Ammeter indications

[trevinoz]

It is positive earth so the positive probe should be connected to earth to get the correct polarity reading.

[chaterlea25]

Hi All.
Do not rely on a voltmeter when checking dynamo output...
Connect D an F together and onto one side of a 12v headlamp bulb, and connect the other side to the dynamo body,
Start the engine or mains drill and spin the dynamo in the driven direction.
The bulb should light and brighten with more revs if all is good..
Battery drills are not fast enough to fire up the dynamo..
If the dynamo is off the bike, connect a battery in place of the bulb, D+F and dump body.. the dynamo should motor in the driven direction.. if it turns the opposite direction, swop either the field or brush connections. Not both

John

[Triton Thrasher]

Another variable is direction of rotation.

It is reversed by swapping either the brush connections or the field coil connections.

[bakerlonglegs]

Thank you all for your replies!

It is positive earth so the positive probe should be connected to earth to get the correct polarity reading.

Oh! That makes sense. The dynamo is working then. Time to recheck connections and the DVR2.