Raptor Flip-Top VV Mod with 20A, 120W dc/dc converter...

[mamu]

I got the LG batts I ordered yesterday. Came off the charger at 8.6v so that was curious (I didn't measure them individually - just used the Raptor's input volts reading - wish I had measured them individually now).

Been vaping with them since yesterday morning on the Raptor. So far, 0.0 volts drop loaded output, 0.3 volts drop loaded input initially, but now 0.2 volts drop input and still 0.0 volts drop output. This morning it was at 8.3v and that was after about 24 hours of vaping. Right now reading 7.8 volts input unloaded (7.6v loaded).

Will update what the cutoff unloaded voltage is. But that will be a while. woot!!

 

[bapgood]

I got the LG batts I ordered yesterday. Came off the charger at 8.6v so that was curious (I didn't measure them individually - just used the Raptor's input volts reading - wish I had measured them individually now).

Been vaping with them since yesterday morning on the Raptor. So far, 0.0 volts drop loaded output, 0.3 volts drop loaded input initially, but now 0.2 volts drop input and still 0.0 volts drop output. This morning it was at 8.3v and that was after about 24 hours of vaping. Right now reading 7.8 volts input unloaded (7.6v loaded).

Will update what the cutoff unloaded voltage is. But that will be a while. woot!!

I'm ready to hear what you think about the LG's!!!

Mine aren't moving very fast

 

[mamu]

Still vaping with them on the first charge.

So far 0.2v - 0.4v range for input drop and 0.0v for output drop.

Wish I had bought more everyone seems to be sold out now.

 

[bapgood]

Still vaping with them on the first charge.

So far 0.2v - 0.4v range for input drop and 0.0v for output drop.

Wish I had bought more everyone seems to be sold out now.

My LG's have hit the main land

Hopefully by the end of the week....fingers crossed


I talked to this ebay seller Batteries items in RL-batterydepot store on eBay! about if and when he was getting the LG's

And he said "should arrive at distributors around the middle of January. Then it will take a bit from there to arrive to me."

 

[BJ43]

Mamu, I am really enjoying my Raptor and am ordering another one... I have a question, I would like to go a little higher on the output voltage. To get up to 7v, would I need to go to 11.1v lipo a different resistor and an 8.6v diode to cutoff at 9v?

 

[BJ43]

My Raptor with 4200 mAh 65C lipo. 1.3 ohm, 17.6 w 5.1v. Look at the imput drop only .04. On all my mods with 18650 my imput drop has always been in the .2 to .4 range, i have never seen .04. clic pic for video

 

[mamu]

Well done BJ!

Only 0.04v input drop is awesome.

Mamu, I am really enjoying my Raptor and am ordering another one... I have a question, I would like to go a little higher on the output voltage. To get up to 7v, would I need to go to 11.1v lipo a different resistor and an 8.6v diode to cutoff at 9v?

I'm curious as to why you would want to take the converter out of spec and run it at a higher than manufacturer recommended output voltage? A better choice would be to lower the resistance of your coil to get a comparable vaping power that the 7v would give you.

With these converters, you never know what the tolerances are with the onboard components. Running over max spec may cause an unstable, unreliable response or pop one or more components that don't have the tolerance to run out of spec.

Anyway, if you choose to do it, replace the 220 ohm resister and 200 ohm POT with a 185 ohm resister and a 250 ohm POT to get a range of 3.3v - 7v.

Yes for using a 8.6v zener and 11.1v lipo pack (fully charged 3S lipos are 12.6v so you're within max input voltage spec there).

Theoretically this should work, but as I've not directly done it will be curious as to how it turns out for you if you choose to do it.

 

[BJ43]

Well done BJ!
I'm curious as to why you would want to take the converter out of spec and run it at a higher than manufacturer recommended output voltage? A better choice would be to lower the resistance of your coil to get a comparable vaping power that the 7v would give you.

I have been concentrating on vertical coils in Russian type RBAs with all the air being drawn thru the coil and hemp fiber around the coil. I am using mostly R41 wire. The lower the ohms the smaller the vapor producing area on the coil. So my 1.3 ohm at 17/18watts 5v is great, if I go higher to produce more vapor it gets too hot and bad flavor. If I use the same wire with more wraps 2 ohms to produce more vapor and at 6v I get the 18watts but spread out over a larger area is less vapor and flavor, so to get the equivalent flavor with more vapor I need to pump up the 2ohm to around 22 watts. I really had not seen that the Raptor was limited to 6v. Anyway I am just playing with my coils and hemp and have a large amp bench PV that I can pump up for testing. Do plan to build a Raptor passthru for my truck and just use the trucks 12v system. Will probably break down and do some dual coils to get the larger area with low ohms.

 

[Alexander Mundy]

BJ, you might or might not run into trouble running off vehicle power. Absolute max input is listed at 14V. Course they say it might go higher, but might go poof. Vehicle alternators can and often do spike above 14V.

 

[BJ43]

Ok, third day on the 4200mAh lipo, waiting for the diode to stop me. Input showing 7v and 6.95v under load, 5v output, The screen was on output and all of a sudden it flashed and went off. When I switched to imput it showed 5.51v.. So put it on my charger, cell 1 was 2.68v and cell 2 was 2.83v. Needless to say they had to be jump started. Don't know why the diode let it get so low, but i will be looking for a diode that will cut out at 7v. Battery is now charging normal.

 

[bapgood]

Ok, third day on the 4200mAh lipo, waiting for the diode to stop me. Input showing 7v and 6.95v under load, 5v output, The screen was on output and all of a sudden it flashed and went off. When I switched to imput it showed 5.51v.. So put it on my charger, cell 1 was 2.68v and cell 2 was 2.83v. Needless to say they had to be jump started. Don't know why the diode let it get so low, but i will be looking for a diode that will cut out at 7v. Battery is now charging normal.

That is odd!!! I'll be interested to hear how it does going forward, you really shouldn't have to worry about cutting off at 7v. Those cells shouldn't be bothered by any load that the raptor is possible of producing. ?????

 

[Alexander Mundy]

A zener diode has to have a certain level of bias current to clamp at the rated voltage.
The data sheet shows the enable input has a 7K5 resistor in series with the enable pin and a 100K past the 7K5 to ground.
Mamu has added a 7K5 resistor in parallel so along with the internal resistors this will bias the diode with about .86 mA plus whatever little bit the circuitry past the input resistors puts on it.
While Mamu's zener might be happy with that, the zener you are using might not be above the knee of the bias curve with this amount of bias current.

^^^^^^^^^
Brain fart. If the diode wasn't conducting the module wouldn't enable.

Also, what is the tolerance of the zener you are using.
If it is 5% it could be as low as 5.32V up to 5.88V.
And the data sheet shows a .6V spread from .4V to 1V for the enable pin where maybe it is on and maybe it is off.

Just thoughts I had that might explain

 

[BJ43]

Thinking of replacing the 5.6v for a 6.2v diode 1N5234C

http://www.fairchildsemi.com/ds/1N/1N5234C.pdf

 

[mamu]

I'm not sure exactly what's going on there, BJ. Mine consistently cuts off at 6v loaded with both the Sony (unloaded 6.2v) and the LG (unloaded 6.4v) batts.

If I'm monitoring the output voltage near input cutoff voltage, the voltage reader starts flickering and flashing (converter is pulsing and not outputting).

Yes, in your situation it would be best to up the zener's breakdown voltage. Let me know how it goes.

 

[Visus]

Do plan to build a Raptor passthru for my truck and just use the trucks 12v system. Will probably break down and do some dual coils to get the larger area with low ohms.

Bj has just pulled up

 

[BJ43]

I'm not sure exactly what's going on there, BJ. Mine consistently cuts off at 6v loaded with both the Sony (unloaded 6.2v) and the LG (unloaded 6.4v) batts.

If I'm monitoring the output voltage near input cutoff voltage, the voltage reader starts flickering and flashing (converter is pulsing and not outputting).

Yes, in your situation it would be best to up the zener's breakdown voltage. Let me know how it goes.

Strange, mine did the same. I was monitoring output it flickered and flashed, then when I ck input it is at 5.51v. Are the other parameters of the 6.2v diode I want to use OK? I am no electronics wiz..

 

[mamu]

The specs look good for the 6.2v zener you've chosen, BJ. Both low impedance and low power dissipation.

I re-read your previous post and I'm trying to wrap my head around what you said.

You said, "Input showing 7v and 6.95v under load, 5v output, The screen was on output and all of a sudden it flashed and went off. When I switched to imput it showed 5.51v..."

Something's not right if it previously showed 7v then showed 5.51v when you re-checked it. It sounds like there was an unexpected current dump from the battery as you don't in normal operation get that large of a difference in input voltage in that short of a time period. Unless I'm misunderstanding what you mean?

You said "The screen was on output and all of a sudden it flashed and went off". So I'm thinking an unexpected short somewhere. It shouldn't all of a sudden flash and then blank out. I've not had the screen blank out, it just flickers when the input voltage is not handling the load and I get a wushy hit with very little vapor production.

Ok, third day on the 4200mAh lipo, waiting for the diode to stop me. Input showing 7v and 6.95v under load, 5v output, The screen was on output and all of a sudden it flashed and went off. When I switched to imput it showed 5.51v.. So put it on my charger, cell 1 was 2.68v and cell 2 was 2.83v. Needless to say they had to be jump started. Don't know why the diode let it get so low, but i will be looking for a diode that will cut out at 7v. Battery is now charging normal.

 

[BJ43]

The specs look good for the 6.2v zener you've chosen, BJ. Both low impedance and low power dissipation.

I re-read your previous post and I'm trying to wrap my head around what you said.

You said, "Input showing 7v and 6.95v under load, 5v output, The screen was on output and all of a sudden it flashed and went off. When I switched to imput it showed 5.51v..."

Something's not right if it previously showed 7v then showed 5.51v when you re-checked it. It sounds like there was an unexpected current dump from the battery as you don't in normal operation get that large of a difference in input voltage in that short of a time period. Unless I'm misunderstanding what you mean?

You said "The screen was on output and all of a sudden it flashed and went off". So I'm thinking an unexpected short somewhere. It shouldn't all of a sudden flash and then blank out. I've not had the screen blank out, it just flickers when the input voltage is not handling the load and I get a wushy hit with very little vapor production.

It was maybe half an hour since I had ck the imput before it started to flash and flicker on output. Anyway I ck all possible shorts and am giving it another test before switching diodes.

 

[b0bl0blaw]

Hey Mamu! Any specific specs for the 220 ohm and 7.5K ohm resisters? Can you link to an example on mouser or digikey?

Thanks!

 

[bapgood]

Hey Mamu! Any specific specs for the 220 ohm and 7.5K ohm resisters? Can you link to an example on mouser or digikey?

Thanks!

What your looking for is in the OP .....EDIT.....Sorry I thought there was part numbers for the resistors