Telemecanique ATV16U41M2 motor VFD - Page 1
Forum section: electronics / repair

author: shakalnokturn
author_rank: Super Contributor
timestamp: February 20, 2023, 01:22:29 pm
content: I'm trying to repair an oldish Telemecanique (now Schneider electric) FVD.It's a single phase 230V input, 3 phase 230V 2.2kW output model with braking, it was in use on a pottery wheel.I haven't had access to the full machine only the VFD unit.When first received the optional 7 segment display was erratic and throwing random fault codes.Checked internal SMPS voltages and found them to be too high with +5V being around 7.5VI reflowed the whole SMPS section and replaced a couple of electrolytics on the control (CPU) daughter board, after this the PS voltages made more sense, display behaved normally.Testing without load the display would return a "drF" (Drive failure) fault code as soon as the input control voltage was turned up enough for the drive output to become active.Further testing and doing a little reverse engineering I found a shorted 2N7002 between CPU board and IPM brake control input.The error was triggered by the IPM fault output line. In this design the low side IPM controls share a supply referenced to power bus negative, the high sides each have their own floating 15V supplies. Only the low side fault output is sent to the CPU, the high side fault outputs are unused.The IPM was checked with my Hameg scope's component tester, all phases showing identical curves, no shorted IGBT's.Scoping the 6 CPU board IPM control outputs (Un, Vn, Wn, Up, Vp, Wp) didn't show anything suspicious, I then scoped the voltage across the current shunts along with the fault out line. This showed that there was a significant current peak that triggered the IPM's over-current detection as soon as the drive became active.For further troubleshooting I cut the positive 300V input line to the IPM and inserted a 2kW 20 Ohm resistor with a parallel light bulb. This allowed me to scope the unloaded power outputs without triggering the "drF" fault. Nothing suspicious on the waveforms, there was something abnormal though: The light bulb would flash once briefly just before the control voltage was low enough to stop the drive. Unfortunately it wasn't possible to capture the output on the oscilloscope when this happened.I was also able to run an (unloaded) motor for some time (still with the series resistor), after a few minutes current draw shot-up: IPM's "Up" IGBT had shorted.I don't see what I may have done wrong (no doubt someone will tell me soon...) so for now I'm sticking with the idea that when the SMPS was running too high it exceeded the IPM's internal gate driver's maximum voltage damaging it. In certain conditions the switching must have allowed for shoot-trough.Anyway now I need a replacement IPM, it's a Mitsubishi PM30RSF060. I can't see any reputable sources selling them at reasonable prices, they can be found on Aliexpress or eBay for about 20€ though, my main fear is wasting money on a fake.Funnily many of the photos on these stores have an "Original" image covering the "Mitsubishi" name on the IPM photos, that gives me even less confidence...Anyone out here with experience replacing Mitsubishi IPM's who would like to recommend a reliable seller?

author: timeandfrequency
author_rank: Frequent Contributor
timestamp: February 20, 2023, 01:53:02 pm
content: Hi shakalnokturn,You may have a look to UTSsource who wants 25 bucks for the PM30RSF060 part.https://www.utsource.net/sch/PM30RSF060.html

author: shakalnokturn
author_rank: Super Contributor
timestamp: February 20, 2023, 02:08:58 pm
content: Thanks. I've run into fakes buying from UTSource on eBay in the past.Although they look more serious than the average far east seller I'm not convinced they'll give me more satisfaction for the little extra cost.Do you have any experience with their IPM products?

author: timeandfrequency
author_rank: Frequent Contributor
timestamp: February 20, 2023, 03:05:45 pm
content: Quote from: shakalnokturn on February 20, 2023, 02:08:58 pmUnfortunately no.