Chris Some good points about Inverters (Correctly termed Variable Frequency Drives) vs Converters. However, they are essentially meant to be "One Machine, One VFD" "You don't have to have tailored loads on an inverter" - read the Siemens installation and commissioning instructions for their 540 series ! "add some plugs or switches to change machines over and build a mobile control box to run it with" - sorry, I don't like the sound of that wrt Safety, EMC, manufacturers recommendations, IEE Wiring Regulations, etc, etc. Andy (Chartered Electrical Engineer keeping electricity live and safe) -----Original Message----- From: modeleng-bounce@xxxxxxxxxxxxx [mailto:modeleng-bounce@xxxxxxxxxxxxx] On Behalf Of Chris Crosskey Sent: 03 February 2006 18:28 To: modeleng@xxxxxxxxxxxxx Subject: [modeleng] FW: Question about phase converters Another attempt with rtf -----Original Message----- From: Chris Crosskey Sent: 03 February 2006 18:22 To: 'modeleng@xxxxxxxxxxxxx' Subject: RE: [modeleng] Question about phase converters Hi Steve, <Opinionated Rant> You've been told rubbish, solid state gives you infinite control over speed (within the limits of your motor to cope with it), all a rotary phase converter gives you is an expensive space consuming spinning transformer. For me I couldn't live without inverters, plus the fact that good ones can be had on ebay for peanuts while atavistic retards pay silly money for rotaries is just another plus in their favour </Opinionated Rant> I personally prefer inverters because of the speed control, you can individual ones on a per machine basis, as long as you aren't going over about 7.5kW (10HP) then an inverter will be a lot cheaper. Also you don't have to have tailored loads on an inverter, so if you're only using one machine at a time just by one big enough to cope with the biggest thing you use and add some plugs or switches to change machines over and build a mobile control box to run it with.... Chris Crosskey -----Original Message----- From: modeleng-bounce@xxxxxxxxxxxxx [mailto:modeleng-bounce@xxxxxxxxxxxxx] On Behalf Of Sehwuk@xxxxxxx Sent: 02 February 2006 19:52 To: modeleng@xxxxxxxxxxxxx Subject: [modeleng] Question about phase converters Chaps My first post and it's a question for any and all to answer :- Has anybody out there got, or used, phase converters ?. I'm just on the verge of building the new workshop for an attempt at a 41/2" Burrell but will need bigger machinery than I have at the moment, which really means going to 3 phase. I have heard good and bad things abut these bits of kit but would rather hear from people in the know (as it were). I have definately been told that a rotary will be better than a solid state. ALL replies, good or bad, will be most welcome. Steve Bodgers Retreat, Burwell MODEL ENGINEERING DISCUSSION LIST. To UNSUBSCRIBE from this list, send a blank email to, modeleng-request@xxxxxxxxxxxxx with the word "unsubscribe" in the subject line. ________________________________________________________________________ This e-mail, and any attachment, is confidential. If you have received it in error, do not use or disclose the information in any way, notify me immediately, and please delete it from your system. ________________________________________________________________________ MODEL ENGINEERING DISCUSSION LIST. To UNSUBSCRIBE from this list, send a blank email to, modeleng-request@xxxxxxxxxxxxx with the word "unsubscribe" in the subject line. MODEL ENGINEERING DISCUSSION LIST. To UNSUBSCRIBE from this list, send a blank email to, modeleng-request@xxxxxxxxxxxxx with the word "unsubscribe" in the subject line.