Maglite Overheating Problem.

[ljw2k]

Hi, I have a problem with my modified 2D and 3D Maglite ( Both Maglite's have this problem ) as in it quickly gets warm to hot and switches to low mode every 12 seconds then goes on high mode for 5 seconds this is repeated on a 30 minute test I did. I am using a H22A heatsing with an XML LED and a 19mm CC 3000mA LED Driver 3 Modes, 5.5-12v, XM-L,SSC from LCK http://www.lck-led.com/19mm-3000ma-driver-modes-p-501.html?cPath=135 batteries are Kingkong 3.7v 26650 4000mAh Rechargeable Li-ion from http://www.lck-led.com/kingkong-26650-4000mah-rechargeable-p-822.html.

 

[Toaster79]

You should probbably need to pot the driver.

 

[ljw2k]

Hi can you please elaborate " pot the driver " how can this be done please no mention on the site I bought it from that it needs to be potted.

Took the heat sink out of the Maglite and driver turned to high mode and within 4-5 minutes the heatsink was untouchable as hot as an iron is this normal?

I think the heat coming from the heat sink is making the driver go into protect mode and switches it to low but why is the heatsink so hot after so little time the LED is glued to the heat sink with adhesive compound.

I have done many mag lite mods in the past and always used artic silver adhesive compound in the past but this time I am using a cheap one from LCK and can this be the cause of the heat ?

 

[LilKevin715]

Do a google search (top left corner of the page) for "driver potting" there are plenty of threads available to get a general idea. Also in your picture I don't see any thermal paste between the H22A heatsink and the Mag body tube, are you using any?

 

[ljw2k]

Hi, Yes I use thermal paste between the heat sink and the body and it has all been cleaned off before I took the picture.

Running the light on high outside as the picture the driver does not get that hot really so I assume the heat is coming from the heat sink which causes the driver to overheat and prompt it to low mode.

Should the heatsink get so hot though after a few minutes it is untouchable by hand.

 

[monkeyboy]

The driver is overheating and throttling down to low as a safety precaution. Like the others have said, the driver needs to be potted. None of the other components would cause this behaviour, not the unprotected cells you are using or the LED itself, so it is definitely the driver. It has nothing to do with heat transfer from the LED as the driver is not even attached to the heatsink.

Use something like arctic alumina to glue the driver to either the heatsink or the side of the maglite. It doesn't matter which. Make sure all the components on the driver are encased in the glue.

If that doesn't work, use a different driver. Der wichtel's drivers work well without potting

 

[ljw2k]

Thanks MonkeyBoy but the driver stays cool outside the Maglite it is only when I place it inside and the heat from the heatsink must make the driver warm and cause the driver to go into protect mode.

The Maglite never goes into protect mode until it is all placed back together again.

The heat from the heat sink is well and truly hot smoking hot sizzle with wet hands hot.

 

[nmos]

So does the body of the Maglite get hot? It sounds like your heatsink may not be making good enough contact with the tube.

Sent from my ADR6425LVW using Tapatalk 2

 

[ljw2k]

Yup body gets pretty warm especially when I use thermal compound on the heat sink and mag body..

 

[monkeyboy]

I have built several xml maglite builds at 3A and above and none of them get very hot when assembled. Of course the heatsink will get extremely hot when you run the light disassembled as you don't have the surface area of the maglite to dissipate the heat.

Potting the driver will make it run cooler not hotter. A driver gets extremely hot in a small enclosed space surrounded by air. The heat has nowhere to go as air is a good insulator.

 

[ljw2k]

Thanks for the reply Monkeyboy and your reply makes more sense to me now .Can I ask where you get the potting compound in Uk and which you would recommend.

 

[monkeyboy]

I'd use arctic alumina adhesive (make sure you get the adhesive not the thermal compound). Arctic silver is not recommended for driver boards as it is capacitive.

overclockers.co.uk seem to have it in stock although I've never ordered from them before.

Beware that this is not guaranteed to work and you probably won't be able to remove the driver afterwards without destroying it.

 

[ljw2k]

I have recharged all my batteries and they measure 4.2v fresh off the charger , left them for an hour or so before I put them in the 2D Maglite turn to high mode which measures 3A at the LED but the Maglite shuts down to low power and flashes twice every 5 seconds after just 2 minutes on High.Is this the batteries sagging as I don't think it is anything to do with heat as it does it while the driver is inside and outside the torch. On the website it states Lithium-ion battery protection prompt and shut down:When Lithium-ion battery protection, automatically switch to Low mode, and flash 2 times per 5 seconds, shut down after 3 minutes. Please take down Lithium-ion batterys to charge.

• Danger prompt and shut down:

When the flashlight is on high temperature and low voltage, it will flash 3 times per 5 seconds and automatically switch to Low mode, shut down after 3 minutes. Please take down Lithium-ion batterys to charge

 

[Hoop]

Took the heat sink out of the Maglite and driver turned to high mode and within 4-5 minutes the heatsink was untouchable as hot as an iron is this normal?

If the heatsink is out of the mag body it has nowhere to transfer its heat. It will get hotter and hotter. It's purpose is to transfer the heat to the entire mag body to help to dissipate the heat into the air. You need a lot of surface area to effectively dissipate the heat into the air.

 

[ljw2k]

Yes I understand that but the purpose of leaving the heatsink outside the body is so the driver can have cool air, I even had a fan blowing on it to keep it cool but the light still went to low power after 2 minutes and at that time the heatsink was not that hot.I think it's either the driver whats faulty or more so the batteries which can't handle a 3A load for long.

 

[Bucket]

Here is what you need. It's 182 grams of aluminum in two pieces. The inside piece (heat sink) is height adjustable with an allen set screw. The outside piece is just an extension to allow for a larger heat sink. The center post is milled in a milling machine for flatness. The whole thing threads onto the end of the mag and accepts the standard mag head.

Here is a shot of the heat sink by itself.

 

[ljw2k]

Although looks very nice mate I don't think it's what I need , what I need is a new driver or new batteries.

 

[Toaster79]

What batteries are you using? Looks like they're sagging.

 

[ljw2k]

The batteries are in my first link mate http://www.lck-led.com/kingkong-26650-4000mah-rechargeable-p-822.html

 

[Toaster79]

I'd say you've got at least one bad cell there. Try measuring the voltage of each cell under the load.