On my [SPAM] Bee, I use a Huanyang HY series Inverter and a 110V 1.5KW water cooled spindle. They've worked flawlessly for the time I've owned them, about 1-1/2 years. I cut at 16000rpm and yesterday and today during cutting the rpm started (seemingly) randomly dropping to about 15600 rpm. It doesn't seem to happen right away... it's after I've cut for a while, maybe an hour or so. The drop lasts for anywhere from maybe 3 to 10 seconds, then it comes back up to 16000 rpm. Yesterday it only did it twice but today it did it several times during a 15-minute cut. Any ideas on what could cause this & where to start? Thanks....
unplug and replug both ends of the pwm cable, after 18 months it is likely that the pins are corroding a little and creating some resistance, unplug slides them against reach other nd cleans them up.
My Blackbox (original) died - a sudden disconnect and a slight smell of burnt electronics. It's worked reliably for years, & it was just time to go. I replaced it with the new Blackbox X32. After configuration & upon first run I saw that my spindle speed was off so I adjusted the voltage on the Blackbox to make it correct. It dawned on me that this issue I posted about might be the Blackbox, not the VFD, and I can now confirm that it was and I no longer have this issue. Spindle speed is now stable. For some reason (probably a failing component?), the Blackbox must have been sending varying voltage to the VFD. Maybe this will help somebody with a similar issue.
