Thanks Jazz, you're right, I meant the generic, it is as you say an PLCM E3 from Purelogic, a Russian company. I'm using the Zapp ZP5A-INT breakout board, I'm not planning to try and control the spindle speed using that but I do have a USB dongle that supports RS485 that I've read will work for speed control. We'll see, right now as you say I've got to explore the VFD manully and get that going, with perhaps a little less noise.