ML25LT LED 2-Cell C Flashlight

See links below to alkaline battery care at Energizer and Rayovac.

A MAGLITE® flashlight’s LED light engine is a permanent component, not a “perishable” or “consumable” item like a battery or an incandescent lamp. In normal use, the LED should last for the life of the owner and should never need to be replaced.

The explanation for these statements is a little complicated. It starts with answering a preliminary question, which is, “How do you define when the useful life of an LED is at an end?” With an incandescent (filament) lamp, this question is so easy that nobody even asks it: The life of an incandescent lamp is over when it burns out. The “burning out” of an incandescent lamp is a sudden, catastrophic, complete failure; there’s no mistaking it when it happens. “Burnout” occurs when the lamp’s filament (typically made of tungsten, a very high-melting but brittle metal), grows so thin and weak that it can’t support its own weight, especially if it is jarred. So the filament breaks. When it does, the flashlight can’t complete the electrical circuit that ordinarily would flow through the filament, so if you turn on the flashlight, it does not give any light. When we say that an incandescent lamp is “dead,” what we actually mean is that its filament has suddenly and catastrophically failed.

But if we ask the same question about an LED – “How do you define when the useful life of an LED is at an end?” – the answer is not nearly that simple because an LED typically does not fail suddenly and catastrophically: There’s no filament to “burn out,” nor is there any other clear, distinct event you can point to and say that the LED is dead. Instead, what typically happens to an LED is that its light output extremely slowly, and extremely gradually, declines with use.

Much of the literature states that in a typical installation, an LED should perform for 50,000 to 100,000 hours before its light output falls to 50% of its initial output. So if we define 50% as the end-of-useful-life point, and if a flashlight is used for 1 hour a week (and even that might be a lot for a typical homeowner, who would use the flashlight sporadically, occasionally and in short episodes), the LED’s “useful life” (as defined above) should be 50,000 to 100,000 weeks – that is, between one and two thousand years. Even if the user is a night watchman whose flashlight is actually on for 4 hours a night, 5 nights a week – which would be a lot — the LED’s “useful life” (as defined above) should be between 1,666 and 3,333 weeks (i.e., between 48 and 96 years).

Also to keep in mind is that the “50%-of-initial-light-output” definition of the “endpoint of an LED’s useful life” is an arbitrary definition, and one can argue that it is much too short: 50% of the initial light output of a high-powered LED flashlight is still a lot of light, and it seems doubtful that a typical user would discard the flashlight at that point (even if he lived long enough to reach that point). For comparison, the widely-followed ANSI/NEMA FL-1 Flashlight Basic Performance Standard (2009), in prescribing how to rate a flashlight’s “Run Time” on a fresh set of batteries, defines the endpoint of the “useful life” of batteries to be the point where light output declines to 10% — not 50% — of initial output. So in the view of the committee that drafted the ANSI Standard, 10%, not 50%, of initial light output is the reasonable point at which to say that the user would likely regard the batteries as no longer fit for use and in need of replacement. If we were to define the end-point for an LED’s “useful life” as 10% rather than 50% of initial light output, then we might need to speak in terms of a “useful life” of centuries rather than years.

Nobody would claim, however, that an LED is completely bulletproof under all conditions. It should go without saying that one who uses his LED flashlight as an impact tool or a fire-poker is looking for trouble. And, for example, if an LED were driven grossly in excess of its design-rated voltage and/or current, it could fail quickly. Even if an LED were driven somewhat (but not grossly) in excess of its rated voltage and/or current over a long period of time, that could accelerate the rate at which its light output would decline. Excessive operating temperatures could also threaten the longevity of an LED. MAGLITE® flashlights, however, are carefully engineered to keep voltage and current within rated specifications when used with batteries of the correct voltage; and means including good, efficient heat-sinking are built in to keep operating temperature within rated bounds.

In view of all this, the statement with which we started this discussion is quite reasonable: A MAGLITE® flashlight’s LED light engine should be seen as a permanent component, not a “perishable” or “consumable” item like a battery or an incandescent lamp; and the user should expect the LED, in normal use, to remain serviceable for his or her entire lifetime, never needing to be replaced.

When you cannot remove the tailcap to change the batteries, it is probably that the batteries leaked and caused corrosion inside. Mag Instrument does not warrant against battery leakage. If the flashlight has been damaged by leakage of batteries, do not return the flashlight to Mag Instrument but determine what brand of battery caused the damage and follow the battery manufacturer’s instructions about how to make a damage claim. For details, see the above FAQ entitled “If my flashlight is damaged by a battery leak, what should I do?”

When this happens, it probably means that the batteries have leaked and are stuck inside the barrel. Oftentimes, batteries will swell before leaking, causing them to get stuck inside the barrel. Mag Instrument does not warrant against battery leakage. If the flashlight has been damaged by leakage of batteries, do not return the flashlight to Mag Instrument but determine what brand of battery caused the damage and follow the battery manufacturer’s instructions about how to make a damage claim. For details, see the above FAQ entitled “If my flashlight is damaged by a battery leak, what should I do?”

Yes, unfortunately, they can.

All alkaline batteries are filled with a caustic material that can damage (corrode) any device, including a flashlight, if it escapes from the battery cell. Given the limitations of alkaline battery technology, there is always some risk that a battery might leak under some conditions. There are a number of specific reasons why this might happen. One is a defect in the battery, or physical damage to it. Another reason has to do with the fact that all alkaline batteries have a self-discharge rate, causing them to gradually weaken and die even if they are in a package on a shelf, or in a device that is not used. Leaving dead batteries inside a device can cause battery leakage and resulting corrosion damage. Putting new batteries together with old batteries, and/or with batteries of a different type, can also cause rapid discharge, pressure buildup, and leakage. And misuse of the batteries (e.g., by attempting to recharge batteries not designed to be recharged) can also cause leakage that can damage or destroy the flashlight.

Visual signs of battery leakage and crusty deposits (corrosion) inside your flashlight are a sign of leakage and damage, and if the flashlight is non-functional, this corrosion damage is likely the cause.

It sometimes happens that batteries become stuck inside the barrel and are hard to remove. If this happens, it likely means that the batteries have leaked and have swelled up, and if the flashlight is non-functional, corrosion damage from the leaking batteries is almost certainly the cause.

It also sometimes happens that the tailcap becomes stuck on the flashlight and is difficult to unscrew. When this happens (and there is no evidence of barrel crushing or denting), the cause likely is that a battery leaked and produced corrosion that involved the tailcap threads, seizing of the tailcap onto the flashlight’s barrel.

In any of these situations, the likely cause is alkaline battery leak damage.

Because our warranty excludes battery-leak damage, you should NOT take or send the flashlight to Mag Instrument’s Warranty Service Department.

What you CAN do is contact the battery manufacturer to see if it has a program to repair or replace your leak-damaged flashlight.

Every reputable alkaline battery manufacturer has some form of device damage policy under which you may be eligible to have your flashlight repaired or replaced if it has been damaged by leakage of alkaline batteries that came from that manufacturer.

(NOTE: It is good practice to write down and remember the brand name of any batteries you put in the flashlight. If leak damage does occur, it is sometimes difficult or impossible to get the batteries out of the barrel to see what brand they are.)

Different battery makers may call their device damage policies by different names, and the exact terms may differ from one maker to another and may change over time. Some of the policies may have special requirements, so it may be important to contact the battery manufacturer without delay if you discover battery leak damage. And do not discard the flashlight or the batteries before finding out whether the battery manufacturer requires you to submit them as proof of claim.

You should communicate with the battery manufacturer before you send them the damaged flashlight, and should confirm exactly what their device damage claim eligibility requirements and procedures are.

Information can typically be found on the battery manufacturer’s website, and/or on its retail packaging for batteries, and/or via a customer-service phone number appearing on its website or retail package.

For your convenience we provide the following website links and contact numbers through which you can get more information concerning battery-leak-damage policies and procedures of various battery manufacturers.

Duracell® –

www.duracell.com/en-us/technology/battery-care-use-and-disposal

Support Team 1-800-551-2355

Energizer® –

www.energizer.com/about-batteries/battery-leakage

Customer Service 1-800-383-7323

Ray-O-Vac® –

www.rayovac.com/contact/warranty-and-guarantee.aspx

Customer Service 1-800-891-6091 or 1-800-237-7000

Please understand that the battery manufacturers are companies separate and independent of Mag Instrument. Mag Instrument did not create, does not control, and cannot be responsible for the terms or operation of battery manufacturers’ device damage policies and practices. The above battery manufacturer contact information, current as of late September 2016, is provided to you as a courtesy but is, of course, subject to change by the battery manufacturer.

Each of our incandescent lamps was designed and developed with only one purpose in mind – to operate optimally in the particular flashlight for which the particular lamp is designated. We publish data describing how each lamp performs in its flashlight – for example, our website, catalog and package literature supply light output, peak beam intensity, beam distance and run time numbers for the 3-D-cell Maglite® flashlight running the lamp you mention. All such data are based on testing according to the ANSI/NEMA FL-1 Flashlight Basic Performance Standard (2009). We do not, however, test for or publish current-draw or wattage figures for the lamp itself, as these are not ANSI performance categories.

Just as we do not publish any claim, we also do not guarantee any rating, as to the current draw or the wattage of the lamp you reference.

You may get at least an approximate idea of how much current your particular specimen of the lamp draws when operating in its intended application, and an idea of the wattage and voltage drop, by putting it in the flashlight for which it was designed (a 3-Cell Maglite® flashlight, in the case of the LMXA301 Xenon lamp) with fresh batteries, illuminating the lamp, and using an ammeter to measure the current flow across the lamp terminals, and a voltmeter to measure the voltage, and then doing a wattage calculation according to the formula

Voltage (in volts) times Current (in amperes) equals Power (in watts)

Thus, if the voltage drop is 4.2 volts and the current flow is 720 milliamperes , the power output is 4.2 volts X 0.72 amps = 3.024 watts. You would, however, need to look to the accuracy of your own equipment and the correctness of your own technique. Mag Instrument is not in a position to warrant the accuracy or the typicality of whatever current-draw, voltage-drop or wattage numbers you might obtain.

Bi-Pin Retrofit1 PDF