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[jefrs]

An armature is the moving part of a solenoid, the iron rod in this case. As noted though, this alternator is well able to power them. They should not burn out, except they were infamous for burning out. They have a mass thus it will take a given amount of power to lift them against gravity, newton metres per seconds aka watts, and that's without the lamp. Not a lot but I doubt the system is anything like 100% efficient, enough to give an old school 6VDC bike system a hiccup, not this 12VDC one. The DC resistance will not give the current draw because the electro-magnetic coil is being made to do work, the power dissipation will be higher; this is immaterial as there is more than enough juice on hand. The easiest way to get their current draw for fusing purposes would be to stick the ammeter in line and fire them up.

My 'ornithopter' post was made at 4am and I kinda like good steam punk.

[Scalyback]

[center]

"Kinda like good steam punk"?


Try this out, I took this in Paris this summer!

[Count Johnny]

"Count Johnny, I was intrigued to see on the Performance Classics FB page that you went for the same ignition system on Slo Poke that I have on mine."


I did, Adrian. You have excellent taste in this respect.

[jefrs]

Hmm, good steam punk - some steam punk artists haven't got an engineering bone in them. If you're going to do it then it should look as if it works or at least serves a purpose otherwise you just get a 3D metal collage. Acetylene lamps not candles, please.

[Dennis C]

Jefrs, Congratulations you have succeeded in leaving me (and probably others) totally confused once again.

Whilst I agree that it is permissible to call the iron core of a solenoid the armature it is in most cases referred to as the "plunger or piston", the confusion arises partly because you stated "Yes, the armatures burn out if the power is kept on too long", which of course made me think that you were referring to the coil of the solenoid, by your later definition of armature it is pretty darned impossible to burn out the iron plunger.

Incidentally the plunger of the solenoid is weighted to counterbalance the weight of the arm so reducing the power needed to lift it, this was the main reason for them remaining at half mast or similar after use, it took very little neglect or indeed wind resistance to stop them folding away.

[Adrian]

Does anyone here remember Wilf Lunn? That French thing puts me in mind of some of his stuff. A.

[Count Johnny]

Yes. He was on the Vision On programme, wasn't he?

[jefrs]

Dennis C - sorry to cause confusion. Of course I should have said "the coil burns out ..." I suppose the term armature varies (several meanings) whether it is in a solenoid motor (internal to the coil) or that of a relay (generally external), or rotary motor. When my old dad was (amongst other things) making solenoid motors for GEC, it was called called an armature, that being the correct term, the coil being the solenoid; hence calling the entire solenoid motor an armature assembly, probably to avoid confusion with a relay switch.

[scotty]

Scaleback off topic but you seem to know all things electrical how do I test to see if there is current drain from plus side of battery with ign off. Have a good christmas and a happy enfielding new year.

[Scalyback]

Scotty, take an ammeter or multimeter, set for milliamps,



disconnect positive lead from the battery.

connect the positive wire of the ammeter to the positive battery terminal

connect the negative wire of the ammeter to the lead you took off the battery.


you should have a zero reading at the meter's lowest amps (milliamps) range. anything else than zero indicates that current is leaking.



DO NOT touch the bike frame or any other metal part of the bike with the meter leads, this could damage the meter. also, do not turn anything on as this will probably do the same.