KL5 Question...mine stopped working

[ConfederateScott]

I've had my KL5 lighthead for about a year. I was running it on a C3 body with primaries. A few weeks ago I started using rechargeable cells occasionally. Just trying them out. Last night while using Surefire brand primaries the light went kaput. Just stopped working. I got an RMA number from Alex at Surefire this evening and I am returning it. We really didn't discuss what would happen but I wonder if they will repair it (it's the older KL5) or if they'll just replace it with the newer KL5A? Is the KL5A also useable with 3 primaries? Did I do a no-no using the rechargeables? If so, why the wait to stop working AFTER I had used them and was running it on primaries?

 

[Sgt. LED]

I bet they will give you the new KL5A.
As far as your other very good questions go I am not sure so I will keep an eye on this thread and learn something new today.

 

[Kiessling]

The KL5A runs fine on 3xCR123. Mine sits comfortably on a C3.
bernie

 

[Size15's]

The KL5 was designed and intended for two-SF123A batteries.
It could be used with three-SF123A batteries but would operate above regulation until the battery juice dropped sufficiently. Three-SF123A batteries is not an especially good situation for the KL5 and some will handle it better than others. It's to be avoided if possible.

Using rechargeable batteries to power the KL5 is not allowed by SureFire. They may not warranty damaged caused by use of rechargeable batteries. Rechargeable combinations that produce voltage and/or current conditions greater than the standard pair of SF123A batteries produce is likely to present problems.

AFAIK the KL5A is the same. Best use two-SF123A batteries.

 

[thegeek]

Were you using 3 RCR123's or 2 17500 cells? The former case is probably a bit much for that circuit, the latter should be fine.

I'm guessing you will get the new head. I had problems with an old L1 head and after sending it in I now have the new Cree version.

 

[Kiessling]

The KL5 was designed and intended for two-SF123A batteries.
It could be used with three-SF123A batteries but would operate above regulation until the battery juice dropped sufficiently. Three-SF123A batteries is not an especially good situation for the KL5 and some will handle it better than others. It's to be avoided if possible.

WHAT?

Some time back we agreed that 3x123 would be fine.


This post then shows an edit of SF's page:

Anyone know whether the Surefire KL5A head works properly on 3 cells?

The original Surefire KL5A page had:

6P, 9P, C2, C3, G2, G2Z, M2, Z2, Z3

as the supported lights, now shows:

6P, C2, G2, G2Z, M2, Z2

Has there been a new revision?

The product page now reads:
http://www.surefire.com/KL5


So ... was the 3x123 an error on SF's side or did they change the head?

On my Lightmeter the output measures the same on 2x123 and 3x123

:thinking:

bernie

 

[Size15's]

I'm pretty sure that when PK was asked about this some time [perhaps at SS2007] ago (long before the KL5A) he was like - 'Better run it on two batteries rather than three... It'll work with three but it's not ideal as it wasn't specifically designed for two or three batteries'
I'm paraphrasing but that's what I recall.

 

[Kiessling]

But that was for the LuxV version which used a boost converter.
The KL5A should be a buck converter and *could* accomodate the voltage range more easily, but this is just an educated guess.

I'll shoot SF an e-mail.

bernie

 

[Size15's]

Good idea - find out from SureFire directly about the KL5A's ability and suitability to handle three-SF123A batteries.

 

[Kiessling]

Good news:

Dear Sir,
The KL5A can be run with 9V lights with no issues.

Thank you

Greg Lin
Technical Support

So everything is fine and the KL5A feels really well on a C3 😀

bernie
SureFire LLC

 

[Size15's]

Cool.