In heavy-duty work environments, LED and HID work lamps offer decisive advantages over conventional bulb technology.

LEDs and HID compared to incandescent bulbs, require significantly less power consumption resulting in minimal strain on both alternator and battery, making LED work lamps the ideal lighting solution for work machines and equipment with low alternator performance or with battery-assisted power supply.

LED technology features:
•  High energy efficiency
•  Longevity
•  Multivolt™ capability
•  Vibration resistance
•  Dust and moisture sealing

Paraboloid work lamp
A conventional work lamp has a reflector in the mathematically defined shape of a paraboloid. The reflector captures the light of the bulb and directs this forward to the area to be illuminated.

The specific light distribution pattern is produced by optical lenses and prisms in the profiled cover lens which achieve limited scattering of the beam of light. Effective paraboloid headlamps need a large reflector in order to be able to capture a large amount of light from the bulb.

Modern Free-Form (FF) Work Lamps
In contrast to the paraboloid work lamps, the Free-Form (FF) reflector does not incorporate a cover lens that distributes and scatters light. The computer-calculated Free-Form (FF) reflector produces the required beam pattern.

Free-Form (FF) Work Lamp with H9 Bulbs
Easy replacement of the H9 bulb without having to open the lamp. Hella is the first supplier worldwide to use H9 bulbs in work lamps. The use of H9 bulbs has important advantages for the operator:

•  H9 bulbs offer better light output than H3 bulbs. H9 bulbs supply some 45% more luminous flux.
•  The bulb is accessible from the outside, which means fast and easy replacement without tools.

Never touch the glass bulb itself. Fingerprints on the glass bulb burn in an opaqueness which leaves a deposit on the bulb or the reflector. Under such conditions early failure of the bulb cannot be ruled out.

Unlike conventional bulbs, Xenon bulbs do not have a bulb filament. Rather, the light is produced using an electric arc. A mixture of the inert gas, Xenon, and metallic salts is enclosed in a glass bulb the size of a matchstick head. The light arc is ignited between two electrodes. A sophisticated electronic ballast is necessary for this process.

The high voltage of 20,000 volts necessary for the ignition of the light arc, is produced by a 3rd Generation ballast or in the base of the D1S Xenon bulb. The advantages of work lamps using HID Xenon bulbs in comparison with a 55 watt halogen bulb include the following:

•  2.5 times the luminous flux and at the same time 23% less power consumption.
•  Increased luminance results in a brighter and larger illumination of the working area.
•  Light spectrum is similar to daylight – for natural colour reproduction of the environment.
•  Vibration-proof light arc instead of a sensitive breakable filament.
•  Service life up to five times longer – reduced expenditure for bulb replacement.
•  Constant brightness – independent of fluctuations in the current supply thanks to the electronic power control in the ballast.

Hella is one of the leading designers and manufacturers of electronic ballasts for HID lamps. Many millions of the first three generations of ballasts are installed in vehicles around the globe. The 4th Generation Ballast is another milestone for our engineering team.

The 4th Generation Ballast offers some advanced features and decisive advantages:

•  No high Voltage cable between Ballast and HID bulb.
In contrast to work lamps with 3rd Generation Ballast, the high starting voltage is generated in the protected bulb socket of the D1 HID bulb. The complex and costly high voltage plug to connect the HID bulb has been eliminated. A highly flexible connection cable with a much smaller diameter connector offers a flexibility of luminaire design and lamp installation.

•  Cable length between ballast and lamp of up to 3m.
The much longer cable between ballast and lamp offers the installer a much greater degree of flexibility.

•  Electronic ballast can be separated from the lamp.
A plug-in connection on the 4th Generation ballast makes it possible to remove the connection cable to the headlamp.
This means the connection cable can be fed through an opening in the bodywork and the ballast mounted inside the vehicle.
This makes mounting even easier.

1.  Beam distribution is very important. Make sure you choose a beam pattern which suits your application.

2.  Always use quality cable, relays and switches. Hella has a complete range available - ask your supplier for more information.

3.  For more flexible illumination with greater manoeuvrability, consider using a pedestal mounting bracket.

•  Work lamps are supplied with wiring harness, relay and fuse for connection to vehicle. The start-up current of 20A (for 12V) or 10A (for 24V) requires a relay under all circumstances. A 15A fuse is required (for 12 and 24V systems).

•  When extending the power supply wiring harness, sufficient cross section must be ensured. The internal resistance of the electrical connection (including relay, fuse and earth lead) between ballast and battery, must not exceed 150 milliohms (for 12V) or 300 milliohms (for 24V) under all circumstances. If the resistance is higher, the current of 20A (for 12V) or 10A (for 24V) required for ignition of the light arc cannot be reached. Insufficient voltage will cause damage to the electronic system.

•  Ignition problems can occur with Xenon lamps when a number of ballast units are started simultaneously. This can result in damage to the electronic components. For this reason, the start up of several Xenon lamps should be staggered. The duration of this interval depends on the vehicle’s electrical equipment.

Due to the design of the HID bulb, the angle of the inclination measured from the horizontal position, must not exceed +/– 35 degrees. A greater angle of inclination will reduce the lifetime of the bulb.

The IP degrees of protection are defined by DIN 40 050 part 9. The purpose of the standard is to define the protection of electrical equipment in vehicles against penetration by foreign particles including dust, and against ingress of water.

The exact definition of the degree of protection is achieved by means of different tests. Hella work lamps fulfil at least IP 5K4K (protection against dust and water splashing).


Please refer to the Technology section for further information.