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McC2S, how much current?

abuhannibal

Newly Enlightened
Joined
May 18, 2008
Messages
83
Location
Israel
Will the McC2S handle enough current to be used with a direct-drive P7 or MC-E? I am thinking of using one with my new Milkyspit roomsweeper (Leef C-C 2x18500 body, Milky-modded C2 head with an MC-E.)

The plan would be to only hit the max output for a few seconds at a time, say half a minute at most.


Thanks!

-- Bob
 

Ms_SS

Enlightened
Joined
Mar 28, 2004
Messages
435
Location
CA
Please ask on the McGizmo forum since Don designed and knows this stuff.
Then please post your answer here so we all know.
 

Chrontius

Flashlight Enthusiast
Joined
Oct 11, 2007
Messages
2,150
Location
Orlando, FL
Can you give even a rough estimate for the McE2s and the McC2s?

I'd be more worried about the surface-mount resistor eating itself on low beam, honestly.
 

dat2zip

Flashlight Enthusiast
Joined
Jan 5, 2002
Messages
3,420
Location
Bay Area
The resistors used are 1206 and in most cases we use two resistors to get the desired resistance. Each resistor has 1/2 the total power loss across the switch. A standard 1206 resistor is rated for 0.25W. Together two resistors is ~0.5W.

Industry standard practice is to derate resistors by 1/2 of the specified wattage. This puts the two resistors at a safe 0.25W.

Power across the two resistors if you know the current is:

Current^2 * Resistance = Watts.

A 60 ohm switch uses two 120 resistors. (use 60 ohms in the equation).

Working backwards re-arranging the formula we compute the max current as:

0.25W / 60 ohms = max_current^2 = 64mA

For other resistor values you will have to plug them into the equations to determine the max current.

Wayne
 
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