scott thompson
Senior Member
- Location
- Anaheim, California
Re: number of current carrying cond.
Hey-low (hello) there everyone
Bob;
***D'OHH!!!***
The question is:
* If a Spaceship lands in your Back Yard, how many Buckets of Sand does it take to fill a Doghouse... True or False.
</font>
Sorry, I couldn't resist that one!
(Feable attempt at humor...)
Seriously though, I just wanted to post these basic derating examples in this thread, since Current Carrying Conductors and Circuit Derating was the topic of discussion.
It's kind of an FYI thing - and to generate some additional discussions.
Pierre;
Reactive loads (not Pure Resistance only) will result in the Common Grounded Conductor carrying load currents.
Along with this, add Harmonic Distortion to the picture and the Common Grounded Conductor becomes very much a Load Current Carrying Conductor - like as much as 200% of the highest load value found on the Ungrounded Conductors.
Since the percentage of 3 and 4 Wire Multiwire Circuits on Wye systems will be driving "Non-Linear Loads" (Reactive), I decided to show Derating examples reflecting this type of design.
Also, per the LCL Derating factors, I hoped this would be taken into consideration by the individual per scenario.
So for the sake of keeping it simple, let's just assume the loads will be run for 179 Minutes, turned off at 179 Minutes, left off for 30 Minutes, turned back on again for 179 Minutes, turned back off again - left off for 30 Minutes, turned on again for 179 Minutes, (Repeat for eternity)...
Now the full circuit value may be applied as shown in the examples.
Thanks for the replies!
Scott35
p.s. edited summ variee bad spell-leeng!
[ March 08, 2004, 09:11 PM: Message edited by: scott thompson ]
Hey-low (hello) there everyone
Bob;
Oops, my bad!
***D'OHH!!!***
The question is:
* If a Spaceship lands in your Back Yard, how many Buckets of Sand does it take to fill a Doghouse... True or False.
</font>
- <font size="2" face="Verdana, Helvetica, sans-serif">If Snowing only,</font>
- <font size="2" face="Verdana, Helvetica, sans-serif">Saturday,</font>
- <font size="2" face="Verdana, Helvetica, sans-serif">Remove one Egg,</font>
- <font size="2" face="Verdana, Helvetica, sans-serif">If Tempstring >= Run$ then B$ = "X"</font>
Sorry, I couldn't resist that one!
(Feable attempt at humor...)
Seriously though, I just wanted to post these basic derating examples in this thread, since Current Carrying Conductors and Circuit Derating was the topic of discussion.
It's kind of an FYI thing - and to generate some additional discussions.
Pierre;
In the 3? 4W Wye system, it's only this way under certain circumstances - when loads are Pure Resistance only. If all loads were Pure Resistance and of equal magnitude, this will result in almost zero load current on the Common Grounded Conductor for an L-L-L-C Wye connection.
Reactive loads (not Pure Resistance only) will result in the Common Grounded Conductor carrying load currents.
Along with this, add Harmonic Distortion to the picture and the Common Grounded Conductor becomes very much a Load Current Carrying Conductor - like as much as 200% of the highest load value found on the Ungrounded Conductors.
Since the percentage of 3 and 4 Wire Multiwire Circuits on Wye systems will be driving "Non-Linear Loads" (Reactive), I decided to show Derating examples reflecting this type of design.
Also, per the LCL Derating factors, I hoped this would be taken into consideration by the individual per scenario.
So for the sake of keeping it simple, let's just assume the loads will be run for 179 Minutes, turned off at 179 Minutes, left off for 30 Minutes, turned back on again for 179 Minutes, turned back off again - left off for 30 Minutes, turned on again for 179 Minutes, (Repeat for eternity)...
Now the full circuit value may be applied as shown in the examples.
Thanks for the replies!
Scott35
p.s. edited summ variee bad spell-leeng!
[ March 08, 2004, 09:11 PM: Message edited by: scott thompson ]