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MG MGA - Fuse Ratings

I can't find any reference in the manual or handbook to the correct fuse ratings for the two fuses in the fusebox. It's a Mk2 (not that makes any difference I believe) so can someone tell me what were the original ratings using the Lucas-type glass fuses which I believe are rated at"failure" current.
Graeme Williams

Graeme
I expect MGA's are typical of that era and, like a Frogeye, are 17 continual & 35 blow.
Alan
Alan Anstead

Both are 35A - as given in the SPL..............Mike
m.j. moore

That's what I would have thought, but the circuit which is permanently live had a 50A fuse. I think it only powers the horn - and that isn't THAT loud!
Couldn't find any reference to this information in manual or handbook.
Thanks Alan and Mike

(My interest comes from needing to put my indicators on the permanently live circuit. Having wired in a suitable switch to operate hazard flashers I realised I would need the key in, which is not a good idea. The advantage of the MGA indicator switch is that it can't be left on, so changing the supply shouldn't be an issue. I will drop the main fuse rating, but I have added another in line fuse for the flashers.)
Graeme Williams

I think you guys better read this:
http://mgaguru.com/mgtech/electric/et102.htm
John.
J Hughes

Thanks John. That item does confirm the 50A for the horn circuit, which seems very high, although there was a twin horn option I believe.
I am aware of the 25/50 ratings issue as, separately, I have been preparing to rewire my Frog. A common mistake people make is to replace a glass 50A fuse with a modern 50A fuse without understanding that the glass Lucas style fuses were rated at "fail" current whereas modern fuses are rated at "running" current. Unfortunately, I am not sure that "all" glass fuses are made according to that original standard of "failure" rating! The consequences could be serious!
Graeme Williams

This thread was discussed between 19/11/2015 and 20/11/2015

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