Diy box mod question with volt meter.

[FictitiousFreedom]

I finished my first diy box mod the other day. I learned a lot and am extremely surprised at how well it works.

I started wanting a mosfet, 2 15 amp fuses, an on off switch, and a volt meter. Being my first box i had to do a lot of research. I already know how to solder but know very little about electrical components so i had a lot of problems.

I worked on this for a few hours before finishing. It dIdn't work. so i started by going over all my connections to try and find the problem and after removing the volt meter and the on off switch it still didn't work sooo i ordered another mosfet assuming i ruined the first one.

After soldering in my second mosfet it still wouldn't work, so i removed the fuses and it worked. So now i have a working box but without the fuses, on off switch, or the volt meter. It works great, surprisingly great.

Im going to order more stuff and make a few more before trying a raptor and more advanced boxs.

My question is, how can i wire the volt meter in? I attempted to just test it by touching the leads to the switch and lead coming from the mosfet gate and almost ruined my device. Also there are 2 20awg wires coming from the volt meter, can i just solder one lead to the gate and put the other lead in the switch? Or do i need to run the 16awg from the meter to the switch?

I know this is confusing and im going to post pictures of the mod and the meter, any help would be much appreciated. I don't want to just attempt this without some information because im really loving the way this box performs and don't want to ruin it.

 

[FictitiousFreedom]

 

[david4500]

You can connect your voltmeter either of two different ways:

#1 - Positive to the vout side of your fire switch or mosfet gate. Negative to battery negative or mosfet source. Pressing the fire switch, the voltmeter will display with or without an atomizer attached.

or

#2 - Positive to 510 positive pin or battery positive (after fuses if using them). Negative to 510 negative ring or mosfet drain. The voltmeter will only display when the fire button is pressed with an atomizer attached.

Here's a drawing showing the first option:

 

[FictitiousFreedom]

Awesome, thanks. So i need one between the gate and the switch and the other between the source and battery connection.

Can i solder it straight to the battery connection where the source is or does it need to be soldered on the source wire? Same question with the gate, does it have to be soldered in between the gate and switch or can i just connect it straight too the switch?
Thanks!

 

[david4500]

Connect at the gate, switch or anywhere between.

Connect at the source, battery negative contacts, or anywhere between.

 

[FictitiousFreedom]

Thanks for the help!
I notiCed after i soldered to the source i could complete the connection on any part of the box so i connected between the switch and 510 so the meter would always stay on, so that i could see battery life, this would be better if i had a master on/off switch but it works.

I was curious as to how much battery the volt meter would use just by leaving batteries in all night and to my surprise it only lost around 0.02 volts in 8 hours.

Again thanks for the help, my next box should be much better, those damn fuses are just a pita to get right.

 

[FictitiousFreedom]

Also, i can't believe how much battery life i get, im using a battery draining build, a dual 22g 9 wrap build at around .28 ohms, in a mech a battery would be noticeably sagging in less than an hour, with this 2 batteries will stay above 3.5v for close to 5 hours. Amazing, also my voltage drop with this build is around 0.3. Im super impressed with how this performs. I just need to find a more comfortable enclosure, im used to my vapor flask. I may pick up a clone and try to make it into a mosfet mod.