Hi
I built particals accelerator, for the ion source im using tungsten wire 0.5 mm 3cm long , the power supply i used smps 5v 30 amps.
The device worked for 5 minutes and then it said im resigning. I think the short protection issue. Are there any way to bypass the protection or make another power supply that can handle the filament? Without short ?

 

What's the design current for the filament and some detail about the device in general? Is the power supply shutting down (resigning) due to overloads or what? Usually you need to slowly burn-in a new filament to degas it and to allow the uniform heating of the solid metallic lattice to reduce cracking, warping and hot-spots before it heats to operational temperature.

https://www.thermofisher.com/blog/materials/electron-source-fundamentals/

 

I'm not clear on what failed. If the supply shut down or dropped the output voltage because of excessive thermal stress you can be sure that a more catastrophic failure would have ensued had those measures been bypassed. I would suggest that you consider a more capable supply with better load distribution and better heat sinking if you intend to continue the operation.

Alternatively running the filament from an AC source might allow you to achieve your goal without the need for expensive semiconductors running at such power levels. Trust me the filament does not care. A 220v to 6.3V filament transformer should do the job nicely.

 

Hi
Thanks for the reply. Yes i tried toroidal transformer and i removed the secondary winding and rewind it with 4 meter 6 gauge. The voltage what i got 1v, 29 amps AC . It worked but, i don't feel the filement temperature is hot enough like 5v 30 DC.
Of course the dc gave 150 Watts. And the AC 29 watt. But the more i wind the transformer the more amps im getting.
Regarding the accelerator, 50kv ac with drift tubes.

 

What's the design current for the filament and some detail about the device in general? Is the power supply shutting down (resigning) due to overloads or what? Usually you need to slowly burn-in a new filament to degas it and to allow the uniform heating of the solid metallic lattice to reduce cracking, warping and hot-spots before it heats to operational temperature.

https://www.thermofisher.com/blog/materials/electron-source-fundamentals/

Different designs i tried. The power supply works but when i connect it to the filament it stops working . The power supply is smps type i can't control the power.

 

For 220 to 6.3V the voltage ratio is 35:1 Using 850 ma from the line should give you about 29.68 Amperes out. That should be just about right

 

For 220 to 6.3V the voltage ratio is 35:1 Using 850 ma from the line should give you about 29.75 Amperes out. That should be just about right

I didn't get it .

 

The filament doesn't care AC/DC but the particle beam does.

Hi
Thanks for the reply. Yes i tried toroidal transformer and i removed the secondary winding and rewind it with 4 meter 6 gauge. The voltage what i got 1v, 29 amps AC . It worked but, i don't feel the filement temperature is hot enough like 5v 30 DC.
Of course the dc gave 150 Watts. And the AC 29 watt. But the more i wind the transformer the more amps im getting.
Regarding the accelerator, 50kv ac with drift tubes.

Nice! Vacuum shouldn't be a problem with that turbo pump on the chamber.

It looks to me you're running the filament with too much power. Looking at the video I see the glow past normal thermal emission temps, it seems to be in the heavy vapor shuttering range, moving metal ions instead of just electrons.

 

The filament doesn't care AC/DC but the particle beam does.

Nice! Vacuum shouldn't be a problem with that turbo pump on the chamber.

It looks to me you're running the filament with too much power. Looking at the video I see the glow past normal thermal emission temps, it seems to be in the heavy vapor shuttering range, moving metal ions instead of just electrons.

Im using hydrogen gas (protons). Im accelerating protons . The tungsten is for electron bombardment the hydrogen atoms .to get the H ions

 

Im using hydrogen gas (protons)

So, it's a ion beam source. That's my line of work. You still need to be able to control filament power manually or with a control system related to arc current of the feed gas plasma.
What type of ION source are you using?
https://cds.cern.ch/record/1693319/files/p9.pdf

 

So, it's a ion beam source. That's my line of work. You still need to be able to control filament power manually or with a control system related to arc current of the feed gas plasma.
What type of ION source are you using?
https://cds.cern.ch/record/1693319/files/p9.pdf

Yes its ion beam source. The plasma type
Done. going to get a power supply with adjustable voltage and amps. I have one but afraid that it will blow up. And they are not cheap.
Thanks for the help

 

I didn't get it .

It is the basic operation of a transformer. When you step down the voltage you step up the current by the same ratio.
\( 220 \text{ VAC}\;\times\;0.85\text { Amperes}\;=\;187 \text{ watts} \)
\( 6.3\text{ VAC}\;\times\;29.68\text {Amperes}\;=\;187\text{ watts} \)
That is for an ideal transformer. You can expect that there will be some losses.

 

The filament doesn't care AC/DC but the particle beam does.

Nice! Vacuum shouldn't be a problem with that turbo pump on the chamber.

It looks to me you're running the filament with too much power. Looking at the video I see the glow past normal thermal emission temps, it seems to be in the heavy vapor shuttering range, moving metal ions instead of just electrons.

Does it also care about the current and voltage ripple on the SMPS output under heavy load where it might also slip into DCM?

 

Does it also care about the current and voltage ripple on the SMPS output under heavy load where it might also slip into DCM?

The usual spec for industrial Ion source DC filament supplies is usually around 100 millivolts of ripple at the full rated power.
https://www.ntecusa.com/docs/1672D_data (2).pdf

This picture is for a several KW ion beam source that does this sort of damage on internal parts.

 

Yes its ion beam source. The plasma type
Done. going to get a power supply with adjustable voltage and amps. I have one but afraid that it will blow up. And they are not cheap.
Thanks for the help

Set a current limit on the power supply for the safe (determined from experience) plasma arc current for the desired beam extraction current.

 

The usual spec for industrial Ion source DC filament supplies is usually around 100 millivolts of ripple at the full rated power.
https://www.ntecusa.com/docs/1672D_data (2).pdf

This is for several KW ion beam sources that do this sort of damage on internal parts.

View attachment 276452

There was a noticeable lack of information in the original post by the TS. I stand corrected.

 

There was a noticeable lack of information in the original post by the TS. I stand corrected.

No correction needed when you have to tease required information from the TS.