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Art Todesco

wrote:
On Nov 27, 2:15 am, "Kevin" wrote:
I just finished wiring in two 220V circuits to the shop -- 1 for the dust
collector (5.5A), and the other for the tablesaw (14.5A), jointer (6.5A),
and tbd.

Just for grins I put all of them onto the one circuit. So 5.5+14.5+6.5 =
26.5A. The 20A breaker did not trip. I even tried starting up the tablesaw
while the others were running.

Now in practice, I will keep my dust collector (5.5A, 1.5HP) on it's own
circuit, but apparently I could concurrently run both the tablesaw (14.5A)
and the jointer (6.5A) and possibly even a 3rd TBD on that other circuit.
How is that? The real load must be under 20A, or the 20A breaker allows
more like 28A.

I first tried the TS and Jointer, and when they did not trip the breaker
(total 21A), I added the DC. I was surprised all three did not trip the
breaker. But I guess each was running with no load, so that is surely
another reason.

Curious,

Those ratings are for machines with a maximum work load. In other
words, a saw just spinning doesn't pull as many amps as one ripping a
big piece of wood. If you put them to work instead of just spinning
them up, your results would be different.
Also, breakers don't trip instantly.
They can take quite a long time for
a marginal overload. BTW, for a big
overload, like a short, they trip
pretty fast.