Current Capability of 2-way twistie tailcap approx 2005

[lemlux]

Hi, Don:

I have a couple of your better e-series mechanical 2-level twistie tailcaps of cerca 2005 vintage. I bought them at the same time I bought a few of your 2*123 and 3*123 bodies which use a lower current screw-in on off button cap (Kroll?) designed for the mag 2aa (if that helps pin down the dating.)

I recall seeing a drawing of the mechanical compression of the tailcap that progresses the light from low level to high output either with momentary and twist execution.

I would like to use this tailcap on a P60 "linger special" drop-in made by Nailbender which incorporates a pair of XP-G emitters driven by a 1-level regulated 2.8 A board that can handle 3.6 to 6 Volts input. Is your vintage tailcap capable of handling the 2.8 A current for an extended period? If not, what is its current limitation?

Thanks.

 

[lemlux]

Searches have revealed that the low level is resistored, but I still don't know the current handling capability.

 

[fyrstormer]

I suppose if you really wanted to know, you could use a Li-Ion battery and a multimeter to test the amperage of a circuit involving just the battery, the meter, and the low mode of the switch. The battery will have more than enough amperage to max-out the capacity of the switch, but it wouldn't be a short-circuit because of the presence of the resistor.

 

[McGizmo]

I would guess that you would need to put new resistors on the PCB capable of handling the expected current. Their actual capacity varied as based on the size and number of resistors used but they certainly were not selected and used with target current you now wish to subject them to.

 

[fyrstormer]

My own understanding of the two-mode switches is rather limited as I only ever owned one personally. Don, if you wouldn't mind clarifying:

1. Is the high-mode resistored or is it a direct pass-through, or is it sometimes one or the other depending on the exact build of the switch?

2. Do the resistor(s) in the switch perform their intended function by reducing the voltage going into the driver, forcing the driver to work harder and less efficiently; or by limiting the maximum current flow to a level below that which the driver would pull if it had direct access to the battery?

3. What is the overall impact of impeding the power supply on the driver's operation? Does it run hotter? Is the induction coil put under more stress? Given high enough resistance, does the output voltage drop below the spec for the driver?

Ultimately I'm just curious, but the answers may help the OP as well.