Author Topic: Is a 60UF 800VDC Dawncap good for an induction heater?  (Read 796 times)

Offline yourboi

  • High Voltage Enthusiast
  • *
  • Posts: 32
  • Karma: +1/-0
    • View Profile
Is a 60UF 800VDC Dawncap good for an induction heater?
« on: June 09, 2024, 03:31:30 PM »
thank you to all for reading this post. Should I go for one of the 60UF 800VDC variants or is the capacitance too high and voltage too low? Also Is it worth it to buy a premade snubber circuit or should I build my own? Circuit will be a half bridge or full bridge everything's in the purchasing stage. thank you guys for reading my post.

I will likely buy a 0.44UF 6KV for tesla coiling in the future as I am already paying for shipping.

Extra: If anyone has spare IGBT'S or capacitors I will gladly buy them off you If I get a deal I am from the USA.

Offline Anders Mikkelsen

  • Global Moderator
  • High Voltage Experimenter
  • *****
  • Posts: 77
  • Karma: +9/-0
    • View Profile
Re: Is a 60UF 800VDC Dawncap good for an induction heater?
« Reply #1 on: June 09, 2024, 05:44:29 PM »
Too low ripple current rating and too high capacitance for practical use. Practically you want 10 µF or less, at hundreds of amps, for practical induction heating.

I would look at something like these: https://www.ebay.com/itm/266845269192

Offline yourboi

  • High Voltage Enthusiast
  • *
  • Posts: 32
  • Karma: +1/-0
    • View Profile
Re: Is a 60UF 800VDC Dawncap good for an induction heater?
« Reply #2 on: June 20, 2024, 01:37:41 AM »
I ended up purchasing these from the seller. How did you find such a good deal? I can't find any similar deals on large induction heater capacitor. I actually can't find many at all.

I've been searching for used IGBTs for months with no luck. However, recently, after I bought that capacitor, I was looking around and found many mislabeled eBay listings for used IGBT modules some priced around $7 each. So, I bought a few.

I purchased 3 SKM200GB125D 1200v 160 @80c Igbt modules as I saw a video of the youtuber Jmartis 2 running an impressive 80khz tesla coil off of the skm100gb125dn and comparing the specs to the skm200gb125d they seemed very similar in switching speeds since I am making an induction heater which I plan to keep around 20khz-40khz I assumed they were capable of the task. I also found the datasheet mentioned soft switching at a maximum of 100khz for soft switching induction heating applications which gave me the go ahead to purchase 3 of them for $30 which I think is a deal.

Their specs are as follows:

1200V

Collector current: 200A @ 25°C

Collector current: 160A @ 80°C

td(on): 75 ns (turn-on delay time)

tr: 36 ns (rise time)

td(off): 420 ns (turn-off delay time)

tf: 25 ns (fall time)

I believe they are a good selection for my price range and in general. I plan to use a phase locked loop so I am looking at soft switching speeds.  I also purchased a SKM200GB12F4.

I was also looking at the CM300DY-13T which is a 650V 300A Igbt but much slower. I am wondering if it would be useful In a soft switching application as it was also at quite a cheap price. Its specs are as follows.

td(on): 400 ns (turn-on delay time)

tr: 200 ns (rise time)

td(off): 400 ns (turn-off delay time)

tf: 400 ns (fall time)


Offline Anders Mikkelsen

  • Global Moderator
  • High Voltage Experimenter
  • *****
  • Posts: 77
  • Karma: +9/-0
    • View Profile
Re: Is a 60UF 800VDC Dawncap good for an induction heater?
« Reply #3 on: June 20, 2024, 04:02:38 PM »
Good call, these caps will serve you well. I've been using eBay for almost 20 years and have some saved searches, so I do come across deals regularly. The trick as you discovered is to find listings that are not listed under the most obvious name.

All of those IGBTs should be fine for induction heating at 20 - 40 kHz, with preference to the 125D and 12F4 due to their speed. Losses in IGBTs during soft switching are not easy to calculate from datasheet numbers, so you just have to try and see what works best, but it's less critical at these frequencies.

How are you planning to do the power control? Are you going for a transformer coupled series resonant tank?

Offline yourboi

  • High Voltage Enthusiast
  • *
  • Posts: 32
  • Karma: +1/-0
    • View Profile
Re: Is a 60UF 800VDC Dawncap good for an induction heater?
« Reply #4 on: June 21, 2024, 11:34:45 PM »
I’ve never heard of a series resonant tank induction heater. I was under the impression that induction heaters were always parallel lc circuits. I have seen a video of a dual resonant Tesla coil being used as an induction heater with a metal can as a dummy load. I thought that that was only possible from the short pulse width of the Tesla coil interrupter limiting the current. I attached a picture of my schematic. It still is just a rough schematic. From my testing a large heatsink on the gate drive ic massively increases the current capabilities and short circuit survivability of the 27425. Usually it overheats very fast in CW and burns up. Not only does adding a large heatsink allow it to run CW but also allows it to survive short circuits on the inverter bridge itself when they happen. Since adding a heatsink my Tesla coils have never had to deal with a failed gate driver even with the igbt’s fail short and the driving circuitry is left running for a few minutes while troubleshooting the issue.  Back to the point I am not to familiar why most induction heater designs use a coupling transformer besides mains isolation. I could imagine if using a series LC circuit I may need a coupling transformer. Is it a critical component to include in my circuit?



I wrote this post earlier and wrote a lot about the missing components in the schematic then recently updated my schematic so its kind of a jumbled mess. I'm still posting it anyways how it is.

Offline davekni

  • Executive Board Member
  • *******
  • Posts: 2859
  • Karma: +134/-2
  • Physicist, engineer (electronic), and hobbiest
    • View Profile
Re: Is a 60UF 800VDC Dawncap good for an induction heater?
« Reply #5 on: June 22, 2024, 03:11:12 AM »
Looks like you are using LTSpice for drawing schematics.  Great start towards simulation.  Simulation will allow exploring topologies and seeing issues with some.

To start, simulate just the work coil and resonant parts (L4, cap above L4, C3, and C4).  Drive this network with a pulsed voltage source, simplest replacement for M1/M2 half-bridge.

Have fun learning!  Experimenting with simulation is much faster and less expensive than experimenting with actual electronics.  Then build something that works in simulation.
David Knierim

Offline Anders Mikkelsen

  • Global Moderator
  • High Voltage Experimenter
  • *****
  • Posts: 77
  • Karma: +9/-0
    • View Profile
Re: Is a 60UF 800VDC Dawncap good for an induction heater?
« Reply #6 on: June 23, 2024, 08:14:17 PM »
You can't use a voltage source inverter with a parallel resonant tank circuit. The inverter provides a square wave voltage rich in harmonics, while the parallel tank presents a very low impedance to all the harmonics, drawing large current peaks at each switching event. Another way to view it is that the switching devices would need to charge and discharge the tank cap to the full bus voltage on every switching cycle, incurring tens of kilowatts of losses.

You have a few options

You can make the tank series resonant, in this case it will present a low impedance at the fundamental frequency and a high impedance to the harmonics, which is what you want. Since the tank presents a very low impedance to the inverter, sqrt(L/C)/Q (typically 10 - 100 mohm), you need an impedance matching transformer to drive it with high voltage IGBTs. This would typically be in the range of 5:1 to 25:1, often with a single turn secondary.

Especially for low impedance tank circuits (Lwork less than 500 nH or so), LCLR can be a good option. This uses an inductor between the bridge and parallel tank circuit to make it appear like a series resonant tank to the inverter. This is my preferred option, as it allows the main work coil current to only circulate between the cap and coil without needing a transformer in line. This makes for more compact workheads and allows very low inductance work coils. Unlike the series resonant tank, LCLR matching will not present unity power factor to the bridge across a wide range of tank Q factors, so the inverter will have to deliver more reactive current (and higher turn-off current) if you plan to work with a wide range of loads. This topology is better suited for use with SiC MOSFETs than IGBTs, but can be made to work well with either.

The last practical option is to do a current source (or actually inductance-source) inverter to allow direct drive of a parallel resonant tank. This is essentially like the classic "ZVS/Mazzilli" driver (which is in reality a Baxandall oscillator), but it needs some extra refinements in order to work well at high power. Blocking diodes in series with your switches, some conduction overlap (analogous to dead time in a voltage source inverter), and a bit of phase lead (switching the devices before the tank voltage zero crossing) does wonders.

The last option is to not use a resonant tank, which is still better than driving a parallel resonant tank with a voltage source inverter. In this case, your switching devices will need to provide the entire reactive current of the tank, which is usually between 5 and 100 times the real power. This factor is the tank circuit Q factor, and it's determined by how well your load is matched to the coil size, the conductance and magnetic permeability. For a steel pipe inside a closely fitting coil, this can be as low as 3, but if trying to heat copper or aluminium then you're looking at more like 50 - 100. So if you want to process 10 kW for example, you need 500 - 1000 kVAR circulating in your tank circuit. If you have a 1 ohm tank (=sqrt(L/C), this would be between 700 A 700 V and 1000 A 1000 V.

High Voltage Forum

Re: Is a 60UF 800VDC Dawncap good for an induction heater?
« Reply #6 on: June 23, 2024, 08:14:17 PM »

 


* Recent Topics and Posts

post Re: Problem with SSTC
[Solid State Tesla Coils (SSTC)]
Nunu00
July 12, 2024, 10:17:36 PM
post Making a HV prove
[Electronic Circuits]
Alberto
July 12, 2024, 09:01:08 PM
post Re: Problem with SSTC
[Solid State Tesla Coils (SSTC)]
davekni
July 12, 2024, 01:33:37 AM
post Re: Problem with SSTC
[Solid State Tesla Coils (SSTC)]
Nunu00
July 12, 2024, 12:17:32 AM
post Re: Restoring a Rogowski coil calibrator
[Capacitor Banks]
davekni
July 11, 2024, 07:38:26 PM
post Re: Restoring a Rogowski coil calibrator
[Capacitor Banks]
klugesmith
July 11, 2024, 06:30:00 PM
post LOD No Double Resonant SSTC?
[Solid State Tesla Coils (SSTC)]
ColinHeath
July 11, 2024, 06:08:30 PM
post Re: FIRST DRSSTC SKM400GB128D OCD SETTING
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Admiral Aaron Ravensdale
July 11, 2024, 12:24:56 PM
post Re: Strange QCW Streamer Behavior
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
July 11, 2024, 06:42:23 AM
post Re: Syntherrupter Lightsaber Sender Programming
[Computers, Microcontrollers, Programmable Logic, Interfaces and Displays]
Cameron Prince
July 11, 2024, 05:46:07 AM
post Syntherrupter Lightsaber Sender Programming
[Computers, Microcontrollers, Programmable Logic, Interfaces and Displays]
Cameron Prince
July 11, 2024, 05:26:51 AM
post Re: Strange QCW Streamer Behavior
[Dual Resonant Solid State Tesla coils (DRSSTC)]
ZakW
July 11, 2024, 02:50:54 AM
post Strange QCW Streamer Behavior
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Coupling
July 11, 2024, 12:59:55 AM
post Re: Help for people buying the "12-48 Volt 1800/2500 Watt ZVS induction Heater"
[Electronic Circuits]
petespaco
July 10, 2024, 07:10:34 PM
post Re: Understanding and tracking upper and lower poles of QCW DRSSTC
[Dual Resonant Solid State Tesla coils (DRSSTC)]
flyingperson23
July 10, 2024, 06:52:42 PM
post Re: Understanding and tracking upper and lower poles of QCW DRSSTC
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Anders Mikkelsen
July 10, 2024, 06:28:19 PM
post Re: FIRST DRSSTC SKM400GB128D OCD SETTING
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Alex_1996
July 10, 2024, 01:34:09 PM
post Re: Silicon(e) plasma
[General Chat]
alan sailer
July 10, 2024, 12:09:06 AM
post Re: Problem with SSTC
[Solid State Tesla Coils (SSTC)]
Nunu00
July 09, 2024, 11:52:00 PM
post Understanding and tracking upper and lower poles of QCW DRSSTC
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Simranjit
July 09, 2024, 07:37:22 PM
post Re: Silicon(e) plasma
[General Chat]
MechatEng2023
July 09, 2024, 07:30:05 PM
post Re: UD2.7C outputs very odd single square wave pulses
[Dual Resonant Solid State Tesla coils (DRSSTC)]
flyingperson23
July 09, 2024, 03:30:49 AM
post Re: UD2.7C outputs very odd single square wave pulses
[Dual Resonant Solid State Tesla coils (DRSSTC)]
verliebt_in_neukölln17
July 09, 2024, 12:51:02 AM
post Re: UD2.7C outputs very odd single square wave pulses
[Dual Resonant Solid State Tesla coils (DRSSTC)]
flyingperson23
July 08, 2024, 11:30:44 PM
post Re: Why so cheap?
[General Chat]
alan sailer
July 08, 2024, 10:57:10 PM
post UD2.7C outputs very odd single square wave pulses
[Dual Resonant Solid State Tesla coils (DRSSTC)]
verliebt_in_neukölln17
July 08, 2024, 10:21:01 PM
post Why so cheap?
[General Chat]
MRMILSTAR
July 08, 2024, 09:55:24 PM
post Re: Syntherrupter - A Feature-rich, Polyphonic Interrupter
[Computers, Microcontrollers, Programmable Logic, Interfaces and Displays]
Cameron Prince
July 08, 2024, 09:18:21 PM
post Re: Syntherrupter - A Feature-rich, Polyphonic Interrupter
[Computers, Microcontrollers, Programmable Logic, Interfaces and Displays]
Max
July 08, 2024, 05:17:49 PM
post Re: Syntherrupter - A Feature-rich, Polyphonic Interrupter
[Computers, Microcontrollers, Programmable Logic, Interfaces and Displays]
Cameron Prince
July 08, 2024, 04:49:20 PM
post Re: Tesla coil in FEMM
[Beginners]
Simranjit
July 08, 2024, 04:28:43 AM
post Re: Tesla coil in FEMM
[Beginners]
davekni
July 08, 2024, 04:06:53 AM
post Tesla coil in FEMM
[Beginners]
Simranjit
July 08, 2024, 03:46:49 AM
post Re: Best core material for QCW Buck modulator ?
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Simranjit
July 08, 2024, 02:42:00 AM
post Re: QCWDRSSTC - Project Build
[Dual Resonant Solid State Tesla coils (DRSSTC)]
ZakW
July 08, 2024, 01:37:55 AM
post Re: First DRSSTC Build- Issues with Fibernet project
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Sebigamer
July 08, 2024, 12:53:08 AM
post Re: QCWDRSSTC - Project Build
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Anders Mikkelsen
July 08, 2024, 12:49:48 AM
post Re: Silicon(e) plasma
[General Chat]
alan sailer
July 07, 2024, 11:15:35 PM
post Silicon(e) plasma
[General Chat]
MechatEng2023
July 07, 2024, 11:04:43 PM
post Re: QCWDRSSTC - Project Build
[Dual Resonant Solid State Tesla coils (DRSSTC)]
ZakW
July 07, 2024, 09:39:07 PM
post Re: First DRSSTC Build- Issues with Fibernet project
[Dual Resonant Solid State Tesla coils (DRSSTC)]
flyingperson23
July 07, 2024, 05:32:56 PM
post Re: QCWDRSSTC - Project Build
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Anders Mikkelsen
July 07, 2024, 02:52:19 PM
post Re: No change in Phase Lead
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Anders Mikkelsen
July 07, 2024, 02:50:04 PM
post Re: Best core material for QCW Buck modulator ?
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Anders Mikkelsen
July 07, 2024, 02:20:11 PM
post Teardown of a APC SmartUPS VT 40 kVA
[Electronic Circuits]
Mads Barnkob
July 07, 2024, 10:02:22 AM
post First DRSSTC Build- Issues with Fibernet project
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Sebigamer
July 07, 2024, 09:23:58 AM
post Re: QCWDRSSTC - Project Build
[Dual Resonant Solid State Tesla coils (DRSSTC)]
ZakW
July 07, 2024, 12:44:53 AM
post Re: FEMM tesla coil simulation
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Simranjit
July 07, 2024, 12:08:50 AM
post Re: FEMM tesla coil simulation
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
July 06, 2024, 10:35:49 PM
post FEMM tesla coil simulation
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Simranjit
July 06, 2024, 09:42:43 PM
post Re: No change in Phase Lead
[Dual Resonant Solid State Tesla coils (DRSSTC)]
flyingperson23
July 06, 2024, 06:06:23 PM
post Re: No change in Phase Lead
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Admiral Aaron Ravensdale
July 06, 2024, 10:21:16 AM
post Re: No change in Phase Lead
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Admiral Aaron Ravensdale
July 06, 2024, 10:15:42 AM
post Re: QCWDRSSTC - Project Build
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Simranjit
July 06, 2024, 04:53:56 AM
post Re: No change in Phase Lead
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
July 06, 2024, 04:42:16 AM
post Re: QCWDRSSTC - Project Build
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
July 06, 2024, 04:09:50 AM
post Re: Best core material for QCW Buck modulator ?
[Dual Resonant Solid State Tesla coils (DRSSTC)]
flyingperson23
July 06, 2024, 03:07:11 AM
post Re: No change in Phase Lead
[Dual Resonant Solid State Tesla coils (DRSSTC)]
flyingperson23
July 06, 2024, 03:05:18 AM
post Re: QCWDRSSTC - Project Build
[Dual Resonant Solid State Tesla coils (DRSSTC)]
ZakW
July 06, 2024, 02:37:16 AM
post Re: QCWDRSSTC - Project Build
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Simranjit
July 06, 2024, 02:20:14 AM
post QCWDRSSTC - Project Build
[Dual Resonant Solid State Tesla coils (DRSSTC)]
ZakW
July 06, 2024, 01:55:14 AM
post Re: No change in Phase Lead
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
July 05, 2024, 11:50:37 PM
post Best core material for QCW Buck modulator ?
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Simranjit
July 05, 2024, 10:07:04 PM
post 230v Tesla coil and krypton gas
[Spark Gap Tesla Coils (SGTC)]
gravitysrainbow
July 05, 2024, 07:13:25 PM
post Re: No change in Phase Lead
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Admiral Aaron Ravensdale
July 05, 2024, 06:17:13 PM
post Re: Phase lead inductors
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Benjamin Lockhart
July 04, 2024, 11:40:45 PM
post Re: Sling Psychrometer
[Laboratories, Equipment and Tools]
Twospoons
July 04, 2024, 11:02:32 PM
post Phase lead inductors
[Dual Resonant Solid State Tesla coils (DRSSTC)]
flyingperson23
July 04, 2024, 06:28:08 PM
post Re: Sling Psychrometer
[Laboratories, Equipment and Tools]
klugesmith
July 04, 2024, 12:31:40 AM
post Re: FIRST DRSSTC SKM400GB128D OCD SETTING
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Alex_1996
July 04, 2024, 12:07:21 AM
post Re: FIRST DRSSTC SKM400GB128D OCD SETTING
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Alex_1996
July 04, 2024, 12:06:17 AM
post Re: FIRST DRSSTC SKM400GB128D OCD SETTING
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Benjamin Lockhart
July 03, 2024, 10:51:23 PM
post Re: FIRST DRSSTC SKM400GB128D OCD SETTING
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Mads Barnkob
July 03, 2024, 09:44:14 PM
post Re: Coax cable for DRSSTC interrupter?
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Admiral Aaron Ravensdale
July 03, 2024, 08:48:13 PM
post Re: Coax cable for DRSSTC interrupter?
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Simranjit
July 03, 2024, 08:24:50 PM
post Re: FIRST DRSSTC SKM400GB128D OCD SETTING
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Alex_1996
July 03, 2024, 08:12:55 PM
post Re: Coax cable for DRSSTC interrupter?
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Admiral Aaron Ravensdale
July 03, 2024, 07:29:53 PM
post Re: FIRST DRSSTC SKM400GB128D OCD SETTING
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Admiral Aaron Ravensdale
July 03, 2024, 07:21:38 PM
post Re: FIRST DRSSTC SKM400GB128D OCD SETTING
[Dual Resonant Solid State Tesla coils (DRSSTC)]
flyingperson23
July 03, 2024, 05:05:39 PM
post Re: FIRST DRSSTC SKM400GB128D OCD SETTING
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Alex_1996
July 03, 2024, 04:29:53 PM
post Re: FIRST DRSSTC SKM400GB128D OCD SETTING
[Dual Resonant Solid State Tesla coils (DRSSTC)]
flyingperson23
July 03, 2024, 04:09:11 PM
post FIRST DRSSTC SKM400GB128D OCD SETTING
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Alex_1996
July 03, 2024, 02:47:18 PM
post Re: Eliminating discharges from a SSTC
[Solid State Tesla Coils (SSTC)]
Alex_1996
July 03, 2024, 01:35:24 PM
post Re: Coax cable for DRSSTC interrupter?
[Dual Resonant Solid State Tesla coils (DRSSTC)]
flyingperson23
July 03, 2024, 02:19:03 AM
post Re: Coax cable for DRSSTC interrupter?
[Dual Resonant Solid State Tesla coils (DRSSTC)]
verliebt_in_neukölln17
July 03, 2024, 01:19:50 AM
post Coax cable for DRSSTC interrupter?
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Simranjit
July 02, 2024, 11:29:18 PM
post Re: Is this a good pulse experiment capacitor?
[Capacitor Banks]
Mads Barnkob
July 02, 2024, 09:59:07 PM
post Re: LabCoatz Staccato QCW No straight sparks
[Dual Resonant Solid State Tesla coils (DRSSTC)]
ZakW
July 02, 2024, 09:55:53 PM
post Re: Capacitor wiring for single phase 240 to split phase (180 degree) 240v
[Capacitor Banks]
klugesmith
July 02, 2024, 09:44:55 PM
post Re: LabCoatz Staccato QCW No straight sparks
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Admiral Aaron Ravensdale
July 02, 2024, 07:51:37 PM
post Re: LabCoatz Staccato QCW No straight sparks
[Dual Resonant Solid State Tesla coils (DRSSTC)]
ZakW
July 02, 2024, 06:14:07 PM
post Is this a good pulse experiment capacitor?
[Capacitor Banks]
FPS
July 02, 2024, 06:02:38 PM
post Re: LabCoatz Staccato QCW No straight sparks
[Dual Resonant Solid State Tesla coils (DRSSTC)]
Admiral Aaron Ravensdale
July 02, 2024, 11:37:46 AM
post Re: Building my first DRSSTC
[Dual Resonant Solid State Tesla coils (DRSSTC)]
davekni
July 02, 2024, 05:22:10 AM
post Re: Coulometric hourmeters
[Laboratories, Equipment and Tools]
davekni
July 02, 2024, 05:16:30 AM
post Re: Building my first DRSSTC
[Dual Resonant Solid State Tesla coils (DRSSTC)]
drobotk
July 01, 2024, 11:50:12 PM
post Re: Restoring a Rogowski coil calibrator
[Capacitor Banks]
klugesmith
July 01, 2024, 08:48:53 PM
post Uses for Weston's Little Bee probe
[Laboratories, Equipment and Tools]
klugesmith
July 01, 2024, 08:40:59 AM
post Re: Coulometric hourmeters
[Laboratories, Equipment and Tools]
klugesmith
July 01, 2024, 08:09:42 AM
post Re: Coulometric hourmeters
[Laboratories, Equipment and Tools]
davekni
June 30, 2024, 06:49:45 AM

Sitemap 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 
SimplePortal 2.3.6 © 2008-2014, SimplePortal