1980 r100rt electrical gremlins..

[barryh]

Robs comments about megger insulation testers reminded me of a little story.

Back in 1971 I was a first year Instrument apprentice with ICI. At Christmas time it was the tradition for the whole gang of apprentices which included all the trades, to tour the various trade workshops singing carols in the expectation of being given a contribution of money to our Christmas fund (Apprentices were poorly paid in those days).

At the electricians shop the buggers would megger test us using old hand operated meggers before giving us any money. They made every apprentice hold on to the probes with each hand while they gave it a wind. There was a trick to making sure you didn't get an electric shock and the lads with a knowledge of ohms law knew what to do. A hand cranked megger would normally produce several hundred volts but only if the test resistance was quite high. If you were timid and grasped the probes lightly, your body resistance was high and you got an electric shock. If you grasped the probes firmly the resistance was lower and the megger tester couldn't produce enough voltage to give you a painful shock.

I gripped them tight !

Not much Health and safety in those days eh. Imagine that being allowed today. The Electricians reckoned they were teaching us something which I suppose was true enough.

[mkj]

Unlikely to be the stator but not impossible, my stator did burn out, the replacement solved the problem. I have owned many multi meters none went above 20 kohms.

[Rob Frankham]

Unlikely to be the stator but not impossible, my stator did burn out, the replacement solved the problem. I have owned many multi meters none went above 20 kohms.

Surprised to hear that...

I currently have 4 DVMs of various types from the 'supermarket cheapo' that I throw into the pannier when I'm out on the bike to a Fluke which stays very much at home.

The highest 'Ohm' range varies. The cheap one is 2 Meg, there is an 'Aldi' special that lives in the car which states that it's 200 Meg on the case, my original, an Altai that must be getting on for 50 years old that is 20 Meg and the Fluke auto-ranges up to 40 Meg.... I wouldn't consider a meter with an maximum Ohm range of 20k to be worth buying.

Rob