Feild coil E3L

So,on my BSA B33, 12V converted DVR2 , my battery must got quite low as I left the light on for a bit, the next time I rode my mate said the brake light stopped working half way on our ride,, the battery wasn't much chop, so in went a new slightly bigger one, but I fried my dynamo, pretty sure the feild coil has gone, I am fitting new one today, I will check the ohms. But should the regulator, stopped this?, I had a spare dvr2, and swapped it in but no charge. Anyway see what happens. Cheers

Don’t use a headlight bigger than 60 watt.

The field coil should ohm out around 2-3 ohms. I would also check that the armature hasn't fried as well. You can do a quick test by using an ohm meter and probing the commutator. You should have continuity all the way around. It's not foolproof. Finding someone with a growler will give you the true test. If there's a short in the armature, the growler will find it.

bmepkid said:

The field coil should ohm out around 2-3 ohms. I would also check that the armature hasn't fried as well. You can do a quick test by using an ohm meter and probing the commutator. You should have continuity all the way around. It's not foolproof. Finding someone with a growler will give you the true test. If there's a short in the armature, the growler will find it.

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Is that ohm reading for a 6v or 12v?

6vdc. 12vdc coils are generally around 4-5 ohms.

I had previously replaced the armature, on the E3L and must have swapped the brush and feild wire i:e it probably would have worked if the rotation was the opposite direction, I changed two leads around and it's all good. I checked a new 12v feild coil and the one that was in it, one measured 13.1 the other 12.6 ohm, quality multi meter on each end of the wires Cheers
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