Author Topic: E3L field coil connections  (Read 130 times)

Online mikeb

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E3L field coil connections
« on: 27.03. 2021 00:52 »
re an older E3LM (20013) off the B -
the lucas service sheet says the field coil lead with a yellow sleeve must be connected to the earth. I've also seen reference to the green wire.
But both my field coil leads are black, even when cleaned etc.
I think I took adequate notes on disassembly, but just checking: does this matter if one flashes the windings?
if it matters - then how to tell which without colour codes?

thanks
New Zealand
'61 Super Rocket  - '47 B33 -  '18 Triumph Street Triple RS

Online groily

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Re: E3L field coil connections
« Reply #1 on: 27.03. 2021 07:15 »
It does matter mike, yes, as which way round they go affects the direction of rotation.

The easiest way, I find, to ensure rotation (and polarity) are as required is to hook D and one F lead together, and motor it with a battery using your chosen earth.
If it turns the way it is driven on the bike - clockwise it should be atop an MO1 on a B - then all's well and good. And the polarity will be confirmed.
You can do the same by driving the dyn with a drill or lathe and seeing with a meter which way it generates, and what polarity, but I find a battery quicker and easier.

If it turns the 'wrong way', either swap the F leads round, or swap the brush connections over, between D and earth. Whichever offers the more comfortable life for the various wires. Not both though - or you're back where you started.

Never a bad idea to mark one of the F wires for the next time with a bit of something, and to scribe the brush-holder insulating plate with a D or an E to remind you which side is which with the F wires as you have now got them.
Bill

Online mikeb

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Re: E3L field coil connections
« Reply #2 on: 27.03. 2021 08:51 »
Thanks Groily - that's very helpful. I think i noted which way they go (by their differing terminal shapes) tho will check as you described.
cheers
New Zealand
'61 Super Rocket  - '47 B33 -  '18 Triumph Street Triple RS