Where To Get "Free" TO-247 IGBTs and MOSFETs

[Mads Barnkob]

A look at a box of IGBTs and MOSFETs that I have salvaged from household electronics like microwave ovens, induction stoves, solar inverters, welding machines, car and battery charges and other common high power electronics with switching inverters.

Do you have any sources for salvaging IGBTs / MOSFETs that is widely available from "household" items?

[ZakW]

Hey Mads,

I don't have a household source but I am fortunate to work for an ISP in my area. I am friends with the warehouse who handles recycling old equipment so every now and again i go take a look at what they have. There is usually a huge crate (5ft cubed) full of all kinds of PCBs. I have built up a nice stock of heasinks, MOSFETs, and misc diodes.

[Max]

As I commented on youtube, SMA solar inverters are popular here around. The models that are now slowly being retired/failing (a.k.a. the stuff that shows up for cheap or free) are just full of salvageable parts. Unfortunately, more recent models seem to be less salvage-friendly; f.ex. one we got installed in our house has the heatsink integrated into the casing. They're also noticeably smaller now.
Anyways, those older ones only contain the good, expensive name brand stuff. TI opamps, Avago opto-isolated gate drivers, big made-in-germany inductors, huge heatsinks, silicone cables, WAGO connectors, ... Even the unisolated faston crimp contacts all the wires give you immediately a feel of quality (it's the type with latch like these).
Also, all SMD parts on all PCBs were conformally coated.

Below the picture I included a list of everything I salvaged out of a 4 or 5kW unit whose bus capacitors blew up (MOSFETs and IGBTs seem fine). I didn't do any sort of reverse engineering but it is interesting to note that the main inverter apparently uses 1200V MOSFETs, not IGBTs.

Kind regards,
Max

• Passives
• Bunch of good quality WIMA and EPCOS foil capacitors (top right)
• 4x EPCOS 680uF 450V (possibly bad condition, since some of them blew up (cf PCB))
• 3x 2x2.8mH 10A 250V EPCOS Common Mode Choke Product Link
  
• 3x "small", 2x large inductors - all made in germany by SMP. The small ones are likely associated to each of the three solar DC inputs, the larger ones likely related to the single phase AC output. Based on another, similar inductor from another SMA unit, the big inductors are in the ballpark of 2mH 25A.
• Sensors
• 3x +/-10A 50kHz BW Current transducers Product Link
  
• 1x +/-25A 250kHz BW Current sensor Product Link
• ICs
• Bunch of logic ICs (74HC/AHC)
• 7x LM258 OpAmp Dual 700kHz GBW
• 3x TI TL084 Quad OpAmp JFET 3MHz GBW Product Link
  
• 8x LM293 Comparator Dual
• 3x TL2843 Current Mode PWM Controller Product Link
  
• 3x HEF4066BT Quad SPST Analog Switch Product Link
  
• 4x SFH6156-3 Opto-Coupler Product Link
  
• 4x Avago HCPL-J312 2A Optio-Isolated Gate Drivers Product Link
  
• 3x IR4427 Dual Low-Side Driver Product Link
• Power
• 7x SMD Diode MUR120T3G 200V 2A Product Link
  
• 1x SMD Diode STTH212S 1200V 2A Product Link
  
• 3x TO247 Diode APT40DQ100 1000V 40A Product Link
  
• 2x TO247 Diode DSEI 30-60A 600V 30A Product Link
  
• 3x SMD MOSFET IRFBF20S 900V 1.7A Product Link
  
• 6x TO264 MOSFET (yes, MOSFET) APT28M120 1200V 28A Product Link
  
• 1x SMD IGBT SGB02N120 1200V 3A Product Link
  
• 2x TO247 IGBT IKW25T120 1200V 25A Product Link
  
• 2x TO247 IGBT SKW30N60 600V 30A Product Link
• Misc
• Clips for mounting the TOxxx power semiconductors to the heatsink standoffs. These weren't cheap either I'm sure.
• 2x Massive heatsinks - about 20cm x 50cm
• 6x EPCOS Varistor (625Vrms 6.5kApk) + Thermal fuse (3A 250V 102°C)
• Bunch of massive WAGO PCB Connectors
• Bunch of nice silicone cables with "solar" connectors
• Some wires with high quality crimp contacts (these faston crimps were probably 20-30 cent each in bulk).
• 4x Panasonic Relay SPST-NO 250V 20A (9V coil)
• 1x 16x2 character LCD module (no backlight).

[Mads Barnkob]

As I commented on youtube, SMA solar inverters are popular here around. The models that are now slowly being retired/failing (a.k.a. the stuff that shows up for cheap or free) are just full of salvageable parts. Unfortunately, more recent models seem to be less salvage-friendly; f.ex. one we got installed in our house has the heatsink integrated into the casing.

That is an impressive amount of good stuff in one unit.

I agree on the whole-cast being shite thing. I dug through a pile of maybe 20 solar inverters and only 5 of them even had TO-247 IGBTs, rest were multi phase bricks or press-fit skiip modules. Heat sinks are cast as part of the chassis, with DC bus capacitors and inductors imbedded into it with epoxy. Its complete trash to the metal scrappers as its now a whole unit of electronics waste and they cant get the heat sink or inductors "out".

Legislation is properly so badly made that when manufacturers have to assure it will be recycled, its not necessarily recycled in a smart, re-useable or low energy cost way. It is just possible.

[TMaxElectronics]

I found it very helpful to just search ebay for the big IGBT manufacturer names from time to time. I found everything from skm200 bricks for 5€ to an entire 400A VFD output stage which included a 20kg heatsink, 12 electrolytic caps and 6 SKM300 halfbridges for 5€

Same thing goes for electrolytic capacitors, even the big ones can sometimes be found for als little as 2,50€.

Oh and regarding salvaged IGBTs from induction cookers: you can just use an induction cooker powerstage directly for a tesla coil. Thats how I got started building coils

[dru]

I pretty much only use salvaged components for my circuits, partly due to high cost of appropriately rated transistors but also because I think a lot about how many good components are being put into landfills and stuff. The best sources I've found are similar to what you listed, in general I look for devices that were designed to last a long time: Inverter microwaves, telecom power supplies, various induction heating devices (cooktops, furnaces/foundries), industrial SMPSs, arc inverter welders, high power audio amps, a treadmill, air conditioners. Anything that was designed for 24/7 operation, medical equipment, or power supplies for use in server farms etc. though those are hard to find. Any equipment used in environments where human safety was conditional on operation will have very robust components.

[Mads Barnkob]

A look at a bag of IGBTs and MOSFETs that I quickly salvaged from industrial electronics like induction cookers, solar inverters, welding machines, car and battery charges and other common high power electronics with switching inverters.