After serious thinking Bill Wright wrote :
Harry Bloomfield wrote:
John Williamson presented the following explanation :
Harry Bloomfield wrote:
Remember the old type charge / discharge ammeters, where used a couple of
turns of cable which used to sometime be fitted to vehicles ? I have one
fitted to the tractor mower which is not marked + and - and I'm sure it
reads the wrong way. The needle goes left when on charge, I seem to
remember the norm is to move to the right.

Can anyone remember, before I take steps to correct it?

My Lard Roller ammeter is marked - to the left, + to the right, as have
all the others I've used. Has your tractor mower been converted from +ve
to -ve earth at some point?

No, it is not that old - I suspect the coil windings (2 turns) were simply
fitted the wrong way and it has bothered me since I got it.

Is it fitted upside down?

Bill

No, someone had wound it the wrong way when the tractor was built :-?

It uses a couple of turns of the main wire feed, wrapped around a metal
bracket at the back of the meter and the wire had a sticky label on it
showing the direction of flow.

I have rewound it so it reads charge with needle moving to the right.

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