"Sparks" wrote in message ...
"BigWallop" wrote in message
...
"Sparks" wrote in message
...
Ello ;-)
snipped
Ha Ha Ha !!!! Sorry. But I've got to laugh. Can I ask who told you
this
is going to work ? For one thing, what feeds your consumer unit after
your
swap over switch ?
There will be some tails from the transfer switch!
The transfer switch is a double pole three position switch (break before
make)
In position 1 (mains) the L and N from the CU are connected to the mains
via
this switch
position 2 is all off
position 3 (Generator) is L and N from the CU is connected to the
generator.
So the L and N (red phase and black phase) from the generator will be
connected to the transfer switch directly and the generator earth will be
kept as a safety earth device as it should be then.
The two earth points will be separate entities, but bonded together as a
common earth in case of faults occurring when either supply is used.
There is no neutral on a generator supply, so how are you isolating the
phase / phase supply from the generator so that it doesn't back feed to
the
existing domestic mains supply ?
The transfer switch does this
But because there is no neutral on the generator, then you'd have to connect
the phase/phase supply from the generator directly to the transfer switch.
Why do you think that one phase from the generator needs to be stuck in the
earth beside the generator unit ?
Sticking one phase from the generator into
the ground, would also mean you'd also have to stick the neutral side of
the
existing consumer unit into the ground. This won't give you full 240
volts
supply unless the earth impedance is below 1 ohm between your generator
neutral/earth point and your consumer unit neutral terminal.
When on generator power...
The L of the generator is connected to the L of the CU (Via the transfer
switch)
The N if the generator is connected to the N and the E of the CU, again
via
the transfer switch
The E does not go through this break before make transfer switch, so is
always connected
But there is no neutral on a generator supply. A generator supplies two
phases that are 180 degrees out of phase with each other. On a 240 volts
generator that means you have 120 volts on the black phase and 120 volts on
the red phase, when added together they give the full 240 volts ac supply.
The earth connection is for safety on the generator in case you touch
anything over to short the phases out.
The question I have, is, the transfer switch manual says there should be
an
earth rod next to the generator
For safety on the generator supply only. Without an earth you stand a
chance of shorting out the phases and not killing the supply by tripping the
generator ELCB (RCD) device.
I already have an earth supplied by the electric company
Which is at, or very, very close to neutral potential. Mainly because the
neutral on the domestic supply is another earth.
will having two earthing points cause a problem?
Not if you connect the two as one bonded system. When on either generator
or the domestic mains supply, the earth would be supplied by both the
generator earth point and the domestic mains head supply connection.
The only safest way to swap between domestic supply and a generator
supply,
is with a proper 100 ampere break before make switch. Like the ones
with
the big handle you'd see on an old Frankenstein movie. Does the unit
you've
bought have an automatic contactor which is rated at 100 amps and has
the
ability to completely break from the domestic supply before it makes
contact
with the generator ? If it does, then you don't have to stick anything
in
the ground and you can leave it as a safety device. You'd only have to
make
the connections from the phase/phase supply of the generator to the
existing
consumer unit, but through the swap over switch.
This is what the transfer switch is all about 
Then the transfer switch would also be supplied by the black phase and the
red phase from the generator as well. But this can cause problems with
appliances that contain capacitative loads. Because the generator supply
doesn't contain a neutral (Zero Potential), there is also a danger of
appliances which use single phase switching, like light switches, not to be
fully isolated from one of the phases (normally black), so this means you
could still short out a load of 120 volts to earth when running from the
generator supply.
Have a word with the sparks that comes to remove the consumer fuse. He
may
have a better idea of what's needed.
Good luck with it.
Thanks!
You're welcome.
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