18 Oct
2010
18 Oct
'10
12:17 p.m.
On Sun, 17 Oct 2010, Tony Duell wrote:
OK... That's also said over here, but normally as slang rather than
written in manuals.
Often the 'high beams' are known as
'main beams' over here. As opposed to
'dipped beams/headlights'. The swtich to select between them is the
'dipper switch' or 'dip swtich'. The original (trade?) name for a twin
filamanet headlight bulb was a 'double dipper'.
Incidentally, what word would you generally used for 'dazzled'?
"blinded". Unfortunately, the lack of differentiation between
"flash blindness" and
permanent damage has led to many people believing that thousands of people
have permanently lost their eyesight due to laser pointers.
In USA, it is called a "dimmer switch" and "dual beam", and high
beams are
Interesting...
As I understnad it, the original anti-dazzel device for electric
headlamps was a rheostat (variable resistor) to dim them. This was
replaced by a mechancial dipping system, when you pressed the dipswitch,
the RH (nearest the centre of the road/oncoming traffic) was turned off,
and the LH one was moved mechancially by a solenoid. Then came the
twin-filament design whcih is, of course still used on most cars today.
So the original really was a 'dimmer'.
NEVER called "main", possibly due to the
likelihood that the clueless will
misinterpret that to mean that they should almost ALWAYS be in the "high"
position.
The filaments in a dual beam "sealed beam" headlight are not individually
Sealed beam headlamps (large glass envelope incorporatign the reflector
and front lens) have fallen out of fashion oer here. Most cars have a
reflector/lense assembly (often approximately rectangular) with a
twin-filament bulb inserted from the rear. Often these days it's a
tungsten halgoen bulb. when it fails, you replace just the bulb. But of
course you do have to replace both filaments together.
Actually, my father's current car, a Skoda, has separate tungsten halogen
signle filament buibs for the main and dipped beams. So you only have to
rrplace the filament that's failed.
replaceable. If you can intercept one being
discarded, the use of the
remaining filament makes it a very handy load for power supply testing.
Indeed. Of coruse part-failed twin filamanet bulbs are good for this too.
You normally have to specially order them, but 6V car bulbs are
available. A 6V headlamp bulb will typically have a couple of filaments
rated at 30-odd watts each. Which make ideal loads for large-ish 5V
supplies (put both in parallel for a 10A or so load). The 6% 5W tail lamp
bulb is good for smaller supplies.
The dimmer switch is now on the steering column in a multi-purpose
combination switch that controls enough things that it is not generally
considered to be repairable, in lieu of replaceable.
Sme over here. Actually, most of those multi-function swtiches can be
taken apart, contacts cleaned, etc.
I remember when the dimmer switch was a button for the
left foot.
I;'ve never been in such a car, but I've got plenty of books describing
them. A friend of mine drives a car where the (oriignal equipment)
windscreen washer pump is on the floor, left foot operated.
-tony