I am at a makerspace where we currently have three CO2 lasers, a 150w BossHP3655, a generic 90-100w, and a generic 60w. They get a lot of community use.
Over the last two years, we have had four HV laser power supplies fry out on us, two of those in the last month. Three on the Boss, and one on the 90w. (Well we actually determined that the most recent power supply failure on the Boss was actually a failure of the insulation on the power cord attached to the supply, so we were able to cut the wire before the break and buy and install the fix. But it still seems related.) We are starting to suspect this might not be just crappy replacement parts, but perhaps our electrical system could be contributing to the problem. We are in a 100 year old building and run a lot of power hungry equipment in various departments, including kilns and a central dust collector.
A volunteer who knows somewhat more about electrical systems than I do did some basic testing with a multimeter, turning items on and off to see if we were getting any spikes in the voltage. We only got a variation of maybe a couple of volts when turning something on or off. The voltage was on the upper end of normal––around 121v––though the volunteer had tested the multimeter at his home workshop before helping me out, and it measured about the same there. Maybe the multimeter is not entirely accurate and runs a bit high?
Of course we could be getting some other types of infrequent power fluctuations perhaps caused by utility work. Or some spikes that are so quick that we can’t see them on the multimeter. We’ve also got some other testing we hope to do and are trying to get an actual licensed electrician in to look at our system.
Meanwhile, here are some specific questions that I would love to get some opinions on:
What is the typical upper safe voltage range for a 115v laser power supply? Would it be in danger of killing one at 125v? 130v? 150v? 220v?
Might a power conditioner have any downsides? Even if we’re barking up the wrong tree it might not be a bad idea to cover the possibility.
How fragile have others found these power supplies to be? Would we need to have something going seriously wrong to kill one?
I presume four dead power supplies on two machines in two years is well out of the ordinary.
Any chance a massive laser power supply failure could result in a broken tube? We have a seven month old tube that had a very nicely shaped beam (revealed by a sharp mode burn) and ran about 90w output. Just a couple weeks ago it dropped to about 65w and a still decent but not quite as sharp beam. By a week later, the mode burn test looked nothing like a gaussian distribution. Taking a smartphone video looking into the laser nozzle, I was able to see some sort of damage at the far end of the tube that does not seem to be visible from the outside. Could this be caused by its power supply frying?
Thanks for any help.
