Hello,

I've bought a small inverter to try out and the instructions talk
about earthing the metal case. I assume the earth pin of the plug is
also connected to the case inside the inverter?

If you use it in a vehicle, you are supposed to connect the earth to
the vehicle chassis. Since a car has four rubber wheels and rubber is
an insulator, what good will this do?

It says that if you install the inverter in a permanent location to
connect the earth to an earth rod buried a metre into the ground.
However it also says that the battery negative should be connected to
this too. Why is that?

It doesn't mention anything about the 240v neutral so do you think
this is connected to earth internally or will the output be floating?

Thanks,
Stephen.

Stephen wrote:
I've bought a small inverter to try out and the instructions talk
about earthing the metal case. I assume the earth pin of the plug is
also connected to the case inside the inverter?
Most likely.

If you use it in a vehicle, you are supposed to connect the earth to
the vehicle chassis. Since a car has four rubber wheels and rubber is
an insulator, what good will this do?
You won't get an electric shock if you touch both the chassis and a
faulty device connected to the inverter.

It says that if you install the inverter in a permanent location to
connect the earth to an earth rod buried a metre into the ground.
However it also says that the battery negative should be connected to
this too. Why is that?
To avoid a potential difference between the inverter and the battery as
there will be a large current flowing and the contacts may be bad.

It doesn't mention anything about the 240v neutral so do you think
this is connected to earth internally or will the output be floating?
It could be either.

Best,
Wolf

"Stephen" wrote in message
...
Hello,

I've bought a small inverter to try out and the instructions talk
about earthing the metal case. I assume the earth pin of the plug is
also connected to the case inside the inverter?

It should be.

If you use it in a vehicle, you are supposed to connect the earth to
the vehicle chassis. Since a car has four rubber wheels and rubber is
an insulator, what good will this do?

you think you have problems think about boats that are floating on water



It says that if you install the inverter in a permanent location to
connect the earth to an earth rod buried a metre into the ground.
However it also says that the battery negative should be connected to
this too. Why is that?

A battery would float, so you could get a largish current flowing
between 'earths'


It doesn't mention anything about the 240v neutral so do you think
this is connected to earth internally or will the output be floating?

From what I understand the Earth and neutral are connected together at power
stations
and tyhat the neutral can float a couple of volts about earth.
I think the idea of earth is more of a safety feature as it's not used for
anything else.

whisky-dave was thinking very hard :
From what I understand the Earth and neutral are connected together at power
stations
and tyhat the neutral can float a couple of volts about earth.
I think the idea of earth is more of a safety feature as it's not used for
anything else.

The earth is connected to neutral at your local sub-station and /or
(depending on your supply system) at your own meter. There is no
neutral as such at the generator or the power station, only the three
phases referenced to earth.

--
Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk

whisky-dave wrote:

If you use it in a vehicle, you are supposed to connect the earth to
the vehicle chassis. Since a car has four rubber wheels and rubber is
an insulator, what good will this do?

I think you'll find carbon-rich tyre rubber conducts passably.

you think you have problems think about boats that are floating on water

Fresh or salt?


It says that if you install the inverter in a permanent location to
connect the earth to an earth rod buried a metre into the ground.
However it also says that the battery negative should be connected to
this too. Why is that?

A battery would float, so you could get a largish current flowing
between 'earths'

Batteries are far too heavy to float. What? Oh _electrically_ :P

Andy