More Tinkering- Drillpress upgrade *w/pics*

[NZAPP1]

I agree with WoodGuy and Alan
I was the electrical supervisor for a large paper manufacture in their R&D department for 15 years working with servos, PLC'S and VFD drives. There is some special program and some time wiring that need to be done to insure safety of the equipment . I am also willing to help if needed

 

[Alan in Little Washington]

What Woodguys says.

Interesting facts on the "open, drip-proof" vs "TEFC" motor issue- The original Delta supplied motors taken off my old 46-700 lathe and my newer Delta 17-965 drill press during these mods (and the bandsaw motor I also replaced) were open-drip proof Emersons (lathe and bandsaw) and an unknown China motor (drill press.) The only TEFC motors came on my Unisaw (Baldor), DJ-20 jointer (Baldor), and new/old Delta 43-373 HD Shaper (Baldor.) I also replaced the shaper motor with a TEFC Leeson since the Baldor was 3 phase- the replacement motor (from Ebay) was cheaper than a 3 hp VFD. I have good dust collection and routinely blow the motors out. FYI, the ODP motor I put on the lathe, has an enclosure that looks a lot like a TEFC enclosure until you actually examine it.

Another fact about running many VFD's with single phase input is that you may have to derate the hp rating. Another reason to educate yourself before jumping in.

I would recommend against any open style motor like a drip proof. They don't handle a dusty environment of a shop well at all. I know Alan knows what he is doing so he will keep an eye on it, but you've gotta think about the environment.
Did you know that just because a motor is TEFC (Totally enclosed fan cooled) doesn't make it dust proof? There are additional seals that must be added to those motors to keep the dust from prematurely wearing out the bearings of the motor along with clogging the centrifugial switch if it is a single phase motor. There is a lot of knowledge that you must have before you make modifications on your own as Alan has also stressed. I would not do anything like this on your own without doing your research and knowing what you are stepping into. I'm willing to provide help to anyone as is Alan I'm sure, but in the end you need to bring yourself up to speed on what not to do and what you can do.

I have designed and built a number of large machines professionally and even when you think know what you are doing you'll find you didn't know it all. :eyeslam:Every drive (inverter) is different, every application is different.....

 

[woodguy1975]

Lots of guys forget to use their DC and blow out their motors on their Tablesaws leading to motor problems. Break out those air hoses boys!!!

I have a 3HP Leeson TEFC in my TS now that has all the rubber seals added, siliconed the peckerhead, and blow it out routinely, run DC always, and still have had problems with dust infiltration into the motor and bearing failure. Inverter duty motors have no fan on the back side to blow dust into the motor. A major plus when it comes to Tables. I hope I can make one fit if this Leeson goes.

John

What Woodguys says.

Interesting facts on the "open, drip-proof" vs "TEFC" motor issue- The original Delta supplied motors taken off my old 46-700 lathe and my newer Delta 17-965 drill press during these mods (and the bandsaw motor I also replaced) were open-drip proof Emersons (lathe and bandsaw) and an unknown China motor (drill press.) The only TEFC motors came on my Unisaw (Baldor), DJ-20 jointer (Baldor), and new/old Delta 43-373 HD Shaper (Baldor.) I also replaced the shaper motor with a TEFC Leeson since the Baldor was 3 phase- the replacement motor (from Ebay) was cheaper than a 3 hp VFD. I have good dust collection and routinely blow the motors out. FYI, the ODP motor I put on the lathe, has an enclosure that looks a lot like a TEFC enclosure until you actually examine it.

Another fact about running many VFD's with single phase input is that you may have to derate the hp rating. Another reason to educate yourself before jumping in.

 

[cpowell]

Great information.

I work with inverters a lot. We have hundreds of inverters ranging from 2HP to 100HP in use in our process.

Alan hit a key point in fitting the inverter to the application. Select a shieve ratio that will allow you to run in a range of 30 to 90 Hz at the motor if possible. I have found inverters do quite well on high inertia loads within this range. We NEVER use inverter rated motors in this speed range. All are TEFC. We DO use inverter class motors where they are required to run VERY slow (less than 10 Hz). Downtime due to inverter/motor failures is less than 1 percent. We have around 2500 motors in the plant.

My plant has a lot of airborne dust generated by the product we process. I have spent time looking at electrical distribution, controls, and automation/plant information systems in the U.S., Canada, Mexico, Brazil, Africa and Argentina and have actually seen more failures due to inverters overheating - NOT motor problems. Most of the time the biggest problem was selection of an inverter that did not have a dustproof enclosure.

Many inverters will give you a temperature readout that shows the temp inside the enclosure. When the temp starts to rise above normal, isolate power and blow down the inverter enclosure - especially the cooling fan. Our inverters and motors last many years in a bad environment.

Again, if using 220V single phase, the required input current will be about twice what is listed on the inverter for a 220V 3-phase input. Just use a larger inverter (twice as large).

Chuck