OK, here is what I have found so far. The search for the SMV Inverter started in Poland, then Germany, and finally the US. The model pictured seems to be obsolete -- or at least the case style is not the same as current models. The manufacturer is Lenze/AC Tech -- apparently Lenze, a German company, acquired AC Tech a few years ago. It appears that the particular model is part of the Lenze IP65 line of sensorless vector inverters -- probably one of the models designed for 240 VAC single phase input and three phase output.
If you go to the US web site, you have to register to be able to download any information, but you can go to the German web site and get the same stuff without registering. Here is the link to the operating manual in PDF format:
Lenze/AC Tech SMV Inverter Manual.
The one big drawback of the version shown in the ad and also all of the SMV Inverters shown in the web site is that there is no potentiometer speed controller on the panel of the inverter. However, there was a press release dated mid January that their SMV line of inverters will now include this feature on future production runs of SMV inverters. They are probably just now getting into the supply pipeline. Without the potentiometer for adjusting the speed, it means that you would need to go to the keypad and enter the speed change numerically which means that you would not be able to smoothly ramp the speed up or down with a knob. To me that would be a bit of a PITA. I am sure that it has provisions for you to add a potentiometer, but then there is the problem of where to mount it, etc.
The controller seems to be a bare-bones sensorless vector inverter, but that is probably adequate for your needs. There are a number of plug-in modules available for various additional functions which are probably over priced.
You can check with Friesen to get more technical details beyond their skimpy description. If I were you, I would be interested in finding out if the inverter is a model currently in production or if it is industrial surplus of an obsolete model and also whether it is new with warranty or used equipment. To me, the total package price seems to be way too high, but it has been a while since I have purchased any controllers and motors. Before it was "discovered and ruined" by the general public, I used to buy surplus industrial equipment on eBay for pennies on the dollar. I once bought a $2500 motor for $25. The shipping was a killer since the motor weighed about 100 lbs.
I did not have much luck tracing the origin of the motor. I looked at Hyosung industries in Korea and GEC Alstom motors in either India or South Africa, but ran into dead ends. My guess is that the motor is industrial surplus, either new or used, but no warranty for sure unless the dealer provides a warranty. The biggest drawback on the motor is the C-face mount which means more stuff that you need to buy to convert it to a foot mount.I would not weld anything directly to the motor housing because it would have two potential damaging effects:
- Almost certainly, it would affect the Glyptal insulation between laminations of the field magnet core.
- Very likely it could damage the Formvar insulation of the copper wire in the field windings.
You might want to search some of my previous posts in other threads concerning modify lathes with a variable speed drive. Basically, here are a few things to consider:
- I do not know the size of your current motor, but you really need a motor rated at about twice the HP when going to variable speed drive. This is because maximum available output power falls off with decreasing speed as opposed to a constant speed motor driving a load through a speed reduction set of pulleys where available power does not decrease.
- Power is important -- not torque. Torque matters if you are looking at gearbox loads, but not for work being done. Not that it is important, but there is very little difference between DC motors and AC induction motors when it comes to low speed torque.
- Motors do not like to run at low speed because they get hot from high current through the windings and insufficient cooling from built-in fans. This means that you should invest some effort in selecting the pulley sizes for optimal performance. The goal is to keep the motor running between about 70% and 120% of base speed for most commonly used speeds. This helps to keep the power output reasonably high and also helps the motor maintain adequate cooling. This is also why it is necessary to have two or three speed ranges depending on what you want for the lowest and top speeds from the lathe.
My overall assessment is that this controller would work, but it sems like a large sum to spend for somewhat limited benefit. However, this is a hobby and not a business so there is no "bottom line" justification necessary -- within reason, of course. Installation will require a bit more than just dropping it into place. Regarding portability, it would necessarily have to be a lathe that you design around this motor and controller since it would not be a drop-in replacement to any other lathe. My opinion is that the 1 HP motor is inadequate for use on a future system.
