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Re: What is H3,H4, etc
I picked this up on the Swedishbricks mailing list yesterday. It may
enlighten (ahem) you a bit.
- peter, email@example.com, issaquah, wa -
98 volvo v70 t5 - 5-speed
94 acura legend gs - 6-speed...
Date: Thu, 04 Sep 1997 09:16:47 -0400 (EDT)
From: "John Binford (703) 695-7580" <firstname.lastname@example.org>
Subject: Euro Headlights vs US Spec...NHTSA response
"John Binford (703) 695-7580" <email@example.com> via
SWEDISHBRICKS@SHORE.NET writes :
To those of you that are interested in this sort of thing...I wrote an
to jere medlin at nhtsa regarding euro spec lights vs the miserable us
and got this back:
"The U.S. beam pattern offers significant advantages to drivers in the
must drive at much higher speeds in traffic, and with less stationary
lighting than European drivers. The quantity of light emitted by the
European lamps is essentially the same,. The European lamp on lower
the light aimed closer to the front of the vehicle and spread to the
e, while the U.S. pattern is focussed further down the road, is less
generally more intense to give greater seeing distance for the higher
at we travel in traffic.
The H4 bulb that you like is available in the U.S. as the HB2 (trade
03). It is essentially identical, but has tighter tolerances in the
s associated with the filament locations and the fit of the bulb in the
mp's socket. It is used on many headlamps that are on U.S., European
nese vehicles sold in the U.S. It is archaic, however, relative to
S., European and Japanese headlighting technology. The World vehicle
s striving for new higher efficiency bulbs and many single filament and
ilament bulbs have been or are being developed to meet the needs of
esigners. The H1 bulb has been replaced by the higher accuracy H7 both
nd in Europe. The H7 was designed especially for headlamps with the
lements designed into the reflector rather than the lens. These
d very precisely located filaments in order to properly perform. There
so two new high precision single filament bulbs called the HIR1 and HIR2
e no's. 9011 and 9012) that are higher output and much more energy
hat are intended for these same kind of headlamps. The bulbs use
a-red reflective coatings to achieve much higher light flux with less
by reflecting the significant infra-red energy back at the filament.
ere are three new bulbs that utilize high intensity discharge arc
y are the 9500, the D2S and the D2R. These achieve more than twice the
lux of existing bulbs while using about one third the energy.
Additionally, my agency recently completed a significant milestone in
g toward a globally harmonized beam pattern. Through a process called
ory negotiation, NHTSA invited members of the world vehicle and lighting
tries, international vehicle and lighting organizations, safety
state highway officials and others to participate in a formal
cess to change the U.S. beam pattern to be capable of being
aimed. In doing so, the beam pattern demands about twice as much light
the road as it used to require and must be about twenty degrees wider.
ttern is virtually identical to the beams patterns the are achieved by
dlamps on the 1995 Toyota Camry and the 1995 GM AstroVan. The Toyota
, made by North American Lighting, Farmington MI is one that rated the
in a Car and Driver subjective headlamp performance appraisal reported
While the improved pattern tends to look more like a European pattern
nd more even), it is aimed much higher (further down the road) than a
beam. However, the changes accomplished and now implemented in U.S.
e this beam pattern capable of being used in headlamp designs that would
pable of being legal in all countries that accept U.S. or European beam
ns. In four weeks, I will formally propose to the United Nations in
at the European beam pattern be modified to achieve this higher
d to make this amended beam pattern the basis for an internationally
d standard throughout the World.
The new bulbs mentioned above as well as the HB3 and HB4 (9005 and 9006,
ctively) must be used to achieve this performance. Bulbs like the
the HB1 (9004) are not capable of providing the amount of light flux
. The HB5 (9007) is marginally capable of achieving that performance.
dual filament light source being jointly developed by U.S., European and
ese bulb manufacturers, and intended to have much higher performance, is
to being standardized and within a year will likely be proposed to be
rated in national and international regulations. The heyday of the H4
So hang onto your wallets, troops, cuz we're going to get harmonized.
that mean one single US/Euro/rest of world standard for right hand of
But doesn't it do your heart good to hear that we get significant
the Euro spec, notwithstanding the general universal desire for Euro
lights on our US Brix? This is truly listening to the voice of the