"Terry Coombs" wrote in message
news
On 5/26/2018 11:53 AM, wrote:
On Sat, 26 May 2018 05:41:56 -0000 (UTC), James Waldby
wrote:

On Fri, 25 May 2018 17:38:09 -0700, etpm wrote:
On Fri, 25 May 2018 08:40:22 -0700 (PDT), "Dave, I can't do that"
wrote:
I have a 1-1/2HP, 220v motor running from the dryer socket, all
good.
...
The house wiring uses the 3-wire 110-0-110 for the 220/240 but
the gen
has three pins for the 240-out. I am guessing one is Ground and
the
others are Neutral and 240v.
...
The reason neutral wires are called that is because they are tied
to
ground in the breaker panel which means there is no potential
voltage
between the neutral wire and the ground wire, at least in the
breaker
panel. So there is no neutral on the generator unless [...]
"The reason neutral wires are called that is because they are tied
to
ground" seems to me to be incorrect. True, in US wiring, neutral
wires
usually have near-ground voltages on them, but more generally a
neutral
wire is one with no current flowing in it when a system is in
balance.
In US wiring the neutral CAN have current running through it.
Eric

In a properly balanced load center that current will be minimized
... so I corrected your statement .

--
Snag

The neutral carries the difference between the hot leg currents. If
the load current is 100A on one leg and 0A on the other the neutral
will carry 100A. Increasing the load on the other leg decreases the
current in the neutral, so with 100A through both hot legs the neutral
carries 0A, not 200A, and it can be the same size cable as the two
hots.

Conceptually you get the right answer if you treat both loops of the
circuit as separate and then add the currents, If the neutral has 100A
flowing in from one hot leg and simultaneously 100A out to the other
they will sum to 0

The relevant circuit analysis principle is that the currents into and
out of a wire junction have to sum to zero, since you can't create or
destroy electrons. A capacitor at the junction doesn't negate this
rule, it turns the solution into a problem in differential calculus
whose answer is an equation of voltage versus time.

The Romans used the same net-sum principle to run an empire-wide
checking system. When a merchant wrote a check for a cargo of wheat in
Egypt the amount was simply deducted from tax payments sent back to
Rome, and when he returned home the merchant had to reimburse the
treasury (or become lion poop). Thus only the heavily guarded tax
shipments were at risk from storms or pirates.
-jsw