HI Dave

On Sun, 18 Nov 2007 21:14:22 +0000 (GMT), "Dave Liquorice"
wrote:

On Sun, 18 Nov 2007 18:05:21 +0000, Adrian wrote:

Earth/neutral swapped on the supply?

Or chiller unit mounted in same truck as genny using the vehical chassis
as the return. Anything not connected to the chassis doesn't have a
circuit...

Nope - wasn't that g
Chiller is ounted in a towable trailer - fed via a cable from the
genny - probably 20m away. Pluggery at that point looked like
the sort of kit you find on 110v isolation transformers - ended up
'somehow' in a conventional square-pin mains socket - extn lead out to
where I was.

Plugging my amp in back at the 3-pin socket on the trailer also failed
to make the amp work...... - which is why I suspected a problem with
the amp....



Thinking about it - I'm not sure just 'what' the geny was using for
'earth'.... no ground spikes that I could see.... don;t know what's
the usual arrangement in these circumstances

In theory the generator chassis should be connected to one of the
alternator phases and that point also connected to the real earth via a
spike. But there are also arguments for having both phases floating wrt
real earth. What is "best" really depends on the individual circumstances,
how things are switched/protected and the existance or not of an RCD.

I guess the real lesson to be learned (regardless of the bit about
outdoor music and divine intervention g) is that, if you can't
supply _all_ the kit yourself, then you need to take along some basic
test kit to debug the other guys supply arrangements....

Should have remembered that from doing disco / band stuff about 35
years ago !

Ah well - another lesson (re-)learned g

Thanks
Adrian