Thanks for all the thoughts and responses. I’m over it now, but yesterday’s tirade was mostly because all of my coworkers had bailed early and I was in this big cubicle farm all alone, other than the customer support person (for accounting and such, not technical). She had no idea that the stuff we work on doesn’t typically last that long, most often because the machinery it’s attached to doesn’t.
This was a 250HP drive on an ammonia refrigeration screw compressor. As I recall from the original project they wanted VFDs simply as glorified soft starters because the entire plant ran on generators (common in Alaska) and they needed to limit the starting current to the motor FLA, something that can only be done with a VFD. So it’s likely that these drives never saw any extreme duty in their lifetime.
His beef was centered around a claim that I told him it would last 50 years. Even 30 years ago I would not have been that stupid, so I told him he must have heard that from someone else when we were competing for the project and since I won, he ascribed it to me. He took added offense to my questioning his memory. Whatever... talk to the hand.
I talked to the guy who sold him the new drive and told him what he can look forward to. He pointed out that this bozo is in his mid seventies, so it’s highly unlikely he will be around the next time this drive fails. Although... it’s true that new drives are not likely to last that long.
The other thing that bugs me is that again, as I recall, this was one of 4 ammonia compressors on the original fish processing plant. I wonder if the others are still running or if he only brought this one down to California with him? I forgot about that until afterward, now I no longer care enough to call him back. Oh well. My conscience is clear, I know I would have never fed him a line of BS like VFDs lasting 50 years. I make a point of being clear on that issue: 7-10 years on average, with a few rare exceptions, but generally longer than the machines they are running anyway. Back in the 80s when I started specializing in VFDs, I don’t even think I would have said even that long, because at that point I had not seen one installed for that many years yet. Thinking back, I probably commissioned my first one in 1985 (a Saftronics drive in a Klockner Moeller MCC), so by 1988 I would not have seen more than 3 years of use.
