mosfet issues, suicide watch

[WharfRat1976]

Does it look backwards still?

Do not know if you resolved this but here is my take. I copied and saved your image and blew it up in Photo Gallery:

I see an immediate fail. Start from the GATE of the Mosfet. The GATE side goes to either side of the switch BY ITSELF. You have the POS side of the battery going into the same mount on the switch. The POS side of battery will go to the OTHER side of your switch and then to your 510 pin POS connection.

The DRAIN of the Mosfet goes to the NEG of your 510. That looks good.

The SOURCE of the Mosfet goes to your battery NEG. It's under your board but I assume you have this right.

So change the battery POS to the other side of your switch and run that to your 510 POS and it will be right.

 

[JimmyDB]

Correct me if I am wrong... but if he was bypassing the switch by connecting both leads to the same terminal, then it would always be on and would otherwise work fine,... versus "when an.atty.is installed it barely fires and the mosfet/resistor heat up. " as the OP stated. I would also like to confirm... the point of connecting the battery to the switch is simply to provide the switch with the power required to activate the mosfet (without getting technical).

If you have connected everything the same way it is connected in the diagram it should work, unless something is broken.

Here is an example... yes, the battery is waiting it's turn to go on charge. But the picture shows everything rigged up and that smok ohmmeter is actually showing the voltage passing through the 510 over to the atty on the left.

Now... you will notice the mosfet is attached to a large heat spreader because I wanted the mosfet to be able to handle a lot of power, but in the example picture it's only pushing a couple amps. The mosfets are going to under-rate themselves to a reduced power output once they reach a certain temp (and/or burn out) and it may not be obvious unless you connect an ammeter between the mosfet output and the load (mosfet and 510 or 510 to atty).

Other times I have connected an ammeter between the mosfet and the atty... and the output matched up with the output reading from the power supply that I was using... there was only a slight drop which is accounted for by the mosfet.

Sorry it's so messy, it's parts that were laying around.

 

[WharfRat1976]

Correct me if I am wrong... but if he was bypassing the switch by connecting both leads to the same terminal, then it would always be on and would otherwise work fine,... versus "when an.atty.is installed it barely fires and the mosfet/resistor heat up. " as the OP stated. I would also like to confirm... the point of connecting the battery to the switch is simply to provide the switch with the power required to activate the mosfet (without getting technical).

If you have connected everything the same way it is connected in the diagram it should work, unless something is broken.

Here is an example... yes, the battery is waiting it's turn to go on charge. But the picture shows everything rigged up and that smok ohmmeter is actually showing the voltage passing through the 510 over to the atty on the left.

Now... you will notice the mosfet is attached to a large heat spreader because I wanted the mosfet to be able to handle a lot of power, but in the example picture it's only pushing a couple amps. The mosfets are going to under-rate themselves to a reduced power output once they reach a certain temp (and/or burn out) and it may not be obvious unless you connect an ammeter between the mosfet output and the load (mosfet and 510 or 510 to atty).

Other times I have connected an ammeter between the mosfet and the atty... and the output matched up with the output reading from the power supply that I was using... there was only a slight drop which is accounted for by the mosfet.

Sorry it's so messy, it's parts that were laying around.

Cool little test setup. My point was he did not connect his gear like the diagram. In the diagram there is only one wire from the gate to the switch which is exactly how you wired your test.

 

[JimmyDB]

Cool little test setup. My point was he did not connect his gear like the diagram. In the diagram there is only one wire from the gate to the switch which is exactly how you wired your test.

Thanks!

I realized after I posted this that the battery may look like a button top with the wrapper on wrong... but that's only because I used a magnet to hold the ground lead on. Sadly, I have no 18650 sleds just sitting around

I hope the OP comes back with great news.