On 17/04/2018 10:55, Graeme wrote:

Back to the Morris.Â* I have an ammeter, 30-0-30, and the dynamo is rated
13.5v, 22 amps.Â* Still +ve earth.Â* What I don't have is suitable brown
cable, and there seems to be a lot of conflicting advice.

Found cable described as 3.0mm² 44/0.30 27.5 Amp, which seems OK, or
should I go for 4.5mm² 65/0.30 35 Amp to be on the safe side?

Any idea of 'standard' car Lucar connector size?Â* Options seem to be
6.3mm, 8mm etc.Â* I'm guessing 6.3, being equivalent to the old 1/4 inch?

Thanks!

The terminals on a Lucas ammeter I have here are 3/8". I suggest you use
6mm cable as a minimum.
Have you considered fitting a digital ammeter? The shunt resistor can be
fitted in a plastic box somewhere where the battery lead doesn't need to
be extended. Then you simply take two (thin) wires to the actual meter,
or to the dividing circuit if the meter needs one. If it does, build the
dividing circuit into a sealed box because otherwise damp affects it
(very high value resistors are involved) and alters the reading. The
meter also needs a supply and a ground. You can take the supply from the
ignition circuit. If you get an illuminated one it's best to select one
rated at 15V, otherwise the little LEDs will burn out prematurely.

Bill