Interpretation ID: 3135o
Chief Engineer
Wesbar Corporation
P.O. Box 577
West Bend, WI 53095
Dear Mr. Cunningham:
This is in reply to your letter of September l4, l988, attaching two lamps, and asking for an interpretation of Motor Vehicle Safety Standard No. l08 with respect to each. Specifically, you wish clarifications of SAE J588e, "the definition...2.2 'Multiple Compartment Lamp' and the term used in 3.1 'Single Compartment Lamp'".
SAE Standard J588e Turn Signal Lamps, incorporated by reference in Standard No. l08, defines a multiple compartment lamp as "a device which gives its indication by two or more separately lighted areas which are joined by one or more common parts such as a housing or lens." The term "single compartment lamp" is not used in section 3.1, though the term "single compartment photometric requirements" is used in referencing the values for one "lighted section" given in Table 1 of J588e. For purposes of this discussion we shall define a "single compartment lamp" as one that gives its indication by one lighted area.
You have described your first lamp as "a housing with back and four sides containing a two filament bulb with a single lens covering face of housing." The lamp photometrically complies to the basic requirements of a Class A tail, stop and turn signal lamp. You have asked if this lamp is a single compartment lamp. The answer is yes; your model 3504 Exp. contains a single light source and has a single lighted area.
Your second lamp is described as "a housing with a back, two sides and one end, containing one #57 bulb and one #ll57 (2 filament) bulb. This housing is closed with two red lenses, one on the end and one on the face with an additional clear lens on bottom side. This lamp also complies to all standards of a class A tail, stop and turn lamp plus side marker clearance, license plate illuminator and class a reflex reflector side and rear". You ask if this also is a single compartment lamp. The answer is yes. The term "separately lighted area" in the definition of a multiple compartment lamp is understood to mean an area that is illuminated by a separate light source. In your model 3504 the turn signal light is provided by the #ll57 bulb alone, and not in tandem with the #57 bulb.
I hope that this provides the clarification you seek. We are returning your lamps under separate cover.
Sincerely,
Erika Z. Jones Chief Counsel
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