Product Specifications

I. Overview & Professional Positioning

The 24V H3 (PK22S) is a high-performance single-filament halogen bulb designed specifically for the 24-volt systems of commercial vehicles (trucks, buses, construction machinery). Its unique PK22S prefocused bayonet base and lead-wire construction make it an ideal light source for fog lights, auxiliary driving lamps, and work lights in harsh environments. Reinforced to withstand mud, vibration, and extreme temperatures, this model is a critical functional component for ensuring safety in low-visibility conditions on commercial vehicles.

II. Core Engineering Advantages

1. Full-Environment Sealed Design:

   • Lead-Wire Seal Construction: The bulb incorporates an integrated rubber or silicone seal gland at the lead exit, preventing moisture ingress into the socket even under high-pressure spray or muddy conditions, thereby eliminating short circuits and corrosion.

   • Vibration-Resistant Mechanical Lock: The PK22S base is secured via a spring clip or screw mechanism, offering superior resistance to loosening compared to plug-type bulbs.

2. Adverse-Weather Penetration:

   • Typically emits 3000K-3500K warm yellow light, which scatters less in rain, fog, snow, and dust, offering significantly better penetration than white light.

   • The prefocused filament position, combined with a dedicated reflector, produces a wide, flat beam with a sharp cutoff, effectively illuminating the road surface ahead without creating blinding glare.

3. Commercial-Grade Durability:

   • Standard 24V/70W rating is designed for high-current commercial vehicle circuits with heavier-gauge wiring and connectors.

   • Features a thickened quartz envelope made from impact-resistant glass formulation for better stone chip resistance.

III. Key Identification & Compatibility

• Core Identifier: PK22S base. This is a metal prefocused base with fixing holes/slots, typically requiring a clamp plate or retaining screw. The bulb has two high-temperature insulated lead wires.

• Voltage & Wattage: Clearly marked "24V 70W". Never use in a 12V system.

• Applications:

  • Primary Use: Front fog lamps on commercial vehicles.

  • Secondary Use: Auxiliary driving lamps (providing wide flood light off-road), work lighting on construction machinery.

  • Common Vehicles: Original or compliant aftermarket fog lights on European trucks (Scania, MAN, Iveco), domestic heavy trucks (FAW, Dongfeng), and medium/large coaches.

• Compatibility Warnings:

  • Absolutely forbidden to mix with 12V H3 bulbs (lead connectors may be similar, but voltage mismatch causes instant burnout or insufficient output).

  • Must use the original seal gland and retaining hardware to ensure waterproof integrity.

IV. Professional Installation & Maintenance Guide

1. Safe Power Disconnection: Always disconnect the vehicle's main power switch before replacement to prevent short circuits.

2. Seal Integrity is Paramount:

   • When removing, preserve the original seal gland and clamp.

   • During installation, ensure the lead seal gland is fully seated in the lamp housing groove without twisting or damage.

   • Tighten retaining screws to the specified torque for even pressure without damaging the bulb.

3. Lead Connection: Use the original connector or a waterproof splice to connect the leads securely, with proper insulation.

4. Regular Inspection: During routine vehicle maintenance, check for cracks in the fog lamp lens, aging seals, and heat-embrittled leads.

Summary

The 24V H3 (PK22S) is a professional-grade core component for functional lighting on commercial vehicles. Its value lies in providing all-weather, high-reliability, high-penetration fog and auxiliary lighting solutions for trucks and buses, specifically engineered for bad weather and complex road conditions. Correct selection, installation, and sealing are critical to its performance and lifespan in extreme environments.