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by SamBam 748 days ago
I still don't really get the overlapping tolerances, though, because each resistor is not a range, it's a single value that's somewhere in that tolerance.

He says about the cables:

> Each size of cable had a max/min rating that just overlapped it’s neighbor above and below, so every required value was covered by one or more cable.

So that means if you needed a "size 12" cable you could pick a size 10 OR a size 15, and they would both work.

But if you need a 12ohm resistor, it's possible that neither the 10 nor the 15 might work, because the 10 could be a 9 and the 15 could be a 17. So I don't really see how it connects.

To put it another way, what if we had 1000% error tolerances? Could we then get away with just a 1ohm. 1000ohm and 1Mohm resistors, because their tolerances overlap? Obviously not, so I don't see how it relates.

1 comments

Each resistor in the design is a range. The designer picks the tolerance to use, some resistors will be fine with a 10% tolerance, others only with a 2% or 1% tolerance.

Also each resistor is a range, not a single value, since each resistor changes value with temperature & other environmental factors (though temperature is the biggest). That variation is (for normal resistors) less than the tolerance range.