Previous in Forum: Zune video player and I pod repair   Next in Forum: The World of DC Motors ......
Close
Close
Close
5 comments
Rate Comments: Nested
Participant

Join Date: Sep 2007
Posts: 2

400 cycle busbars

09/25/2007 3:09 PM

Does anyone have information about copper busbar Ampacity when used with 400 cycle power systems?

Register to Reply
Pathfinder Tags: busbars
Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.

"Almost" Good Answers:

Check out these comments that don't yet have enough votes to be "official" good answers and, if you agree with them, vote them!
Commentator

Join Date: Sep 2007
Location: Watertown, SD USA
Posts: 68
Good Answers: 1
#1

Re: 400 cycle busbars

09/25/2007 4:30 PM

Do you have a specific temp rise you are trying to optimize around?

...I assume you are looking for a 'no airflow' continuous rating.

Register to Reply
Power-User

Join Date: Jan 2007
Location: Los Angeles, CA
Posts: 381
Good Answers: 1
#2
In reply to #1

Re: 400 cycle busbars

09/25/2007 6:03 PM

If I remember 300 Hertz has a greater Skin Effect than lower frequencies.

Your Buss Bars can be reduced in size than those carrying lower frequencies.

Gotta be a formulae around here some where?

Register to Reply
Power-User

Join Date: Jan 2007
Location: Berlin (Germany)
Posts: 332
Good Answers: 1
#5
In reply to #2

Re: 400 cycle busbars

09/26/2007 10:19 AM

Sorry, but reducing the SIZE is not completely correct. To lower the skin effect the THICKNESS has to be smaller but the current carrying area = SIZE has to be the same to avoid overheating, so only the SHAPE has to be changed.

Busbars of 600mm² are good for 1000A up to 70°C.
Regards Uwe

__________________
The sum of intelligence on earth is a constant. And the population grows and grows and .....
Register to Reply
Participant

Join Date: Sep 2007
Posts: 2
#3
In reply to #1

Re: 400 cycle busbars

09/25/2007 6:07 PM

My goal is to find or develop a table of continuous busbar Ampacitys for various copper busbar sizes allowing for 60, 75 and 90 degree C maximum temperatures with no forced air flow.

Register to Reply
Anonymous Poster
#4

Re: 400 cycle busbars

09/25/2007 8:56 PM

As for Temp Rise, you can calculate that pretty closely using the following equation: Trise('C)=(Power Loss (watts)/Surface Area)^.833 Power Loss (watts)=I^2*R (Current Squared in Amps* Resistance in Ohms) while Surface Area is the sum of all 4 sides in square mm in the above equation.

As for your resistance, you will have to determine the material used (such as straight copper) it's resistivity per unit area, your total area and actual length.

Skin Depth for 400Hz begins around .14185 inches or can be computed by: 2.837/SQRT(frequency in Hz) So as long as you keep your bus bar thickness below .14185" you will have no skin effect to be concerned about.

Or if you really want to get into it:

http://en.wikipedia.org/wiki/Skin_effect

Register to Reply Score 1 for Good Answer
Register to Reply 5 comments

"Almost" Good Answers:

Check out these comments that don't yet have enough votes to be "official" good answers and, if you agree with them, vote them!
Copy to Clipboard

Users who posted comments:

andymon (1); Anonymous Poster (1); dbdwoods (1); GreenShoes (1); uweka (1)

Previous in Forum: Zune video player and I pod repair   Next in Forum: The World of DC Motors ......

Advertisement