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(Meta: HN wouldn't let me write "120 kW.")

I have no idea if this marketing wank or not, but it seems plausible and investigable with some due-diligence.

I think it's a pulsed laser, but I can't find a good sentence to quote in the website. https://en.wikipedia.org/wiki/Pulsed_laser

They are "off" most of the time accumulating energy, and then they send a very high power pulse, so the average power is not so high. The on-off switch is many times per second.

In some applications it is more important the maximal power than the average power.

[About the title: It's probably a false positive in the automatic filter to prevent spam and linkbait, sometimes it's too strict. You can use the "edit" link below the title to fix it. If that fails, you can send an email to the mods hn@ycombinator.com so they fix it. Anyway, it would be a good idea to send the mail so they fix the automatic filter.]

They are "off" most of the time accumulating energy, and then they send a very high power pulse, so the average power is not so high.

They are talking kilowatts, not joules, so the average power is very high. To get that sort of average power, any pulses must either be quite long or extremely powerful.

The datasheet claimed 100% duty cycle CW depending entirely on chilled water capacity. I think the military weaponized one are pulsed in the same average energy range, but have a much higher impulse that causes destruction of targets. So the commercial CW ones can cut a steel plate at a certain rate, but the military pulsed ones would obliterate a target.
No, it was a CW 100% duty cycle if enough cooling water were available. I questioned the claims. The intended applications are large-scale manufacturing and fabrication, not thermally-damaging an ICBM in boost phase (awww :[ ).
Note that they're talking watts not joules. That implies continuous output, or heavy duty-cycle output.

At 480V, that's 250 Amps. That's a very heavy-duty current, and necessitates very heavy conductors to reduce the resistance as much as possible.

Wouldn't it be better to use a higher voltage and allow for the use of a lower current, and not so massive conductors?

There are many models and I'm not an expert so I'm not sure which type they are using. But note that the usual number of kilowatts is for the power during the peak. For example from: https://en.wikipedia.org/wiki/Q-switching#Typical_performanc...

> Typical performance

> A typical Q-switched laser (e.g. a Nd:YAG laser) with a resonator length of e.g. 10 cm can produce light pulses of several tens of nanoseconds duration. Even when the average power is well below 1 W, the peak power can be many kilowatts. Large-scale laser systems can produce Q-switched pulses with energies of many joules and peak powers in the gigawatt region. On the other hand, passively Q-switched microchip lasers (with very short resonators) have generated pulses with durations far below one nanosecond and pulse repetition rates from hundreds of hertz to several megahertz (MHz).

Yep. And it's continuous wave (CW) and 100% duty cycle, if you have a fairly sizable water chilling plant to support it. I don't believe it straight out, but would need to do manufacturing-side due-diligence and see demos (like cutting AR500) to believe it.