Hi All
Just joined the forum after my friend started this thread on my behalf.
The Invertor was purchased from ebay (last year) and was sold as a 2.2 KW VAT20 GE U20N 2K25. It looks identical to a Teco MiniCom E2-203-HF 2.2KW which direct drives sell (but much cheaper. I have in the past purchased a Teco Invertor from Direct drives and apart from the name I cannot find any difference, even the manual instructions and settings are the same.
I have carefully wired up the invertor, and have (amongst other setting changes) changed the F12 carrier frenquency settings across the whole range. F1,2,3,4, and 6 make the motor whistle,additionally in these settings and the other settings, the motor has a slight rumble and vibration which can be felt throughout the lathe. Also the turned finish both with tipped tools and sharp hss is poor.The Lathe is a 1977 Colchester Student, and the motor is a 3hp AEI Kapax. In desperation I have changed the bearings (waist of time), windings all measured the same and were like new. This is the second invertor fitted to this lathe the previous one also made the motor whistle but it was much worse and was only useable in the highest Carrier Frequency setting. The vibration is evident with the drive belt disconnected. Increasing the HZ up to approx. 75 is where the motor is happiest. Any Ideas?