Functions and parameters of auto-darkening helmets

Functions and parameters of auto-darkening helmets

• Protection against UV and IR radiation Each helmet has a UV (ultraviolet radiation) and IR (infrared radiation) filter that reflects and absorbs harmful radiation. It allows only safe rays of visible light to enter the welder's eyes. The UV and IR filter provides permanent protection regardless of whether the welding filter is in the dark or light state.
• The shade level determines the degree of shade of the filter. Most often it is expressed in the DIN unit (German industrial standard). The shade level is selected depending on the welding process and the welding current. The helmets differ in the range of shade level adjustment. Those of the higher class have a smooth adjustment of the shade level in the range of at least 9-13 DIN.
• Switchover time (light to dark) - The time that elapses from the moment the welding arc strikes until the ADF filter goes dark. The time should be as short as possible to protect the welder's eyesight and prevent glare. The time is given in the parameters of the helmet. It is well below the millisecond.
• The sensitivity function allows you to set the sensitivity of the sensors depending on the welding process and conditions at the workplace. If bright light from nearby welding stations causes the ADF to darken prematurely, you can reduce the sensitivity. This will eliminate the interference. When the filter does not darken when attempting to weld at a low amperage, sensitivity can be increased until the ADF is operating correctly at the required distance.
• Delay function (dark to light) - the material to be welded may glow even after the end of welding, depending on the welding process, material and temperature. If the welding helmet quickly switches from dark to light after welding, the welder may experience a brief blinding. In such cases, the delay time should be set to a greater value. During spot welding, the delay time can be set low so that the ADF quickly reverts to the bright setting, allowing the welder to progress smoothly to the next weld point.
• Detection angle adjustment - Reducing the detection angle reduces the risk of inadvertent darkening of the ADF due to sudden bright light during operation or light from another welding station in the immediate vicinity.
• Grind Mode - If the helmet has this feature, it means the ADF can be set to "light" for the duration of the sanding process. It prevents the filter from darkening due to pulsating light during grinding.
• Field of view dimensions - the helmets are equipped with ADF filters of various dimensions, which affects the price of the product. Higher class helmets provide a field of view of min. 50x100mm.

Selection of auto-darkening helmets

The basic parameter of an auto-darkening helmet is the level of darkness that can be set on the helmet. The table contains indicative darkness values for various welding methods and currents. Simpler helmets have a narrow range of protection class, e.g. 10 and 11DIN. It is sufficient for welding in the medium current range. However, if we are going to weld in a wide range of currents, the helmet should also have a wider range of regulation - it would be best if it had a smooth regulation.

Table: Recommended degrees of protection in accordance with EN169: 2002. Individual perception may require the protection level setting to be adjusted within +/- 1.

When the scope of protection (darkening) is determined, the helmet should be selected in terms of other parameters. The price range of active helmets is large. Simpler and cheaper models will only be good if the welding is casual. However, if the protection is to be used by a professional welder for continuous work, the helmet should be of high quality, with excellent parameters, ensuring a wide range of adjustment of all parameters.