Paul C. Buff, Inc. Technical Forum

I wish I had remembered more of my electronics training from 23 years ago, so that I would understand why that light bulb helps :)

The light bulb is a high tech (like a brick) current limiting device. No matter how much current your flash unit really wants to draw from your inverter, the bulb is in the way, and determines the speed limit. You just cannot force more than 60 watts of power through the series wired 60W bulb. It's just like driving behind Granny on a one lane Autobahn. You might have the desire to go faster, but.....

Voyager

Does it also smoothens out the Modified Sine wave to a true sine wave?

Thanks. That makes perfect sense now.

So, since we are on the subject, do these super quiet Honda generators (like a EU1000i or similar) that use inverters qualify as a pure sine wave inverter?

Yes, the "i" series can be used with our lights. You will want about 1000 watts per light to prevent the generator from sensing the surge and ramping up power once the lights fire. In doing so, the generator can cause damage to the lights.

TS

No, it really doesn't help in that department. There are filtering schemes that can smooth out the "noise" inherent in stair-step approximations of a true sine wave, but when using devices that are sensitive to that kind of noise from an inverter, it is easier (and likely cheaper) to just go for an inverter with a clean sine wave output to begin with. The only real benefit of using a series load like a light bulb is that it can limit maximum surge current to a value that an inverter with borderline capacity might tolerate. You also reduce voltage available to your lights, but the PCB units seem to have a generous input voltage operating range.

The best solution is to go for the right inverter from the start. I have several new 22Ah batteries here at home, so I'll be buying Vagabond II inverters and bags for my lighting. That saves the bulk of shipping costs as a bonus, but the key unit is that well designed Vagabond inverter system. It seems like a bargain compared to other options....

Voyager

Good to know. I just ordered the EU2000i model, mainly for home power backup, but will double nicely at a portable strobe power supply, when needed. The good thing is that you can buy two of these, and put them in parallel for double the capacity...