VapCap DIY Induction Heating : Bits 'n' pieces

stardustsailor

Well-Known Member
Accessory Maker
Advanced DIY IH device

Using the " 5-12V ZVS IH module " and the " 15A 400W MOSFET Switch ".
Designed to be powered with a PDA 12VDC / 10A external / wall plug PSU or with
a " 3x 18650 Li-ion battery cell pack with 12 V / 10 A BMS protection board " .

It features a 10A fast fuse ( as short circuit / overload protection ),
working coil thermal protection and
a debouncing circuit for the activating push -button /tactile switch .


"Switch debounce pcb " size : 10.1 x 11.5 mm

GND and OUT pads accept 2x standard pitch -2.54 mm - male header pins ,
at 5.08 distance (pin - empty -pin ).
https://www.amazon.co.uk/2-54mm-20mm-Long-Header-Pins/dp/B00U8R3Y2G

thus the small pcb can be directly connected to the" 15A 400W MOSFET switch "module ,
by soldering it's "GND" and "OUT " pins to the "GND" & "TRIGGER" through-hole pads
of the MOSFET switch module ,respectively .



 
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stardustsailor

Well-Known Member
Accessory Maker
The Ideal MOSFET
for the
" 5-12 Volt ZVS Induction Heating Driver Module "
( Resonant Frequency : 182 kHz )

OR
any other 100-150 Watt DIY ZVS IH design
with 12 VDC
Max. Supply Voltage


- Because of the resonant voltage rise in the primary, the FET drains must withstand more than 2 times the power supply voltage. Most designs recommend a voltage rating of 3 to 4 times the supply voltage.
For a supply voltage of 12 Volts, the FETs should be rated conservatively at
40 Volts or higher ( VDS ).

- Because of the resonant current rise in the primary, the FETs must be able to handle currents about 4 times the nominal power supply current ( ID cont.> 40 Α ) . This requirement is normally satisfied by selecting FETs that have high continuous drain currents and RDS(on) resistances of less than ten milliohms ( RDS(on) < 10mΩ ).

- Another consideration for the FETs is the gate to source capacitance ( gate charge QGS ), which should be minimized to improve FET turn-on and minimize FET dissipation.

- High-Q resonant circuits can store considerable energy in their inductance and capacitance. Under certain conditions, this high energy causes the current to freewheel through the internal body diodes of the MOSFETs as one MOSFET turns off and the other turns on. (An intrinsic body diode is formed in the body-drain p-n junction connected between the drain and source. In N-channel devices, the body diode anode connects to the drain. The polarity is reversed in P-channel MOSFETs.) A problem can arise because of the slow turn-off (or reverse recovery) of the internal body diode when the opposing MOSFET tries to turn on. Thus ,Reverse Recovery time ( Trr ) & Reverse recovery charge ( Qrr ) should be kept as short & small as possible ( Trr < 50 nS & Qrr < 50 nC )

Six variables are to be considered firstly :


1 ) VDS >= 40 V
2 ) ID cont. >= 40 Α
3 ) RDS(on) =< 10mΩ
4 ) QGS =< 25 nC

5 ) Trr =< 50 nS
6 ) Qrr =< 50 nC



Sources :
https://www.powerelectronictips.com/how-and-when-mosfets-blow-up/

http://www.kiblerelectronics.com/bob/app_notes/note11/note11.html

https://www.mouser.com/pdfdocs/Vishay_Zero_Voltage_Switching.pdf

https://www.fairchildsemi.com/application-notes/AN/AN-9725.pdf

https://www.st.com/content/ccc/resource/sales_and_marketing/promotional_material/magazine/7a/dd/a6/78/0f/a7/49/5d/TP 1033 Why use a fast diode MOSFET in a LLC.pdf/files/TP 1033 Why use a fast diode MOSFET in a LLC.pdf/jcr:content/translations/en.TP 1033 Why use a fast diode MOSFET in a LLC.pdf

https://www.electronicdesign.com/po...sfet-tailored-zero-voltage-switching-supplies

https://www.fairchildsemi.com/application-notes/AN/AN-9067.pdf

https://pdfs.semanticscholar.org/f2cb/f62a341df219ee6a47b498b7dfe387f91d4d.pdf
 
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stardustsailor

Well-Known Member
Accessory Maker
An updated IH "advanced " circuit .



The only difference with the previous one is that at the updated circuit the "switch debounce "
sub -circuit is now powered directly from the power source and not via the thermal breaker protection .

At the latter case ,if the thermal breaker trips ,it shuts down the MOSFET switch ,but at the
same time it also shuts down the switch debouncing circuit ,
thus there's no noise filtering at the moment of shutting down .

At the new /updated circuit the switch debouncing circuit remains active ,even if the
MOSFET switch "trigger" has been shut down ,from the thermal breaker tripping .


Note : if the push button is pressed and it's LED will remain OFF ,then it can mean two things :
1 ) Either the thermal breaker has tripped
OR
2 ) There's a possible malfunction/fail at the MOSFET Switch .
AT both cases the IH device can not be activated.

If from the other hand ,the LED lights up when the push button is pressed ,
but the IH device will not operate ,then the ZVS IH module is malfunctioning or has failed .


Have a great weekend .
Cheers.

 
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stardustsailor

Well-Known Member
Accessory Maker
A new and updated "switch debouncing sub-circuit " pcb
With the use of a 3x header pin ( pin-empty-pin ) at the GND and OUT pads,
it can be soldered directly on top of the 15A 400W MOSFET switch module
and save quite some space ( " IN " goes to " TRIGGER" & GND to GND ).





For those of you that can make your own DIY pcb ( with the laser printer stencil method or other),
here's the pcb .dip file :

https://drive.google.com/open?id=1VWZ7Q6i8tyO97rwDP-niNtQga6_RXc1H


It can be opened and further processed with the DipTrace Schematic & PCB Designing software .
You can download the freeware version of DipTrace here
-as also language pacs,3D component STEP models ,component libraries ,etc - :

https://diptrace.com/download/download-diptrace/
 

stardustsailor

Well-Known Member
Accessory Maker
The inductance of the oem work coil of the "5-12 V ZVS IH driver " is 1162.369 nH .
The total capacitance of the two caps is 660 nF .

http://fuckcombustion.com/threads/v...ating-bits-n-pieces.33216/page-2#post-1309601

*****



https://www.translatorscafe.com/unit-converter/en/calculator/parallel-lc-impedance/

*****


VRMS = Vpeak / √2 = >
12 / 1.414 = ~8.5 V

iL = vL/XL = 8.5/1.32709 = ~6.4 A
iC = vC/XC = 8.5/1.32709 = ~6.4 A

*****
When XL = XC and the same voltage is applied to both components, their currents are equal as well. Therefore the difference is zero, and no current is drawn from the source. This corresponds to an infinite impedance, or an open circuit.​

This doesn't mean that no current flows through L and C. Rather, all of the current flowing through these components is simply circulating back and forth between them without involving the source at all.
The currents calculated with Ohm's Law still flow through L and C, but remain confined to these two components alone. As a result of this behavior, the parallel LC circuit is often called a "tank" circuit, because it holds this circulating current without releasing it.

There is one other factor to consider when working with an LC tank circuit: the magnitude of the circulating current. We can use many different values of L and C to set any given resonant frequency.

As long as the product L × C remains the same, the resonant frequency is the same.

calc-parallel-LC-impedance-f4.svg.png


However, if we use a large value of L and a small value of C, their reactances will be high and the amount of current circulating in the tank will be small. If we reverse that and use a low value of L and a high value of C, their reactances will be low and the amount of current circulating in the tank will be much greater.

Many applications of this type of circuit depend on the amount of circulating current as well as the resonant frequency, so you need to be aware of this factor. In fact, in real-world circuits that cannot avoid having some resistance (especially in L), it is possible to have such a high circulating current that the energy lost in R (p = i²R) is sufficient to cause L to burn up!

http://www.play-hookey.com/ac_theory/randr/ac_lc_parallel.html

*****
For
Vpeak =12 V

I Lpeak = Vpeak / XL = 12 / 1.32 = 9.09 A
I Cpeak = Vpeak / XC = 12 / 1.32 = 9.09 A




___________________________________________________________________________

For the 11 turn / 25 mm long ( modified ) work coil :



For
Vpeak =12 V


I L peak = Vpeak / XL = 12 / 1.33= 9.015 A
I C peak = Vpeak / XC = 12 / 1.33 = 9.015 A

 
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stardustsailor

Well-Known Member
Accessory Maker
Switch Debounce II ( Regulator Version )

Parts used
:

1x LM1117-05 , Voltage Regulator I.C. / SOT-223
2x 10μF , Tantalum capacitors / SMD C6032
1x MAX 6816 EUS+T , Mech. Switch Debounce I.C. / SOT-143

*****

Shop parts :

For 5x pcs switch debounce modules ( price for components only ) : $10 ( $2 per module )

https://www.ebay.com/itm/5X-KABA-MA...530415?hash=item2ab5c9d76f:g:6RQAAOSwb4VbnzWH

https://www.ebay.com/itm/20PCS-AMS1117-LM1117-5V-1A-SOT-223-Voltage-Regulator-NEW/323172207859?ssPageName=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649

https://www.ebay.com/itm/10PCS-NEW-10UF-35V-C6032-Type-C-Tantalum-Capacitor-SMD-C-6032-Chip-CA-NEW/142314019809?ssPageName=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649

*****

Schematics / PCB
:





( dimensions given in mm )




DipTrace PCB file
:

https://drive.google.com/open?id=1LvSGjeH2KnRp-PoOwfOnZ7bNr2vX0xPO
 
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stardustsailor

Well-Known Member
Accessory Maker
A very good large diameter ( 19 mm ) push -button with LED .

https://www.banggood.com/12V-5-Pin-...tch-Sliver-p-1181527.html?rmmds=search&ID=229

https://www.e-switch.com/system/asset/product_line/data_sheet/5/PV4.pdf

Has a distinct "click " action and it's overall quality is quite high for the price
(similar push buttons .the "anti-vandal " kind , are quite pricey )

It also has a dedicated plug :https://www.banggood.com/Socket-Plu...-Socket-Connector-p-1143368.html?rmmds=search

But the total length ( switch + plug ) is close to 5.5 cm ( ~ 2 " )
and it's not easy to fit inside a small box / case .


The diameter of the switch body is 19 mm .
I can only drill holes of 20 mm -on the case .
So I had to improvise in order for the switch ,
to sit nicely on the 20 mm hole of the case ,not being off- center .

A M18 stainless steel washer ( 304 SS ) has an inner hole diameter of 19 mm !
A bit of work on the lathe to reduce it's outer diameter and do some grooves .
A bit of polishing and :



I picked a switch with blue LED illumination
,as also the rest of the forthcoming new IH device's LEDs are all blue .



 
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stardustsailor

Well-Known Member
Accessory Maker
Right now I've only one .
I'm planning on making a second one .

I'm not quite sure if I should make them for selling .
There are other makers / FC members ,who make very-very nice portables
and I'm not planning to be a "competitor "to them .

If I will eventually make more for others ,they will be supplied with a PDA wall adapter only .
"Desk-top Induction heaters for the VC ".And most probably will be available only within EU .

Not so portable like the battery-powered ones ,
but they do have their advantages over the former ones.
 

Diggy Smalls

Notorious
Oh, okay...so this is an evolving project of one vaporizer. I get it much more now. I was imagining all these induction heaters laying around your house, but you're just modifying the one. Well, it is very cool. I have no idea how much it would cost, but it seems like it's becoming quite the high end device. I really like that textured metal you have on the underside of the enclosure. That button with the light is going to look killer.
 

stardustsailor

Well-Known Member
Accessory Maker
Oh, okay...so this is an evolving project of one vaporizer. I get it much more now. I was imagining all these induction heaters laying around your house, but you're just modifying the one. Well, it is very cool. I have no idea how much it would cost, but it seems like it's becoming quite the high end device. I really like that textured metal you have on the underside of the enclosure. That button with the light is going to look killer.

Yes ,it's an evolving project .
Actually I've plenty of IH parts laying around my house ,
but yes I'm only modifying the prototype.

If eventually I will start making them for selling ,
price is going to be less than 100 € ( IH device + PDA PSU 12 VDC / 10 A ) ,
without shipping fees.

This texture was done with a diamond bit and a Dremel
and it's actually very easy to do but also a very time-consuming procedure .

Cheers.
 

stardustsailor

Well-Known Member
Accessory Maker

mr_cfromcali

Accessory Maker
Accessory Maker

Wow, @stardustsailor - a new debounce circuit?! If I may ask, how does this one differ from the previous one? I just ordered the parts and a small run of PCBs for the other circuit on Friday, so I am very curious, lol. In any event, THANK YOU!!! for sharing your innovations with the rest of us! :tup::love:
 

pxl_jockey

Just a dude
If I will eventually make more for others ,they will be supplied with a PDA wall adapter only .
"Desk-top Induction heaters for the VC ".And most probably will be available only within EU .

If eventually I will start making them for selling ,
price is going to be less than 100 € ( IH device + PDA PSU 12 VDC / 10 A ) ,
without shipping fees.

Hell yeah! :rockon: In your face @Diggy Smalls LOL, no SDS EU IH for you colonials*! Sorry dude, that’s not nice and you’re always so kind and then I gotta go and make fun because of your time zone. Time zone bullying is among the worst types of bullying. I’m ashamed, my friend. Sorry.

Please @stardustsailor do this! Make at least one more unit, please!! And then sell it to me. :brow: I would love ya even more than I already do! Given my current health I’m at home so much that the idea of a beautiful tethered unit is quite appealing. Think about it? Please?

* Once while chatting with a posh elderly English lady, she actually called me a colonial in a rather condescending manner. I was shocked honestly for a split second but realised that in her dry aristocratic way, she was just fucking with me! She was so pleased when I played along with a straight face. :lol:
 

stardustsailor

Well-Known Member
Accessory Maker
It's not a debounce circuit ...only.

It's a MOSFET Switch module
( actually it uses the exact same MOSFETs like the "15A -400Watt Mosfet Switch Module " ),
but having a build-in debouncing circuit .
The debounce circuitry itself is powered by a LM1117 -05 voltage regulator
(fixed output voltage is 5 VDC ) this time and not from a resistor -zener diode combo.
 
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stardustsailor

Well-Known Member
Accessory Maker
Hell yeah! :rockon: In your face @Diggy Smalls LOL, no SDS EU IH for you colonials*! Sorry dude, that’s not nice and you’re always so kind and then I gotta go and make fun because of your time zone. Time zone bullying is among the worst types of bullying. I’m ashamed, my friend. Sorry.

Please @stardustsailor do this! Make at least one more unit, please!! And then sell it to me. :brow: I would love ya even more than I already do! Given my current health I’m at home so much that the idea of a beautiful tethered unit is quite appealing. Think about it? Please?

* Once while chatting with a posh elderly English lady, she actually called me a colonial in a rather condescending manner. I was shocked honestly for a split second but realised that in her dry aristocratic way, she was just fucking with me! She was so pleased when I played along with a straight face. :lol:

With your utilisation of the words " Given my current health" ,
you must 've pressed some kind of button within me.
:hmm:

Ok ,then .
I will be making two units in the next couple of weeks (or so ) .
One is reserved for you ,if of course you will still have the wish for it .
No strings attached on this matter.

Cheers.
 

stardustsailor

Well-Known Member
Accessory Maker
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