64a Switch For Modders

johan

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I had a few enquiries via pm and thought I will post this here for all you Modders. With this graphical circuit you can use any push-to-make (normally open) switch, big or small to achieve up to 64A switching.

64A Mosfet SW.png
 
Where would I be able to purchase all these items to make one. Been toying around with the idea of making a box mod :)
 
Where would I be able to purchase all these items to make one. Been toying around with the idea of making a box mod :)

On the graphic is a link for the Mosfet, the 2 resistors, wires and switch at any electronic shop or also at RS per link.
 
Does this apply only to mech or as well when using a chip?
 
Ω @johan what would you charge to make something like that up for us with the soldering skills of a small bird. Without the switch battery holder and 510?
 
Ω @johan what would you charge to make something like that up for us with the soldering skills of a small bird. Without the switch battery holder and 510?

Kimbo, I have to check prices of the Mosfet 1'st, but it's so simple to solder, I don't know how anybody can charge for that. IMO shipping it will cost more.
 
Hey there Johan is 64A necessary as it is hard to find in the Cape?
 
Hey there Johan is 64A necessary as it is hard to find in the Cape?

No not at all, any logic level low on-resistance mosfet (n-channel) will do. The IRL3103 was chosen for its very low on-resistance for minimal voltage drop. Can even use P-channel logic level mosfet, but need to reverse polarity in the circuit.
 
Thanks Johan,

Just to be clear a 5oA, 60V n-channel mosfet transistor will do the trick?
 
Thanks Johan,

Just to be clear a 5oA, 60V n-channel mosfet transistor will do the trick?

Yes more than enough, just make sure its a logic level mosfet ..... a standard mosfet needs about 15V to "fully" switch ON, whereas logic levels "fully" switch ON at 3V.
 
Hey there Johan

One last question, where could I pick up a bottom fed 510 connector?

Thanks
Robert
 
Hey Johan

The switch I am building is 72amp how low a build would i safely be able to
use with this in mind?
 
Hey there Johan

One last question, where could I pick up a bottom fed 510 connector?

Thanks
Robert
fatdaddyvapes.com I also want to order, just waiting for this post office strike to end.
 
Hey Johan

The switch I am building is 72amp how low a build would i safely be able to
use with this in mind?

Here is all the calculations you'll ever need (you know your battery voltage and you know your max current):

Note:
1. Assuming you use a battery that can safely discharge 72A (haven't seen them in 18650 size), but lets say you parallel connect 3 VTC5 18650 batteries:

R = V/I
R = 4.2V/72A
R = 0.058 Ohm

If your battery is only rated at i.e 25A discharge current then:

R = V/I
R = 4.2V/25
R = 0.168 Ohm


ohms-watts_law.jpg
 
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