On Thu, 18 Jan 2007 10:45:26 +0000, Richard Walker wrote:

Hmmm... Voltage between L&E and N&E is just 85v when no load,
disconnected from the house wiring. Voltage between L&N is 240v.

Off load the rather primative AVR in the alternator will be confused. I
would be at all surprised at odd readings, load it up with a couple of
hundred watts or so and see what happens.

Thought I had a reasonable understanding of electricity, but this has
me puzzled. Should I not connect the generator earth to the house
earth?

No, when the power fails you cannot rely on any of the supply wires to be
what it should be, live, neutral or earth. What you should do is bond the
generator chassis to a local (good) earth spike, bond one of the
generator phases to the chassis and thus the local earth creating a
"neutral" and have an RCD at the generator and run extension cables to
the kit you want to power and plug them in.

It gets very messy and has lots of implications if you want to use the
house wiring direct. Back feeding the main supply *HAS* to be avoided at
all costs, not even the remotest chance of it happening by forgetting to
open a switch somewhere. I do have vauge memories that you do have a
proper break before make change over switch though. If that is the case
the the bonding described above should sort things out but the supply
earth should not really be connected. Hence the RCD as the earth loop
impedance via the local spike will probably be rather high.

--
Cheers
Dave. pam is missing e-mail