How to check this 400kV Boost Power Module's voltage and frequency?

Papabravo

Joined Feb 24, 2006
16,465
To measure the voltage you need a voltmeter with a high voltage probe. I don't think there is anyway to get inside for a frequency measurement.
I recommend you not try this at home with any kind of ad hoc solution - this thing can and will KILL you.
They don't make resistors big enough to make a viable voltage divider.
It is probably not suitable because the current will be extremely limited, as it is in all boost converters.
 
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DickCappels

Joined Aug 21, 2008
7,540
You might be able to find a suitable high voltage probe but it will cost hundreds of U.S. dollars or more.

Those things, as Papabravo said, dangerous! What possible use could you have for a voltage that high? (Not being rhetorical, that is a serious question.)
 

Thread Starter

LAOADAM

Joined Nov 21, 2018
628
To measure the voltage you need a voltmeter with a high voltage probe. I don't think there is anyway to get inside for a frequency measurement.
I recommend you not try this at home with any kind of ad hoc solution - this thing can and will KILL you.
They don't make resistors big enough to make a viable voltage divider.
It is probably not suitable because the current will be extremely limited, as it is in all boost converters.
Thanks.
I made a Resistance divider [RD] of: 1812K + 10k pot, and set Ratio: 20k.
Take the signal from 400KV measured 74V by a multimeter, and got nothing by the Oscilloscope, don't know why?
 

Thread Starter

LAOADAM

Joined Nov 21, 2018
628
You might be able to find a suitable high voltage probe but it will cost hundreds of U.S. dollars or more.

Those things, as Papabravo said, dangerous! What possible use could you have for a voltage that high? (Not being rhetorical, that is a serious question.)
Thanks.
My second asking is whether it can be used to start a TIG arc? that need 3000V about which I'm not handy, and use this instaed of for testing only.

BTW. I seem to smell the smell of oxygen during the experiment.
 
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Papabravo

Joined Feb 24, 2006
16,465
Thanks.
I made a Resistance divider [RD] of: 1812K + 10k pot, and set Ratio: 20k.
Take the signal from 400KV measured 74V by a multimeter, and got nothing by the Oscilloscope, don't know why?
How can you set the ratio of a 10K pot to 20K? Color me confused. 400kV will push almost a quarter of an ampere through that combo. You're lucky you didn't smoke something. I did tell you to be careful and you IGNORED me. I'm done!
 

DickCappels

Joined Aug 21, 2008
7,540
Here is something you should do: Look up how far 400KV can arc in air and how far it can creep over a PC board. They are long distances.

It probably cannot produce enough power to melt much metal, a MIG arc is probably not a possible application.

You smelled ozone caused by the high voltage in the air. If it were really 40KV you probably had corona at the ends of the wires, which would oxygen to combine into ozone.
 

Thread Starter

LAOADAM

Joined Nov 21, 2018
628
How can you set the ratio of a 10K pot to 20K? Color me confused. 400kV will push almost a quarter of an ampere through that combo. You're lucky you didn't smoke something. I did tell you to be careful and you IGNORED me. I'm done!
Thanks.
I guess I set the ratio=1812000/r= 20k, r=90.6 is not a professional approach, just roughly easy way confused you.
 

Thread Starter

LAOADAM

Joined Nov 21, 2018
628
Here is something you should do: Look up how far 400KV can arc in air and how far it can creep over a PC board. They are long distances.

It probably cannot produce enough power to melt much metal, a MIG arc is probably not a possible application.

You smelled ozone caused by the high voltage in the air. If it were really 40KV you probably had corona at the ends of the wires, which would oxygen to combine into ozone.
Thanks.
 

shortbus

Joined Sep 30, 2009
8,698
There is more to a high frequency Tig start than just high voltage. How are you going to apply it into the torch wire and not destroy the rest of the TIG welder circuit, if it doesn't already have HF start? At 40KV your using around 4 times the needed voltage.
 

Thread Starter

LAOADAM

Joined Nov 21, 2018
628
There is more to a high frequency Tig start than just high voltage. How are you going to apply it into the torch wire and not destroy the rest of the TIG welder circuit, if it doesn't already have HF start? At 40KV your using around 4 times the needed voltage.
Thanks.
I don't think it can be used as a arc start, but I did see some one mentioned use it fine some where.
It's easy to add a start if its a suitable V and F.
 

BobTPH

Joined Jun 5, 2013
3,482
Thanks.
No sound, it was said a DC.
Well then, the frequency must be zero, so why are you asking how to measure its frequency?

That thing works by converting the DC input to AC and running it through a transformer. Some such devices do make an audible noise. If you can’t hear it, the frequency is above your hearing range.

Bob
 
I have extensive experience with high voltage supplies.
This thing shown absolutely cannot produce 400 kV. Neither the wire insulation nor the air clearance are sufficient to support 40 kV, much less 400kV. Assuming it doesn’t flash over, the corona discharge on its own would consume all available power.

Having said this, to your question:
The resistive dividers used to measure those types of voltages are in the several gigaohm range. Consisting of several dozen of lower valued resistors spread out almost a meter in length. The terminals are spherical with at least 40 cm in diameter. The HV cable is coaxial with perhaps 4 or 5 centimeters of primary Teflon insulation.
 

Thread Starter

LAOADAM

Joined Nov 21, 2018
628
Well then, the frequency must be zero, so why are you asking how to measure its frequency?

That thing works by converting the DC input to AC and running it through a transformer. Some such devices do make an audible noise. If you can’t hear it, the frequency is above your hearing range.

Bob
Thanks.
I don't know that very well, I was learning it is a DC stuff. I got confused when I read some one's post.
 

Thread Starter

LAOADAM

Joined Nov 21, 2018
628
I have extensive experience with high voltage supplies.
This thing shown absolutely cannot produce 400 kV. Neither the wire insulation nor the air clearance are sufficient to support 40 kV, much less 400kV. Assuming it doesn’t flash over, the corona discharge on its own would consume all available power.

Having said this, to your question:
The resistive dividers used to measure those types of voltages are in the several gigaohm range. Consisting of several dozen of lower valued resistors spread out almost a meter in length. The terminals are spherical with at least 40 cm in diameter. The HV cable is coaxial with perhaps 4 or 5 centimeters of primary Teflon insulation.
Thanks.
 
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