Paul C. Buff, Inc. Technical Forum

I just came back from a location sesson where I was unable to use my (old but very reliable) Ultra 1200's. When turned on they would begin to act erractically. The flash tubes would flash without any input from a slave or camera connection. I turned them off because I feared damage to the units. Could this have been caused by faulty wiring? The building, is less than 20 years old.

Probably not. Was there any thing plugged into the RJ11 remote connector when this happened?

No. I didn't even have slaves attached yet. Just the power cord and a 25 ft. extension cord were attached to the units. When I returned, I tested them in our camera room and they worked perfectly. I use these units on location often and with extension cords, always, and have not had that experience before.

Did you also use the extension cord when you tested in your camera room? A poor ground could cause rapid firing. This can come from the local outlet, or can come from an aging extension cord. Or, could come from an aging power cord.

I re-tested all of my power cords and extension cords and could not reproduce the problem.

It is likely an issue in the AC power supply at the location you were in.

I have come to that conclusion, too. However I bought a circuit tester to check the area and all recepticles came up ok. I'll just have to be aware of the potential for problems in that area and use a vagabon there. Thanks for the help.

You know, this is a really good post - I had this problem too at a specific location and was trying to figure out for the life of me why the heck my AB800s and AB1600 were just firing without reason and I hadn't thought about the power fluctuation/unstability of the power supply! Now it makes sense because I do NOT have that problem in other locations - thanks for posting this!!!

Chuck

WOW! To further confirm the validity of this problem (unreliable power source) and solution (moving to another power outlet), I had another experience this weekend! Just sharing so folks will see that it isn't the flash units but the power supply...

Interestingly enough, I am learning that you can apparently have some variation in power outputs to different power outlets in the same room! I got the uncontrollably flashing strobes problem in one outlet, moved it to another outlet on the other side of the room and didn't have the problem at all - not one random triggering event!

Moral of the story: If your flash units are triggering randomly, unplug the power and move to another outlet and give that a try!

Thank you so much for bringing this subject up. I started experiencing this yesterday with one unit, then it went away and today with a different unit and it didn't go away. I was confused as heck because it was working all yesterday then today the flash tube would just flicker or fire away at random times. I started to believe it might have been the age of the units which is pretty old. I changed the flashtubes and cleaned the remote contacts, but it continued to fire without warning. I was ready to send it in for warranty work until I decided to try the tech forum. Thankfully you had asked the question and that there was an answer!

I just tried the unit on a totally different outlet and it worked like a charm! Thanks so much. It saved me a lot of lost time and money for shipping the unit only to have the techs tell me nothing was wrong.

By the way, I registered on this forum just so I could write this. I'm so thankful!

8/20/14 Update: One of the lights would still fire periodically when there was sunlight coming into the room. I got some blue tape (gaffers would have worked) and covered the white slave dome on the back of the strobe and that fixed that.