Paul C. Buff, Inc. Technical Forum

How many bees can be plug in a typical 15A household circuit? 20A?

Can this be figured by b800, B1600, Einstein?

Thanks...John

There isn't a hard and fast answer as one doesn't usually know how many other things are using power on a given circuit. I shoot a lot of new model homes, and have noticed that when I plug 3 AB1600s into the same circuit, it occasionally trips. And maybe this has even happened with as few as 2 AB1600s plugged in. When I look at the breaker box, it invariably turns out to be a 15 amp circuit. I had previously thought that most codes required outlets to be 20 amps. When I have a problem, I just run an extension cord from somewhere else. I think I rarely get more than 3 lights on a given circuit as when I use more lights they are generally spread around so much that they will be on several circuits.

In about 5 years of extensively using AB1600s and more years using WL X3200s, X2400s and Ultras, I probably have only tripped breakers 20 times.

Three WL or AB of any power rating works fine. Should be the same with Einstein. Four are usable per outlet if you don't rapid fire for a long time. Only one Zeus per outlet because they cycle faster per WS and draw three times the recycle current.

But you have to consider any other equipment or lights, etc. that might be on the same breaker.

I was wondering about this very topic. In the spec for Einstein it says initial recycle surge current is 16A and tapers down to 5A. Is the initial surge so short that it won't trip a 15A breaker? What about with 2 or 3 lights? 48A surge?

I am not doubting what you're saying Paul . . . just curious, that's all.

. . . can't wait for those Einsteins!!! :roll:

Depending upon how intense the the initial current draw is relative to the circuit breaker rating (typical household breaker), and how long it lasts in time, initial surge currents can exceed the breaker rating by several times without causing the breaker to trip.

Because everything depends on the max load AND the time the breaker "sees" the max load, you will have to experiment with how many flash units you can link to any one real life circuit. It is likely that two or three units is a given (works for me), but you have to consider other full time loads like modeling lights, and any other resistive loads on that particular circuit as factors that can seriously reduce it's ability to handle multiple flash recharge demands at once.

On the bright side, most structures built within the past 30 years or so limit the number of outlets on any one breaker, and an extension cord or two will put you in contact with more power than my budget can even hope to overwhelm with flash units...

Voyager

In very new homes, the new code requirement for AFCI breakers might make this more of a problem. I haven't tested it, but AFCI breakers do show more of propensity for tripping with a sudden irregularity in draw (which is by design).

BTW, 14/15 amps is still the normal code requirement except for circuits in areas where heavy-draw appliances are expected (bathrooms, kitchens, for instance).

One other thing to keep in mind:

Shortly after buying my first WL1600 I had it plugged in to an outlet in the same room (and on the same circuit) as my PC. My computer is plugged into an APC battery backup/surge protecter, which is plugged into the wall.

I was messing around with the flash, testing its recharge speed, popping off a couple dozen pictures, when my battery backup started beeping and flashing warning lights. I'm not sure exactly what happened to it, but it was acting up for a couple of hours after I stopped shooting in that room; when I did a power cycle on it it would power back up and immediately start switching rapidly back and forth from the battery to the wall power, start beeping, shut off suddenly, etc. I let it chill for a while and after a few hours it was back to normal.

Just a word of caution, I suppose. I wouldn't pop off too many flashes if you have sensitive electronics plugged into the same circuit.

[edit] This was in a well-constructed apartment building that was built 5 years ago.

Household breakers can withstand the short term 60A from four AB/WL or the 45A surge from 1 Zeus pack. As for long term "fire when cycled", breakers are typically rated at 110% for one hour typically (16.5A for a 15A breaker). With four lights you could probably break one with maybe 10-15 minutes of continuously firing each time it recycled. But your lights would be mighty hot by then and would probably pop their own breakers first.

In short, we have essentially zero customer reports of blowing household breakers with three or four AB/WL . . . expect the same from Einstein.

Sounds like a flakey UPS.

I suppose that's possible but it has never given me any trouble before (or after). I'm fully aware that anecdotes != evidence, but the correlation between firing the strobe and the UPS freaking out is pretty strong in this case.

It doesn't seem like too big of a stretch to say that a very high current draw on a circuit could cause the surge protection on a separate device to kick in.