Looking forward to the new website...PowerPlasma DCV

[macdarren]

I'm looking forward to the new website....I was hoping it might show up today.

I am sure this info will be on the new site but for now can you post the cutting voltages of the various PowerPlasma models? 50/60/70/80

and also for comparison the 2 MOSFET units.

Knowing the amperage is all fine but overall power would be nice too.

I'm getting close to decision but I wanted to know some relative power numbers so I can make a better comparison between the units and with units I know.

Thanks

[performance]

According to the factory specs, both are rated at 200V OCV.

Now with that said, there is a cutting performance difference, based of how the arc is generated and controlled through the torch. The IGBT will cut more typically than a mosfet unit.

[macdarren]

Yeah, Open circuit voltage really doesn't tell you anything since you don't cut open circuit.

What I was looking for was actual cutting power output. Saying 50A is also not the real story either since it is power not Amps that seems to be the real measure. I am sorta amused that cutters tend to be rated in Amperage not Watts. That is like vacuum cleaners being rated in Peak HP instead of CFM and Lift....come to think about it vacuums are also often rated in Amps too but again that really only tells you how much power it consumes not what it does with that power which is all you really care about.

I was kinda hoping for some graphs like I have found for some other cutters..see pictures if I attached them correctly. Note this is a 6-8 Kilowatt 60 Amp cutter with an Open Circuit Voltage of 275V
Now it is probably less efficient at about 74% vs what I think is the 60A PP efficiency of 93% (Is that what you mean by power factor or do you really mean Power Factor) Even at 100% efficiency the 60A PP could be at most about 6.8 Kilowatts (31A * 220V) That is why I would like to see the sort of graphs I posted for the PowerPlasmas. I could just assume that a 6.8KW max unit is generally able to cut less or cut slower than the 8KW unit that draws 11KW of power (49A) but having a graph of cut speeds might show that better design and efficiency pay off over massive power consumption and output power. I know I am sorta picking at things and crunching numbers is far from a true measure of a product but I read regularly about this cutter being better than some other even when they have similar Amp numbers (just like you mentioned about the PP and its MOSFET brother) and after digging up some graphs and numbers on several units I am starting to think I see a pattern...where quoting big Amp numbers is for marketing not for real life cut quality....not saying anyone does this to mislead since clearly the market has settled on Amps as being the measure I just find it curious that people don't mention DCV or KiloWatts except what you can extrapolate from various other spec numbers.

[performance]

MacDarren,

Yes, you are picking at the details.


But on the PP50 the arc voltage is 100V at 50 amps, 88V @20 amps. Start amps is 39 A with 31 operating. You do the math....lol.

The SuperCut, I don't have right now, but I am sure someone can cite it for you off their machine.

[macdarren]

well I'll do the math since it is pretty easy in this case.....

50A * 100V means the PP is a 5 Kilowatt unit at max, 1.7 KW at 20A.

If the wall voltage is 220V and the operating current is 31A then it draws 6.8 KW making almost exactly the same efficency as the unit I posted the graphs for 73-74 percent efficent (5KW Out / 6.8KW in)

This is of course ignoring the whole RMS power thing on the AC side but I think using the same easier math when comparing one cutter to another then things are fair if not perfectly accurate.

[dwdw]

Would the output be calculated at 1.2 times the RMS since it is a modified DC output. Is the current averaged since it is a pulsed output PWM frequency on time verses off time.
just my 2 cents.
dwdw

[macdarren]

It is really hard to know if the manufacturer doesn't spec the output power since I have now idea about the output wave form...that is why I have started looking at input power. I know there can be efficiency differences between the units due to how the power supplies are made but I think efficiency is probably similar when using similar type of supplies (ie hi-freq switched) and most everyone specs the input current....I note the most difference there between the big name american brands and the bigger name foreign units.