Volt meter which wire

[JaneHibbert]

I was lucky enough today to have been given a new volt meter and wanted to fit it. now i have read this article -

http://mgaguru.com/mgtech/electric/et220.htm

and following his advice:

You could otherwise connect the volt meter closer to the main battery cable for a lttle better reading of actual battery charging or discharging condition. When using a generator with external voltage regulator you could connect the volt meter at the point where the dynamo output wire connects to the control box. This will be intimately close to the heavy battery supply wire, but will be switched off of the battery circuit when parked (by the control box cut-out relay). Making this meter connection away from the ignition switch (or fuse box) can reduce meter fluctuations caused by small momentary current draws, such as the ticking fuel pump. However, if the dynamo output should fail, the control box cut-out relay will disconnect the "D" terminal from the battery, and the volt meter would no longer be reading battery voltage.

my question is which wire on the diagram on that web page IS the dynamo output wire. and is he saying that if attached to that wire the volt meter WILL shut off when the engine is switched off?

[bmcecosse]

Blimey - I've never heard of that idea. Seems to me you will get silly high readings - certainly just after starting the engine and the dynamo is running hard to pump amps back into the battery. I would simply connect it to a green wire - IGN switched and fused - and earth. Personally - I think it's a fairly useless gauge - but not as useless as a vacuum gauge - or a clock - or a rev 'counter'.......

[JaneHibbert]

i can see why a vacuum gauge might be useless.. but a clock is always handy (one with its own battery) but why would a rev counter be useless handy to set tick over and stuff isnt it?

[bmcecosse]

I have a clock on my wrist......and idle is set by ear......not by a (probably) highly inaccurate rev 'counter'.

[M25VAN]

Don't forget the temp gauge in your finger tips. Long touch, cool. Quick touch, pretty hot. Wish I hadn't done that touch, @#$&ing hot.

[lambrettalad]

also being long sighted,i find a quick glance at a clock on the dash is much quicker and safer than peering at a wrist watch ,after finding my glasses etc

my other name is Mr Magoo 8>(