This report summarizes the features and general parameters of Petzl headlamps to help consumers make a decision.
Measurement protocol
Petzl offers a wide variety of products and it has developed a measurement protocol to analyze performance of its headlamps. Summarizing:
• Five headlamps of a same model are selected randomly from the production line and they are tested.
• All of them are checked with a pair of new and standard batteries sets. Headlamps sold without batteries, are checked with a pair of new alkaline batteries.
• To approve results, every measurement is performed at 20 º C of temperature.
• Every parameter is tested ten times. The final value is the average of all measurements.
Features headlamps analyzed
Minimum illumination
It is the amount of light need to be able to see properly. This feature is really important to set autonomy. Petzl estimates that there is the minimum level of illumination (0.25 lux) * in a night with full moon.
* Lux is defined as the measurement unit of illuminance or lighting level. Equivalent to lumen/m2.
Battery range
It is the time during which the headlamp illuminates with the minimum level of lighting or higher level, which is measured two meters away, on the axis of the beam of light. If the illuminance value is lower than 0.25 lux two meters away, it is considered that the flashlight is no functional.
Lighting range
Is the distance from which the headlamp illuminates with a higher level of lighting than 0.25 lux.
Luminous Flux
Also called luminous-power, it is the amount of light that a flashlight emits. This value is expressed in lumens (lm). Luminous flux and Lighting range is measured in laboratory at the same time.
Petzl indicates that the maximum power lighting it´s the luminous flux in higher level, ie, with batteries are full charged.
Reference values:
• A candle à 10 lumens.
• House lighting à 100-200 lumens.
Petzl headlamps light between 50-350 lumens.
Adjustments to the lighting of the Petzl headlamps
Shape of beam
Every beam of light has a residual part more wide-ranging than the main beam, it increases visibility.
The beam can be homogeneous or inhomogeneous. Petzl headlamps are always homogeneous.
Homogeneous
Inhomogeneous
The shape of beam depends on the type of light source and optics. There are two types of beams.
- Wide-range.
The beam spreads close around it. It is better suited to static or quiet activities.
- Focused.
The headlamp illuminates longer distances. It is better suited to fast walks.
Lighting power
Petzl headlamps are able to illuminate with variable power, to solve all type of situations. The different modes of lighting are: maximum, optimum, economic, intermittent and Boost. The user can use headlamps according to he wants and he needs.
Boost mode is able to increase the light output by 50% over the maximum level. On the other hand, the intermittent mode is used in emergency situations and to be located.
Protective coating and electromagnetic compatibility
Headlamps are guaranteed on many uses and weather conditions; therefore every headlight has a protective coating (IP XX) and an indication of the level of compatibility.
XX IP: (protective coating), the first number indicates the level of protection against solids, while the second number indicates the level of protection against liquids.
Petzl headlamps are classified as: IPx4, IPx6 and IPx8.
• The types, IPx4, IPx6, called water resistant, can stand the worst weather conditions (high humidity, rain, snow, quick dip, etc.). They are able to work even if there is water inside. It is possible thanks to its more fragile parts are made of a sealing layer and stainless steel.
• The type IPx8 is waterproof. It resists more than 30 minutes underwater at 1-5 meters of depth.
The following table explains the nomenclature:
| Protection against solids objects | |
| X = No testing. | - |
| 0 = No protection. | - |
| 1 = Protection against solid objects ≥ 50 mm diameter |
|
| 2 = Protection against solid objects ≥ 12.5 mm diameter. |  |
| 3 = Protection against solid objects ≥ 2.5 mm diameter. |  |
| 4 = Protection against solid objects ≥ 1 mm diameter. |  |
| 5 = Protection against dust (limited, no harmful amount.) |  |
| 6 = Sealing to dust. |  |
| Protection against liquids | |
| X = No testing. | - |
| 0 = No protection. | - |
| 1 = Protection against vertical drops. |  |
| 2 = Protection against drops (15° inclination). |  |
| 3 = Protection against rain water (60° inclination). |  |
| 4 = Protection against water discharges. It works although water gets inside. |  |
| 5 = Protection against water jets. |  |
| 6 = Protection against strong water jets. It works although water gets inside. |  |
| 7 = Temporal immersion (down to 1 meter underwater for 30 minutes). |  |
| 8 = Indefinite immersion (below 1 meter underwater for a time is defined by the manufacturer). |  |
Electromagnetic compatibility EMC
It is the ability of an electrical device to work properly when it receives electromagnetic interference and it doesn´t cause them itself.
Petzl headlamps are tested according to the directive 89/336/EEC on electromagnetic compatibility: they cannot generate any interference to other EC marked devices.
Features LED lighting
The LEDs are individually shaped capsule, they have no filament. They use lower power and they are longer lifespan. They are a wide variety of shapes and colors.
Types of LEDs:
• Cylindrical LED 5mm in diameter with an integrated lens. They don´t require a wide angle lens to get close lighting. They are tough to impacts and vibrations.
• High performance LEDs. They require an additional lens to scatter light which also provides protection against impacts.
The lifespan of LED is determined when its output is reduced by 50% over the original. Quality LEDs are a lifespan on 100,000 hours normally. The light is very weak later. A general Led is a lifespan on 5,000 hours if it works continually.
Lenses and Reflectors
Petzl headlamps incorporate reflectors (light bulbs) or lens (LEDs).
The lenses are a very important element of the illumination. The user can adjust the light which Led emits. The lens can be fixed or adjustable; so the user is able to adjust the spotlight according to the situation. The lenses are made of glass or plastic and are relatively compact. According to the forms, they can emit a diffuse or focused light.
The reflectors surrounding the light bulbs act like mirrors. They direct the light in a certain direction. Their shapes are parabolic or flat and they both have a reflective inner surface.
The reflectors are used in the headlamps with light bulbs. The design of the reflectors try to increase lighting efficiency; generate a uniform beam of light and reduce the possible imperfections on it due to the shape of the filament, the crystal quality or the presence of several lamps. The reflectors are usually made with protective lenses. The Petzl headlamps make of reflectors can adjust the beam of light.
The high performances LEDs light at 180o. The lens causes the beam is focused and guided. Petzl lenses are designed to produce the most efficient lighting and the most uniform light beam.
The headlamps with lenses emit a narrow light beam over long distances. To get a wide and close lighting, Petzl designed a retractable wide-angle lens made of several micro-lenses.
On the other hand, 5 mm LEDs have a support that fixes and guides the light beam. Petzl only introduces a silver-tone finish which gets better visibility.
Batteries
Every battery is polarized; it has a positive and negative pole. We have to put it correctly because it can become unstable and emits gases and corrosive liquids.
Rechargeable batteries
They can be recharged between 200 and 1500 times. Some Petzl headlamps have an indicator light of charge, as shown below:
Flashing green: successfully charged battery.
Flashing orange: charge lower than 30%.
Flashing red: charge lower than 10%.
The discharge process of the batteries depends on the elements are used and conditions for use, quality of parts and assembly. Petzl headlamps may incorporate an electronic device that adjusts the working of headlight. Therefore, there are two types of headlamps: regulated and unregulated.
Working of regulated headlapm
The scope of unregulated headlamps decreases at the same time the discharge of battery, whereas regulated headlights keep the scope constant for a period of time (this time appears reflected on the performance as autonomy). Light output decreases to a minimum later so that the user can change the batteries.
Working of unregulated headlapm
For unregulated headlamps, Petzl checks them at 30 minutes, 10 hours and 30 hours to continuing use.
On the other hand, Petzl define as effective signage lighting that it is visible from 100 meters. The specified autonomy on the headlights is the time during the headlamp emits a signal higher or similar than 0.00001 lux from 100 meters away on the same axis.
Electrical power is supplied by rechargeable batteries and it comes from the processing of chemical energy into electrical energy when the battery is connected to the electrical circuit. The chemical process that occurs in rechargeable batteries is reversible, therefore they can be recharged.
Rechargeable batteries also have polarity so they will have a specific placement inside headlamp. If they are incorrectly inserted, the batteries might suffer an overload. If you insert a charged battery and it provides a poor light beam, you should check immediately the placement of the battery.
The most important load parameters are the voltage, current and time.
The time of charge depends on battery type and its use. Petzl always advise to charge the battery correctly and do not exceed the time, as it has a maximum capacity. If you continue charge the battery, it could be overcharged. Apart from that the charge process generates excessive heat and it can lead to premature wear (memory effect, which refers to the rechargeable Ni-Cd and to a lesser extent Ni-MH, suffer from premature aging when the processes of charge/discharge are not finished).
Capacity
The battery capacity is measured in amp/hours (Ah). The higher capacity it has the longer headlamp illuminates. The capacity depends on the battery type (alkaline, lithium, etc.), the number of components, its structure and temperature. Each manufacturer uses a different measurement system.
Saline batteries
These batteries are cheaper and have a lower performance. They work for low power electrical appliances such as clocks, radio receivers and remote controls. Nowadays, they are disappearing. Petzl advises against we use them because they have a poor performance and make possible damage.
Alkaline Batteries
Nowadays, they are the most common batteries in the market. They are well suited to most electrical appliances and they can be stored longer time.
Lithium Batteries
They are smaller volume, lighter weight, higher output at several temperatures and higher capacity (30% longer than alkaline batteries with the same size).
When the headlamp works, the battery runs down in different ways. It depends on the technology and quality materials. The alkaline battery voltage decreases steadily during it works, while lithium batteries voltage decreases in stages.
Lithium batteries provide several outputs depending on the type. The 1.5V batteries provide constant illumination for most of its lifespan, whereas the output of the 3V batteries decreases steadily.
These batteries use a lithium ion or polymer (Li-po). They are more expensive and lighter than others. These batteries are used in products of high electrical requirements such as mobile phones or laptops. They require an adapter to be charged and they have an electronic protection circuit that controls the voltage when they are loading, their temperature, etc.
Rechargeable lead batteries
It is an old and cheap model battery. They are very tough and provide a lot of energy but they are quite large.
Nickel batteries
These batteries are actually made up of nickel-cadmium (Ni-Cd) or metal hydride (Ni-MH). Ni-NH is currently the most widely used. This type supplies a high energy density but it runs down faster and it doesn´t put up with many charges/discharges.
The Ni-Cd technology remains popular because it offers a current higher than Ni-MH, Li-Ion or others rechargeable batteries.
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