Line 32: | Line 32: | ||
==Calculating Wire Sizes== | ==Calculating Wire Sizes== | ||
Assumptions made: | '''Assumptions made:''' | ||
# copper wire resistivity = 11.2 | # copper wire resistivity = 11.2 | ||
# 3% loss from wires | # 3% loss from wires | ||
# allowable voltage drop = 0.36V | # allowable voltage drop = 0.36V | ||
#* 12V system, 3% (0.03) wire loss -> 12V x 0.03 = 0.36V | #* 12V system, 3% (0.03) wire loss -> 12V x 0.03 = 0.36V | ||
'''Variable Declarations:''' | |||
-''A<sub>n</sub>:'' circular mil area | |||
-''n'': AWG | |||
-''m'': AWG | |||
-''Conductor resistivity'': constant, 11.2 | |||
-''Current'': current through wire in Amps, acquired from table | |||
-''Roundtrip (RT) wire length'': complete length of wire, ft, acquired from table | |||
-''Allowable voltage drop'': voltage drop through wires, V | |||
{{How to | {{How to | ||
Line 42: | Line 58: | ||
|header1= Equation | |header1= Equation | ||
|header2= Step # | |header2= Step # | ||
|pics= | |pics= | ||
|size= | |size= | ||
|File:1 wireloss.png|Caption |1 |The equation to the left (Eqn. 1) was used, rearranged, and iterated on to produce the above table. | |File:1 wireloss.png|Caption |1 |The equation to the left (Eqn. 1) was used, rearranged, and iterated on to produce the above table. | ||
|File:2 wireloss.png|Caption |2 |Algebraically rearrange Eqn. 1 to solve for n. The resulting equation is Eqn. 2 to the left. | |File:2 wireloss.png|Caption |2 |Algebraically rearrange Eqn. 1 to solve for n. The resulting equation is Eqn. 2 to the left. | ||
|File:6 wireloss. | |File:6 wireloss.png|Caption |3 |If n<0, replace n with 1-m in Eqn. 1 . | ||
|File:5 wireloss. | |File:5 wireloss.png|Caption |4 |Substituting n=1-m into Eqn. 1 yields this equation (Eqn. 3). Use Eqn. 3 if n<0. | ||
|File:3 wireloss.png|Caption |5 |Solve Eqn. 3 for m, the resulting equation (Eqn. 4) is to the left. | |File:3 wireloss.png|Caption |5 |Solve Eqn. 3 for m, the resulting equation (Eqn. 4) is to the left. | ||
|File:4 wireloss.png|Caption |6 |Eqn. 3 is also a rearrangement of Eqn. 1. Use Eqn. 4 to solve for A<sub>n</sub> | |File:4 wireloss.png|Caption |6 |Eqn. 3 is also a rearrangement of Eqn. 1. Use Eqn. 4 to solve for A<sub>n</sub> |
Revision as of 19:36, 18 January 2020
Introduction
Describe wire length, voltage loss, etc. here.
Tables
The following table shows the American Wire Gauge (AWG) size for several different round trip (RT) wire lengths based on maximum current (A) for a 12V DC system (assuming 3% maximum wire loss):
RT length | 5A | 10A | 15A | 20A | 25A | 30A | 40A | 50A |
---|---|---|---|---|---|---|---|---|
15 ft | 16 | 12 | 10 | 10 | 8 | 8 | 6 | 6 |
20 ft | 14 | 12 | 10 | 8 | 8 | 6 | 6 | 4 |
25 ft | 14 | 10 | 8 | 8 | 6 | 6 | 4 | 4 |
30 ft | 12 | 10 | 8 | 6 | 6 | 4 | 4 | 2 |
40 ft | 12 | 8 | 6 | 6 | 4 | 4 | 2 | 2 |
50 ft | 10 | 8 | 6 | 4 | 4 | 2 | 2 | 1 |
60 ft | 10 | 6 | 4 | 4 | 2 | 2 | 1 | 1/0 |
70 ft | 8 | 6 | 4 | 2 | 2 | 2 | 1/0 | 2/0 |
80 ft | 8 | 6 | 4 | 2 | 2 | 1 | 1/0 | 2/0 |
90 ft | 8 | 4 | 2 | 2 | 1 | 1/0 | 2/0 | 3/0 |
This table was adapted from https://www.engineeringtoolbox.com/amps-wire-gauge-d_730.html .
Calculating Wire Sizes
Assumptions made:
- copper wire resistivity = 11.2
- 3% loss from wires
- allowable voltage drop = 0.36V
- 12V system, 3% (0.03) wire loss -> 12V x 0.03 = 0.36V
Variable Declarations:
-An: circular mil area
-n: AWG
-m: AWG
-Conductor resistivity: constant, 11.2
-Current: current through wire in Amps, acquired from table
-Roundtrip (RT) wire length: complete length of wire, ft, acquired from table
-Allowable voltage drop: voltage drop through wires, V
See Help:Tables.
Use help:references to see how to use the reference format.[1]
Use Help:Images on how to upload the graph image(s). Please remember to use a very descriptive name for the file.
References
- ↑ It is quite easy and just relies on ref and /ref in between less than and greater than symbols.