Date: Mon, 23 Mar 2009 19:03:57 -0400
Reply-To: David Beierl <dbeierl@ATTGLOBAL.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: David Beierl <dbeierl@ATTGLOBAL.NET>
Subject: Re: Updated Tail Lamps
In-Reply-To: <20090323220043.0E6121165C2@hamburg.alientech.net>
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At 06:00 PM 3/23/2009, Mike S wrote:
>1) Current FMVSS don't apply to our older vehicles, which are
>grandfathered. I don't see any reference in 108 (
>http://edocket.access.gpo.gov/cfr_2004/octqtr/49cfr571.108.htm ) to
>"candlepower," "cp," or "ratio." Perhaps you can provide a more
>specific citation?
The ratios were my own calculation based on the range btw minimum
tail : maximum stop and maximum tail : minimum stop. Other than
that...from the same URL:
> S5.1.1.6 Instead of the photometric values specified in Table 1 of
>SAE Standards J222*December 1970, or J585e September 1977, a parking
>lamp or tail lamp, respectively, shall meet the minimum percentage
>specified in Figure 1a of the corresponding minimum allowable value
>specified in Figure 1b. The maximum candlepower output of a parking lamp
>shall not exceed that prescribed in Figure 1b, or of a taillamp, that
>prescribed in Figure 1b at H or above. If the sum of the percentages of
>the minimum candlepower measured at the test points is not less than
>that specified for each group listed in Figure 1c, a parking lamp or
>taillamp is not required to meet the minimum photometric value at each
>test point specified in SAE Standards J222 or J585e respectively.
* [my addition] J222 incorporates by reference (or similar wording)
J585d and J586c for tail and stop respectively.
>2) 80 cp sounds way to high as a minimum for a stop bulb. The 1156
>is a common US stop light bulb, and puts out 32 CP.
I thought so too, but look at the values they allow for front turn
signals that are near headlights! Could it be a mistake in
units? Note that U,D,L,R,H in the figures mean Up, Down, Left,
Right, Horizontal. As I understand it, Figure 1a refers to fixtures,
whereas 1b refers to the actual lamps.
> Figure 1a--Required Percentages of Minimum
> Candlepower of Figure 1b
>----------------------------------------------------------------------------------------------------------------
>
>Turn
> Test points
> (deg) signal Stop
> Parking Tail
>----------------------------------------------------------------------------------------------------------------
>10U, 10D................................. 5L,
>5R....................... 20 20 20 20
>5U, 5D................................... 20L,
>20R..................... 12.5 12.5 10 15
> 10L,
> 10R..................... 37.5 37.5 20 40
>
>V............................ 87.5 87.5 70 90
>H........................................ 10L,
>10R..................... 50 50 35 40
>
>[[Page 274]]
>
>
> 5L,
> 5R....................... 100 100 90 100
>
>V............................ 100 100 100 100
>----------------------------------------------------------------------------------------------------------------
>Note--Minimum design candlepower requirements are determined by
>multiplying the percentages given in this Figure
by the minimum allowable candlepower values in Figure 1b. The
resulting values shall be truncated after one
> digit to the right of the decimal point.
>
>
> Figure 1b--Minimum and Maximum Allowable Candlepower Values
>------------------------------------------------------------------------
> Lighted sections
> Lamp ----------------------------------
> 1 2 3
>------------------------------------------------------------------------
>Stop................................. 80/300 95/360 110/420
>Tail \1\............................. 2/18 3.5/20 5.0/25
>Parking \2\.......................... 4.0/125
>Red turn signal...................... 80/300 95/360 110/420
>Yellow turn signal rear.............. 130/750 150/900 175/1050
>Yellow turn signal front............. 200/- 240- 275/-
>Yellow turn signal front \3\......... 500/- 600/- 685/-
>------------------------------------------------------------------------
>\1\ Maximum at H or above.
>\2\ The maximum candlepower value of 125 applies to all test points at H
> or above. The maximum allowable candlepower value below H is 250.
>\3\ Values apply when the optical axis (filament center) of the front
> turn signal is at a spacing less than 4 in. (10 cm.) from the lighted
> edge of the headlamp unit providing the lower beam, or from the
> lighted edge of any additional lamp installed as original equipment
> and which supplements the lower beam.
>
>
> Figure 1c--Sum of the Percentages of Grouped Minimum Candlepower
>------------------------------------------------------------------------
> Turn
> Group and test points signal Stop Parking Tail
>------------------------------------------------------------------------
>1 10U-5L, 5U-20L, 5D-20L, 65 65 60 70
> 10D-5L.....................
>2 5U-10L, H-10L, 5D-10L..... 125 125 75 120
>3 H-5L, 5U-V, H-V, 5D-V, H- 475 475 420 480
> 5R.........................
>4 5U-10R, H-10R, 5D-10R..... 125 125 75 120
>5 10U-5R, 5U-20R, 5D-20R, 65 65 60 70
> 10D-5R.....................
>------------------------------------------------------------------------
>
>
>
--
David Beierl - Providence RI USA -- http://pws.prserv.net/synergy/Vanagon/
'89 Po' White Star "Scamp"
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