D2S / D2R HID Xenon vs. H7 Bulb
Comparing 2 standards across 11 specifications. 11 key differences identified.
D2S and D2R Bulbs (standardized under UN ECE Regulation 99 with a P32d base) are High-Intensity Discharge (HID) automotive lamps that produce light by igniting an electric plasma arc inside a quartz glass chamber filled with Xenon gas and metal-halide salts. Operating at 35W nominal and generating an intense 3,200 lumens (~2.1× the brightness of halogen).
The H7 Bulb (standardized under UN ECE Regulation 37 with a PX26d flanged base) is the most widely used single-filament halogen automotive headlight bulb in the world. Operating at 55W nominal at 12V (rated at 13.2V test voltage), it generates 1,500 lumens (±10%) primarily for low-beam projector and reflector headlight assemblies.
Specification Comparison Table
11 Parameters| Parameter / Spec | ||
|---|---|---|
|
Standardization
|
UN ECE R99 Category D2S / D2R / US DOT Category D2S | UN ECE R37 Category H7 / IEC 60061-1 sheet 7004-5 / US DOT Category H7 |
|
Base Socket Designation
|
P32d-2 (D2S for projector lenses) | P32d-3 (D2R with black ceramic mask for reflector optics) | PX26d (pre-focused metal circular mounting flange with one flat reference indexing tab) |
|
Luminous Flux Output
|
3,200 lumens ± 15% (Color Temperature: 4150 K to 4300 K standard OEM daylight) | 1,500 lumens ± 10% (at 13.2 V) |
|
Arc Chamber Chemistry
|
Xenon gas (provides instant initial glow) + Mercury + Metal-Halide salts (ScI₃ / NaI create daylight white plasma arc) | — |
|
Operating Power & Voltage
|
35 W continuous @ 85 V AC steady-state electronic ballast voltage (draws ~0.41 A) | — |
|
Ignition Arc Voltage
|
23,000 V to 25,000 V (23–25 kV pulse from external electronic ballast igniter creates initial spark arc) | — |
|
Average Lifespan
|
2,500 to 3,000+ hours (5x to 8x longer than halogen tungsten filaments) | — |
|
Filament Type
|
— | Single axial tungsten filament (no internal shield; strictly a single-beam bulb) |
|
Nominal Power & Voltage
|
— | 55 W @ 12V nominal (tested at 13.2V standard regulation voltage; draws ~4.17 A) |
|
Average Lifespan (B3 / Tc)
|
— | B3 (97% survival): ~330 hours | Tc (63.2% failure): ~550 hours (standard halogen) |
|
Electrical Terminals
|
— | 2 spade push-on terminals (6.3 mm faston tabs spaced 14.5 mm apart) |