K4375-3 - Lincoln Viking 1740 Ignition Series Auto-Darkening Helmet

Technical Overview: Lincoln Viking 1740 Ignition

The Lincoln Electric Viking 1740 Ignition Welding Helmet (K4375-3) is an auto-darkening hood engineered for general fabrication and structural welding applications. This model integrates Lincoln's proprietary 4C Lens Technology, which utilizes a specialized liquid crystal display (LCD) to filter light more naturally. Unlike traditional auto-darkening filters that impart a lime-green tint, the 4C technology provides a true-color view of the arc, puddle, and base material, reducing eye strain and improving weld accuracy. The lens achieves a perfect 1/1/1/1 Optical Clarity rating according to EN379 standards, ensuring zero blurriness, distortion, shade inconsistency, or angle non-uniformity.

The ADF (Auto-Darkening Filter) features a viewing area of 6.3 square inches (3.78 x 1.67 inches), providing ample visibility for various welding positions. It offers a variable shade range of DIN 9 to 13, adjustable via internal analog controls. Sensitivity and delay settings allow the operator to customize the lens response based on ambient lighting and amperage levels. The helmet is TIG rated for low-amperage applications (≥ 5 Amps AC/DC) and features a switching speed of 1/25,000 of a second. Power is supplied by a solar cell assisted by two user-replaceable AAA alkaline batteries, eliminating the need for non-standard lithium coin cells.

Structurally, the shell is designed for durability and minimal weight, tipping the scales at just 18.6 oz (528 g). It includes a dedicated Grind Mode, activated externally, with an internal green LED indicator to alert the user when the helmet is not in welding mode. The suspension system utilizes a ratchet-style headgear with a soft front headband and a large backpad to distribute weight evenly. This unit is compatible with cheater lenses and hard hat adapters (sold separately).