Quote:
Originally Posted by GeeTwo
The big snap action breakers are rated 40A. The main breaker is rated 120A. If you have four or more snap action breakers in roughly equal use, the main breaker and brown out are more likely to be an issue than an individual breaker. The advantage to having more small motors is that you are more likely running them nearer peak efficiency, and also spreading the waste heat around better.
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You would think this is true, but take a look at the breaker curves. Let's say you have 4 CIMs going at 80 amps each. That's 200% rated current for the 40A breakers, so that's 1.5 to 3.9 seconds. The total is 320 amps, or 267% rated current for the 120A breaker, which is about 7 to 17 seconds. The 40A breakers should go first, assuming your drivetrain is the only thing running.
Does that match teams' real world observations?
Datasheets*:
http://files.andymark.com/PDFs/am-0282_data_sheet.pdf
http://files.andymark.com/MX5SpecSheet.pdf
*Presumably the datasheets for the 40 and 120A breakers on the Andymark website are accurate and up-to-date
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