION
AWG E-load E-drop W-loss Ampacity KCMIL E-load E-drop W-loss Ampacity
| 18 | 81.8 | 38.16| 457 | | | 250 | 119.7| .25 | 3 | 215 |
| 16 | 96 | 23.95| 287 | | | 300 | 119.8| .21 | 2 | 240 |
| 14 | 104.9| 15.07| 180 | 20* | | 350 | 119.8| .18 | 2 | 260 |
| 12 | 110.5| 9.5 | 114 | 25* | | 400 | 119.8| .15 | 1 | 280 |
| 10 | 114.1| 5.95 | 71 | 30 | | 500 | 119.9| .12 | 1 | 320 |
| 8 | 116.3| 3.73 | 44 | 40 | | 600 | 119.9| .1 | 1 | 355 |
| 6*| 117.6| 2.36 | 28 | 55 | | 700 | 119.9| .09 | 1 | 385 |
| 4 | 118.5| 1.48 | 17 | 70 | | 750 | 119.9| .08 | 1 | 400 |
| 3 | 118.8| 1.18 | 14 | 85 | | 800 | 119.9| .08 | 1 | 410 |
| 2 | 119.1| .93 | 11 | 95 | | 900 | 119.9| .07 | 0 | 435 |
| 1 | 119.3| .74 | 8 | 110 | |1000 | 119.9| .06 | 0 | 455 |
| 1/0 | 119.4| .59 | 7 | 125 | |1250 | 119.9| .05 | 0 | 495 |
| 2/0 | 119.5| .46 | 5 | 145 | |1500 | 120 | .04 | 0 | 520 |
| 3/0 | 119.6| .37 | 4 | 165 | |1750 | 120 | .04 | 0 | 545 |
| 4/0 | 119.7| .29 | 3 | 195 | |2000 | 120 | .03 | 0 | 560 |
Size 6 stranded wire meets 3 % (3.6) voltage drop requirement.
12-06-1996
Press a key to continue 20:01:29
When you have to select a conduit or other raceway, you are required by code to not exceed a certain dimension according to Table 1 in the code. When the wires are all the same size and insulation, you can use the tables in appendix C. If the wire sizes and insulations are not all the same, you need to calculate using several tables and charts in the code book. The ELECTRICIAN program lets you enter any combination of wire sizes, insulations and number of wires. The 1996 code made significant changes in the method you now need to use to find the proper size raceway for combinations of wires. Incidentally there are 30 wire sizes and 30 insulations you can use making 900 possible combinations. Multiply that by 12 different raceways and you get 10,800 possible combinations and that doesn't include the different number of wires for each type of wire! It took many hours of tedious data entry to put this data into our program. We even found some errors in the code tables and corrected them for our program. If accuracy is important to you then our program should be what you are looking for.
If you have to size raceways, use your current method to solve the following problem.
What size EMT would you install to carry 4, No. 8 AWG, THHN insulated wires and 4, No. 6 THHN insulated wires? What size nipple could you use for this installation?
Simply select the raceway installer feature, enter your data and select
the view conduits option. You can add different sizes, different insulations
and different numbers of wires. For you experts, the program even calculates
and displays the correct size raceway when note 7 of table one is in effect
(when the decimal is .8 or above).
By the way the answer is 1 1/4 inch EMT for the raceway and 1 inch EMT
for the nipple as shown in an actual printout of the calculation. Notice
all the other sizes are also listed with their respective areas. This output
was designed to allow you an opportunity to select a different size to
compensate for length of run or number of bends. Nipple sizes are not included
in the tables but we put it in our calculation as a convenience for you.
The 40% column is used for the EMT because there are more than two wires.
The 60% column is used for the nipple size.
Electrical Metallic Tubing
8 (Total wires) occupy .3492 Square Inches.
First qualifying trade size is 1 1/4
First qualifying trade size nipple is 1
Size Diam Area 53% 31% 40% 60%
1/2 0.622 0.3038 0.1610 0.0942 0.1215 0.1823
3/4 0.824 0.5333 0.2826 0.1653 0.2133 0.3200
1 1.049 0.8642 0.4580 0.2679 0.3457 0.5185
1 1/4 1.380 1.4957 0.7927 0.4637 0.5983 0.8974
1 1/2 1.610 2.0358 1.0790 0.6311 0.8143 1.2215
2 2.067 3.3555 1.7784 1.0402 1.3422 2.0133
2 1/2 2.731 5.8576 3.1045 1.8159 2.3430 3.5146
3 3.356 8.8455 4.6881 2.7421 3.5382 5.3073
3 1/2 3.834 11.5447 6.1187 3.5788 4.6179 6.9268
4 4.334 14.7521 7.8186 4.5732 5.9009 8.8513
12-06-1996
Press a key to continue 21:03:47
Ambient temperature affects the ability of a wire to carry its rated current. When the temperature around a wire is too high, the insulation can break down and the wire, because of its increased resistance can cause further insulation failure, excessive voltage drop and poor operating performance and efficiency. The code requires adjustment for ambient temperature. Not adjusting for ambient temperature is a code violation.
If you need to adjust the ampacity of a wire because of its operating environment, solve the question below using your current method.
What is the new ampere rating for number 10 copper, THHN insulated wire when it is run in an ambient temperature of 120 degrees F?
This feature calculates ampacity correction for any size wire according
to code tables. There are a lot of wires being installed without considering
operating temperatures and surrounding temperatures. This does not have
to continue. With this feature of the electrician program, you can select
the proper size wire and be sure it meets the ampacity requirements for
the environment it is installed in.
Use this feature to find ambient temperature correction then use the answer
to re-rate the wire ampacity for the number of wires in a raceway for further
reduction, if necessary.
The answer as shown below from an actual printout from the electrician program is 32.8 amps. Keep in mind that the wire is rated for 40 amps but can not be protected at more than 30 amps. Use the 40 amp figure for derating purposes.
AMPACITY & DERATING WIRES - Ambient temperature correction
Wire: CU - TA,TBS,SA,FEP,RHH,THHN,THHW,THW,THWN,XHHW,ZW-2, ETC.
Size: 10 AWG ORIGINAL Rating: 40* AMPS.
(Ambient Temperature) Correction New
Fahrenheit Celsius Factor Ampacity
-----------------------------------------------------
70 - 77 21 - 25 1.04 41.60
78 - 86 26 - 30 1.00 40.00
87 - 95 31 - 35 0.96 38.40
96 - 104 36 - 40 0.91 36.40
105 - 113 41 - 45 0.87 34.80
114 - 122 46 - 50 0.82 32.80
123 - 131 51 - 55 0.76 30.40
132 - 140 56 - 60 0.71 28.40
141 - 158 61 - 70 0.58 23.20
159 - 176 71 - 80 0.41 16.40
* Maximum overcurrent protection is 30 AMPS
A> Do another problem
B> Exit
Press a letter option or highlight your choice and press 12-06-1996
Move highlighting bar with up/down arrows or space bar. 21:52:07
The number of current carrying conductors in a raceway can affect the amount of heat generated inside the raceway. This heat then causes the wires to be subjected to temperatures that can be detrimental to the insulation on the wires. Because of this effect, the ampere rating of the wire is required by code to be reduced. The reduction in ampacity for number of wires in a raceway is in addition to the reduction in ampacity for ambient temperature. In the example used for ambient temperature correction if the number 10 AWG wire was re-rated to 32.8 amps, and it was one of 6 wires in a raceway it would need a further reduction using 32.8 amps as the rating of the wire.
What is the new ampere rating for number 10 copper, THHN insulated wire when it is installed with 5 other conductors in the same raceway?
With this feature of the electrician program, you can select the proper size wire and be sure it meets the ampacity requirements for the number of wires in a raceway. The answer as shown below from an actual printout from the electrician program is 32 amps. Keep in mind that the wire is rated for 40 amps but can not be protected at more than 30 amps. Use the 40 amp figure for derating purposes when there is no additional de-rating for ambient temperature.
AMPACITY & DERATING WIRES - Number of wires in pipe
Wire: CU - TA,TBS,SA,FEP,RHH,THHN,THHW,THW,THWN,XHHW,ZW-2, ETC.
Size: 10 AWG ORIGINAL Rating: 40* AMPS.
Correction New
# of wires Factor Ampacity
-----------------------------------------------------
4 thru 6 80% 32.0
7 thru 9 70% 28.0
10 thru 20 50% 20.0
21 thru 30 45% 18.0
31 thru 40 40% 16.0
41 and above 35% 14.0
* Maximum overcurrent protection is 30 AMPS
A> Do another problem
B> Exit
Press a letter option or highlight your choice and press . 12-12-1996
Move highligting bar with up/down arrows or space bar. 06:54:55
Junction boxes are required to be sized according to the number of wires,
sizes of wires, devices and fittings that are installed in them. Overcrowded
junction boxes lead to damaged insulation, cramped wiring space and difficult
maintenance. Larger devices such as ground fault receptacles have made
it necessary to require more space in junction boxes. The electrician program
allows you to simulate an installation and shows you the proper size metal
box or cubic inches required when using non metallic boxes.
What size Junction box would be required for 1 duplex receptacle and 2
14-2 romex cables installed in a metal new work device box with clamps?
In the above question, you need to allow for six conductors, four for circuit
wires and two more for the duplex outlet. You must also allow one wire
for all the grounding wires and one more wire for the clamps.
JBOX/VOLUME CALCULATOR
Cu. In. Total
Size No. Each Cu. In.
-----------------------------------------------------
A> 18 AWG 0 1.50 0.00
B> 16 AWG 0 1.75 0.00
C> 14 AWG 6 2.00 12.00
D> 12 AWG 0 2.25 0.00
E> 10 AWG 0 2.50 0.00
F> 8 AWG 0 3.00 0.00
G> 6 AWG 0 5.00 0.00
H> Clamps 1 2.00 2.00
I> Stud/Hickey 0 2.00 0.00
J> Grounding Wires 1 2.00 2.00
K> View Jboxes ---------
L> Clear 16.00 Total Cubic Inches
M> Exit
To calculate volume for device yokes, add two wires of the largest size wire
connected to the device. See N.E.C. 370-16 for details.
Press a letter option or highlight your choice and press . 12-12-1996
Move highlighting bar with up/down arrows or space bar. 21:28:37
After entering all data, you simply press the K key to view all the junction
boxes available or just the boxes that meet the volume requirements for
your installation.
JBOX/VOLUME CALCULATOR
Box shape, dimensions and cubic inches Cubic inches Calculated = 16
-------------------------------------------------------------------------------
Rnd. or Oct. 4 x 2 1/8 - 21.5
Square 4 x 1 1/4 ----- 18
Square 4 x 1 1/2 ----- 21
Square 4 x 2 1/8 ----- 30.3
Square 4 11/16 x 1 1/4 25.5
Square 4 11/16 x 1 1/2 29.5
Square 4 11/16 x 2 1/8 42
Device 3 x 2 x 3 1/2 - 18.0 (Ganged 2=36.0 3=54.0 4=72.0 5=90.0 6=108)
Masonry Box/Gang 3 3/4 x 2 x 3 1/2 21.0
FD - Minimum Internal Depth 2 3/8 Single Cover/Gang 18.0
FS - Minimum Internal Depth 1 3/4 Multiple Cover/Gang 18.0
FD - Minimum Internal Depth 2 3/8 Multiple Cover/Gang 24.0
12-12-1996
Press a key to continue 21:35:22
Notice that the only device box meeting your space requirements is a 3
x 2 x 3 1/2 inch deep device box. You can save time and money as well as
meet code requirements by selecting the proper sizes of junction boxes.
The electrician program even shows the device box volumes for ganging up
to six boxes for when you need to put boxes together.
Residential services was put into the electrician program primarily
for calculating demand factors for dwellings. It is not the method of choice
for most installations but clearly demonstrates the method of calculating
the service size for a relatively common house with alternate fuel sources
for heat and hot water. It follows Example 1a in the code. If you need
to calculate service sizes for other loads, we recommend using one of the
other examples in the code book as a guide.
What size conductors should be installed for a 1500 square foot house with
a 12 KW range and a 5.5 KW dryer?
When you enter the information as shown below, you will be shown the load
in amperes to help you select the proper size wire to install.
RESIDENTIAL SERVICES
A> Area in sq. ft. --------------------------- * > 1500
B> Volt Amps (VA)/sq. ft. (normally 3) ------- * > 3
C> Lighting circuit voltage (normally 120) --- * > 120
D> Lighting circuit rating (15 or 20 amps) --- * > 15
E> Small appliance circuits (normally 2) ----- > 2
F> Laundry circuits (normally 1) ------------- > 1
G> Range over 1.75 KW (not over 12 KW = 8000)- > 8000
H> Dryer VA (5000 or nameplate over 5000) ---- > 5500
I> Maximum Service voltage (normally 240) ---- * > 240
J> Compute service
K> Calculator
L> Exit
Press a letter option or highlight your choice and press . 12-12-1996
Move highlighting bar with up/down arrows or space bar. 22:00:45
When you press the J key to calculate you are shown the following data
as produced by the electrician program.
RESIDENTIAL SERVICES
Area in square feet --------------------------------------------- 1500
Total VA lighting load at 3 VA per sq. ft. ---------------------- 4500
Lighting load amperes at 120 volts. ----------------------------- 37.5
Minimum # of 15 ampere lighting circuits. ----------------------- 3
Lighting, small appliance and laundry VA before demand factor --- 9000
Lighting, small appliance and laundry VA after demand factor ---- 5100
Total VA for range and dryer ------------------------------------ 13500
Total VA for range, dryer and demand factor load ---------------- 18600
Service entrance or feeder conductor load (in amps) ------------- 77.5
Neutral load (in amps) ------------------------------------------ 60.625
This calculation follows NEC(R) Chapter 9 Example 1a - One Family Dwelling.
For additional loads, add them as shown in Example 1b.
See NEC(R) 230-79 for minimum ratings for disconnecting means.
Optional calculation methods are provided in NEC(R) Chapter 9.
12-12-1996
Press a key to continue 22:02:48
Ohms Law is one of the most basic formulas used to solve for circuit
characteristics and for trouble shooting and designing circuits. That's
why it is one of the first formulas taught in electrical courses. The electrician
program uses 12 hidden formulas that let you enter any two values of volts,
watts, amps or ohms and automatically calculates the other two unknown
values. In addition, once a calculation is made, the program allows you
to change the voltage to see what would happen when a device is connected
to a circuit with improper voltage or excessive voltage drop. This is a
very handy feature!
What is the amperage drawn by a 1440 watt heater when connected to a 120
volt circuit? How much wattage would be produced if it was accidentally
connected to a 240 volt circuit?
A while back, an electrician made this mistake and according to national
magazines was punished because of the fire that resulted. This did not
have to happen if the concept of doubling the voltage causes a quadrupling
of wattage was fully understood! If there is any doubt about what would
happen on a circuit, let the computer simulate it for you.
OHM'S LAW & POWER
Answers
------------- A> Watts
Watts = 1440 B> Amps
Amps = 12 C> Ohms
Ohms = 10 D> Volts
Volts = 120 E> Clear
F> Exit
Press a letter option or highlight your choice and press . 12-12-1996
Move highlighting bar with up/down arrows or space bar. 22:23:41
Change the voltage to 240 and recalculate and watch the wattage change.
OHM'S LAW & POWER
Answers
------------- A> Watts
Watts = 5760 B> Amps
Amps = 24 C> Ohms
Ohms = 10 D> Volts
Volts = 240 E> Clear
F> Exit
Press a letter option or highlight your choice and press . 12-12-1996
Move highlighting bar with up/down arrows or space bar. 22:25:28
This knowledge or ability to calculate watts, volts, amps or resistance
is often taken too lightly by electrical workers. Failure to calculate
circuit characteristics can cause dangerous installations as well as damage
to electrical components.
A while back an electrician had to put a 120 volt coil on a 240 volt
circuit in an emergency in order for an industrial process to continue.
The electrician needed an understanding of series and parallel circuits
to determine what load to put in series with the coil. Although many electrical
workers think that calculating series and parallel circuit characteristics
is only done in schools and text books, there really is a need for this
skill to be carried into the field. The electrician program lets you solve
these types of problems even if you can't remember the formulas or methods.
Students of electricity should use the program to verify the answers they
get from manual calculations to be certain they have learned the concepts
involved.
What can you put in series with a 120 volt coil that normally draws .5
amps in order to let it operate on a 240 volt circuit?
This is a multi-level question in that you need to find the total resistance
to limit the current to .5 amps on the 240 volt circuit (use ohms law)
then find the difference between the coil resistance and the load to be
placed in series with the coil.
With practice, an understanding of the concepts of series and parallel
circuits an ohms law will make you a better problem solver and more valuable
as an electrical worker.
The answer to the coil problem was to put a 120 volt 60 watt light bulb
in series with the coil to let it operate until a 240 volt coil was installed.
What is the total hot resistance of five 120 volt 100 watt light bulbs?
Hint:
Find the resistance of one bulb using ohms law then use the parallel circuit
calculator to find total resistance. (one bulb = 144 ohms)
SERIES & PARALLEL CIRCUITS - Parallel resistance
COMPONENTS INSTALLED
--------------------
R1 = 144 A> Install
R2 = 144 B> Remove
R3 = 144 C> Change
R4 = 144 D> Clear
R5 = 144 E> Total -> Memory
F> Exit
Total = 28.8 Ohms
Press a letter option or highlight your choice and press . 12-12-1996
Move highlighting bar with up/down arrows or space bar. 22:57:19
This feature of the electrician program lets you perform calculations
beyond the normal features of the program then lets you cut and paste the
answers into the input sections of the normal features. You wont need to
write down and copy information to the program this way. Also the calculator
has constants that are common to electricians for solving three phase circuit
calculations, converting watts to BTUs, finding peak and rms voltages,
etc.
We have a 100% satisfaction guarantee. We have been in business since
1991 and have sold many programs and updates to our customers. To list
them all would just be a waste of computer resources and would bore you.
Here are just a couple of comments from electrician program users.
I have used the ELECTRICIAN program for the last three code cycles,
and have found it to be a valuable teaching aid. The electrical installation
simulator provides the user with a technically accurate, easy to use program
for those in the electrical industry.
Joe Tedesco, NEC Consultant
Since I purchased your program, I can safely say that I have used
it over a hundred times and have saved more hours of research than I care
to think about. You may use this letter as a reference any time you wish
and I will be happy to speak to anyone interested in my opinions and experiences.
Thank you for your help.
Roy Paulin, Electrician
To summarize, if you are looking for a computer program that can take you from beginner to experienced electrical worker, this is a program you should try. No web page is going to simulate the true feeling of our program. As soon as you see how fast and accurately the ELECTRICIAN program solves problems you will not want to be without it. The cost of the electrician is tax deductible for businesses and when spread over a code cycle is less than a 20 cents a day. And if you check out our internet coupon, you can save even more!