Re: Electrical Puzzles - more

["JOHN CLAYTON" <john.h.clayton@domain.elided>]

Peter,

Your original question was perfectly clear to me, so
I was rather puzzled by Glen's reply!

As to an answer, the only clue I have is that the ROM
lists a lower wattage Outer bulb of 37.5 watts for "Other
L.H.dip markets". However this still doesn't account for 
such a big difference in the fuse ratings.

The Haynes manual is very confusing where it lists
bulb wattage. (Page 123 in mine)  
"Headlamp LH dip inner" actually refers to the Mainbeam
bulb. 

Regards,
John Clayton
SOC member 1570.

----------
> From: PGAHOWELLS@domain.elided
> To: gmerrel@domain.elided
> Cc: stag-digest@domain.elided
> Subject: Re: Electrical Puzzles - more
> Date: 26 October 1998 19:51
> 
> Sorry Glen, I didn't word this very well.
> What I am asking is why is it 25 amp fuses for each 55 watt headlamp
bulb, and
> 10 amp fuses for each 55 watt dip lamp bulb. They are the same bulbs
GLB448.
> They all have dedicated wire. Why the difference in fuses?
> Peter H 
> 
> 
> In a message dated 26/10/1998 17:47:06 GMT,  gmerrel@domain.elided
writes:
> 
> << Subj:	 Re: Electrical Puzzles - more
>  Date:	26/10/1998 17:47:06 GMT
>  From:	gmerrel@domain.elided (Glenn Merrell)
>  To:	PGAHOWELLS@domain.elided
>  CC:	stag-digest@domain.elided
>  
>  Hello Peter,
>  	I would hope that the fusing in your fuse block is there to protect the
wire
>  leading from the fuse block to the various accessories. That is the
normal
>  function of a fuse.  Wire current carrying capacity is sized to carry at
> least
>  125% of the maximum current load of the device, and the fuse is (should
be)
>  sized to protect the wire from drawing more current than it is designed
to
> carry
>  before it burns up and catches your car on fire.  This 125% is a minimum
> value
>  for safety.  he wire may be larger.  By adding a larger fuse, you risk
> burning
>  up the wire harness.
>  	The second reason that the fuse is more than four times the actual
operating
>  load amps to the headlights is is different than the initial current
surge
> from
>  the lamps being switched on.  First initial current to an inductive
device
> like
>  a lamp is like a shorted circuit for a millisecond or two.  This initial
>  "inrush" of current is not enough to heat up the fuse to burn it out.  
In
> other
>  words, the wire to the headlights should be sized to carry 125% more
than the
>  rating of the fuse so the fuse breaks before burning up the wire, and
the
> fuse
>  is sized for the full maximum rating of the device.
>  
>  Just some basic electrical standards stuff, not my opinion, and I would
not
>  speculate buy adding more stuff on the circuits.
>  Regards,
>  Glenn  Merrell
>  Triumph Stag Register USA VP
>  
>  "Keep Your Stag Cool, Install a NEW Composite Cowl Today"
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>  
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>  
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>  
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>  Bruce Krobusek, President
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>  
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>  mailto:101714.1343@domain.elided
>  
>  
>  PGAHOWELLS@domain.elided wrote:
>  > 
>  > Hi all
>  > Puzzle 1
>  > Why is there a 25 Amp fuse for each headlamp and a 10 amp fuse for
each dip
>  > lamp.
>  > In UK they are all the same bulbs, 55watt. divide 55 by 12 Volts = 
4.58
> Amps.
>  > Thus 10 amps should be enough for both main and dip.
>  > Puzzle 2
>  > On the cover of the fuse box we see Headlights Main Beam 1
>  > then Headlights Main Beam 2
>  > then Headlight Dip Beam RH
>  > Headlamp Dip Beam LH
>  > Why use a 1 and 2 convention in naming the main beams, and a RH LH
> convention
>  > to name the dip beams?
>  > 
>  > I have just wired in a rear Fog Lamp to my 1971 Car, hence my current
(ha
> ha)
>  > preoccupation with things electrical.
>  > I wired the fog lamp so that it comes on when I put the Master light
Switch
> to
>  > the FOG position. Trouble is the headlights go out because this switch
>  > position is meant for Front Fog lamps. However on the relay board I
have
>  > installed an extra relay powered by the fog lamp wire and this pulls
the
>  > headlamps back in by drawing power from the spare overdrive fuseway to
the
>  > spare blade on the headlamp (Dip) fuseway.
>  > I think it is quite a good arrangement. I hope you do too!
>  > Peter H
>  
>  
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>  Message-ID: <3634B563.2C5D2E37@domain.elided>
>  Date: Mon, 26 Oct 1998 10:46:11 -0700
>  From: Glenn Merrell <gmerrel@domain.elided>
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>  Subject: Re: Electrical Puzzles - more
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