MUCH IMPROVED:- 2-stage tailswitch heating up on low

[easilyled]

I have a setup in an A19 light as follows:-

GD750CreeQ5-XRE with 17670-lion and 2-stage tailcap (McE2S) with 5-Ohm
resistor.

Only a 5-ohm or at most a 10-ohm will work to provide 2-stages with
this set-up.

I have noticed that on low, the tail-switch heats up quite quickly and after
being on continuously for a few minutes its quite hot.

This doesn't seem to be the case with other drivers such as NG or DB.

So I have 2 questions:-

Is this something that is known with GD drivers?

Does it mean that I shouldn't leave the light on low for long periods?

Any help much appreciated.

 

[mudman cj]

Re: 2-stage tailswitch heating up on low

I have noticed that the GD doesn't handle resistance as well as the other circuits. I can run a NG with 20-30 Ohms for very long runtime and low heat, but the GD is limited as you have noted. It just won't light the LED with that much resistance.

With only 5 Ohms there is probably still over 250mA running through it. If you use about 7 Ohms instead it will reduce the current draw and the heat produced. This is how I run mine. I am using a 22.1 Ohm in parallel with a 10.7 Ohm.

 

[easilyled]

Re: 2-stage tailswitch heating up on low

I have noticed that the GD doesn't handle resistance as well as the other circuits. I can run a NG with 20-30 Ohms for very long runtime and low heat, but the GD is limited as you have noted. It just won't light the LED with that much resistance.

With only 5 Ohms there is probably still over 250mA running through it. If you use about 7 Ohms instead it will reduce the current draw and the heat produced. This is how I run mine. I am using a 22.1 Ohm in parallel with a 10.7 Ohm.

Thanks for the answer. Do you know how I can obtain a 7 Ohm resistor
board for a McE2S? The next one up from a 5 Ohm is a 10 Ohm in the Shoppe,
I think.

 

[mudman cj]

Re: 2-stage tailswitch heating up on low

I am afraid that would have to be a custom job.

 

[easilyled]

Re: 2-stage tailswitch heating up on low

I am afraid that would have to be a custom job.

Ok thanks for the info. :thumbsup: With a 10 Ohm resistor, the tailcap doesn't heat up nearly as much but the low is extremely low.

I'm sure you're right. 7-8 ohms is probably ideal. I might email the Sandwich
Shoppe to see if a custom board is possible for them to do.

 

[Ms_SS]

Re: 2-stage tailswitch heating up on low

We added a choice of 7.5 ohm switch board to the line-up

5, 7.5, 10, 15, 22, 30, 60 ohm resistor boards are available.

 

[easilyled]

Re: 2-stage tailswitch heating up on low

Thanks very much for doing that Cindy.

for two 7.5 ohm resistor boards as per email. :thumbsup:

 

[mudman cj]

Re: 2-stage tailswitch heating up on low

Sweet! Please let me know how you like it.

 

[easilyled]

Re: 2-stage tailswitch heating up on low

Sweet! Please let me know how you like it.

I will do and thanks for the helpful advice. :thumbsup:

 

[easilyled]

Re: 2-stage tailswitch heating up on low

Cindy/Wayne,

The 7.5 ohm resistor boards arrived today. Many thanks for such fast
shipping.

I replaced the existing 5-ohm resistor boards in my McE2S with these new
7.5 ohm resistor boards instead.

This has resulted in the tailswitch heating up far less than it did before
as well as a lower low which is better for preserving night-vision.

I would say that these 7.5 ohm resistor boards are the ideal balance for
single li-ion driving GD-Cree-XRE L.Es (mine is GD750) :thumbsup:

mudman_cj, thanks for the recommendation, I feel much more secure with
this combination. :wave: