How to make a breakdown voltage tester for IGBT, Transistors,  Zener Diodes etc? - Page 1
Forum section: electronics / testgear

author: jdev99
author_rank: Regular Contributor
timestamp: July 20, 2023, 02:12:27 pm
content: I saw this tester on AliExpress and want to know if anybody made one themselves yet?The specs are:***********************************************************************"This portable voltage capability tester can help you to test MOSFETs, IGBT, diode, zener diodes, capacitors, Max. breakdown voltage capacity.It is easy to operate and test. The voltage and current adjust buttons allow you to adjust to the correct voltage and current to different tested objects.Features:1. The output voltage is direct current 110~2600V, you can turn the voltage adjust button clockwise to make the voltage bigger and counterclockwise to make the voltage smaller.2. The output current is 0.25~3.4mAh, you can turn the voltage adjust button clockwise to make the current bigger, and counterclockwise to make the current smaller.3. When testing MOS tubes, transistors, and Zener diodes, it is recommended to adjust the current to the minimum scale of 0.25mA. When testing the LED back light board, it is recommended to adjust the current to the maximum scale of 3.4mAh.4. Portable Size: The small size of this tool is very convenient for everyday use, you can carry it in your tool bag without taking up too much storage space.5. Built-in 660mAh large capacity lithium battery to supplys power, and you can recharge it through the Type-C interface in time.6. Wide Applications: This tool can be widely used for testing MOS, triode, IGBT, diode, zener diodes, diode bridges max. voltage capacity, capacitor and varistors' voltage verification, LED backlight and light board testing, etc.Specifications:Output voltage: direct current 110~2600VOutput current: 0.25~3.4mAhBattery: 1 * lithium battery, 660mAh (included)"*************************************************************Yes, I can just buy it, but it is much more fun to DIY it.https://www.aliexpress.com/i/1005004347430658.html

author: AVGresponding
author_rank: Super Contributor
timestamp: July 20, 2023, 04:02:32 pm
content: If that thing is genuinely capable of outputting 2.7kV as the controls suggest, I would question the clearances afforded by a Phoenix Contact connector. Also, it wouldn't need much output capacitance to be potentially lethal.

author: jdev99
author_rank: Regular Contributor
timestamp: July 20, 2023, 04:04:26 pm
content: I found some ideas here (in Russian):https://radiokot.ru/konkursCatDay2017/48/

author: Calambres
author_rank: Frequent Contributor
timestamp: July 20, 2023, 05:42:30 pm
content: Quote from: AVGresponding on July 20, 2023, 04:02:32 pmI've got one of those and yes, it can go up to 2.7KV and yes, it is quite dangerous indeed. On the other hand it works quite well for what's intended and I have not yet found a need to put it to its maximum voltage output other than to measure it.https://www.eevblog.com/forum/reviews/completely-non-sketchy-mini-high-voltage-transistor-tester-(emeco)/msg4826684/#msg4826684

author: T3sl4co1l
author_rank: Super Contributor
timestamp: July 20, 2023, 06:31:06 pm
content: That's basically what I do, with a HV supply of my own design.I use this power supply, with a calibrated output, and adjust its voltage slowly upwards until the DUT passes the desired test current.Test current is measured by the voltage drop across a 10k resistor. There is also a 100k resistor between HV and device to protect against unexpected avalanche, breakdown, and to limit capacitive discharge in case of intermittent contact. The total 110k resistance is calibrated (measured), and the voltage drop subtracted from the HV output to get the DUT voltage.This could all be automated and packed into an enclosure of course, but it doesn't really matter to me; there are few things I need to test in this way.(And if you do need to test things more often, it's probably that you need a megger instead.)Tim

author: Fungus
author_rank: Super Contributor
timestamp: July 20, 2023, 06:37:04 pm
content: What's the output current? Can I use it to charge enormous capacitors to 2.7kV?

author: Kim Christensen
author_rank: Super Contributor
timestamp: July 20, 2023, 06:38:38 pm
content: Quote from: Calambres on July 20, 2023, 05:42:30 pmCan it output 2.7KV @ 3.4mA? (9 watts of power) Or is the voltage lower at this current level?

author: thm_w
author_rank: Super Contributor
timestamp: July 20, 2023, 09:58:18 pm
content: If you are going to DIY it, come up with some extra feature. Maybe OLED graphical screen with higher current resolution, or auto-shutoff on arc, multiple outputs for gate signals, etc.Quote from: Kim Christensen on July 20, 2023, 06:38:38 pmNo, its lower, I measured 270V at 2.2mA so 0.6W. 2.7kV should be sub 0.5mA?Its still dangerous as you can charge a large cap to 2kV+.

author: Martin72
author_rank: Super Contributor
timestamp: July 20, 2023, 10:01:16 pm
content: At work we use a old isolationtester for this with an adjustable voltage up to 1000Vdc, but in 1V steps...