There are a few options for commercially available RFC. American rotary seems to use open drip Baldor motors and Phoenix uses TEFC. I have a few belt grinders and both have Baldor TEFC motors which makes sense for the proximity to grinding dust. My Quincy compressor has an open drip Baldor motor. I’m not likely to be grinding near this RFC but since there are options I’d like to hear your opinions. What would you want in your shop? Thanks
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Open drip vs TEFC on rotary phase converter
- Thread starter PT Doc
- Start date
- Replies 11
- Views 2,116
thermite
Diamond
- Joined
- Sep 21, 2011
I would LIKE "TENV". But they are large and heavy and more expensive motors.
I HAVE a bought-brand-new "ODP".
All it needs is a clean place to do its s**t. A few extra feet of wire makes that possible, and I don't have as much annoying noise - however mild - in the work zone into the bargain.
If an equation that simple is so challenging as to need outside advice as to a "decision"?
Putting the 3-P power off the RPC to actual USE may prove far the greater ball-buster for yah, then. Best to grow a pair in advance.
motion guru
Diamond
- Joined
- Dec 8, 2003
- Location
- Yacolt, WA
TENV much preferred, typically bumped up a frame size or two from TEFC, and more inertia so less likely to sag when starting a load . . . not to mention quieter without the annoying fan whirring away under the end bell.
thermite
Diamond
- Joined
- Sep 21, 2011
Mine is. Wasps, hornets, and such as well.
Cheap metal mesh wastebasket from Office Depot at each end - no external load to couple a shaft to, after all.
Even with wastebasket cost, the idler is still lighter and cheaper than either a TENV or TEFC.
thermite
Diamond
- Joined
- Sep 21, 2011
Not much cheap about it. But.....Given what I have OTHERWISE had to spend to connect a nominal 10 KW (at 8,000 ft AMSL), actual 12 KW, peak 15 KW "tactically quiet" NATO-spec MEP-803a Diesel gen set?
The cost for the RPC and P-P distribution was more in (recycled) Square-D switchgear, 3-P lock-out-able rotary disconnects, a good grade of twist-lock outlets and heavy SO cordsets by far than in the basic distribution wire, load center to RPC, or RPC to 3-P mini-panel.
Mind - tight space, small shop of but approx 1200 SF and less than 2:1 aspect ratio - nearly square IOW - means relatively short WIRE runs here, but just as many boxes, protective devices, disconnects, cordsets, and connectors as a larger space, similar "consumer machine" count.
"Page Two" will see the RPC exiled to a back-yard shed location alongside the Diesel, so I'll be reliant on indicator lamps to even know it is whirring. Gen set is 3-P capable, BTW, so part of the wire and conduit run can be "borrowed" when mains power is available and gen set is offline.
The Phase-Perfects need friendlier year-round temps than an RPC. Those will stay indoors, just migrate into an adjacent space to better isolate them from the chip and dust making area than at present.
One other thing... "eventually", I - or my Widow/Estate - will need to sell this house.
"We craftsman" seldom think of it, but for the general real-estate market, "shop equipped" is a negative to more potential buyers than it is a positive.
Accordingly, all of this is being done with surface-mount duct or conduit and SO cordsets in a manner with a specific eye towrd ease of removal. IOW. NONE of it neatly buried in-wall as the normal residential electrical services are - not even the 230 VAC 1-P outlets.
The RPC is even meant to migrate from hand-truck/ furniture-dolly portable to its own permanent wheeled mount.
May or may not do the P-P the same way. They don't NEED that, but wuddn' yah know it? Daggone gravity seems to get stronger as I grow older! Go figure.
Most things in a space this small benefit from permanent skates or such that let me sort of "garage" a machine not in current use or frequent use. The shaper, pantoengraver, smaller mill and drillpress, for example.
2CW, Your space and environment, mileage may vary.
PS: I said "Office Depot" expanded mesh wastebasket. One end is actually a re-purposed rectangular hanging file-folder box. These are wire framed, expanded metal goods that DENT if looked at crosswise, so showed up at closeout prices.
I can sort a dent way faster than I can fab such goods from scratch, so grabbed 'em cheaply when I could. A bit of copmmon galvanized sheet steel does the rest.
Fotos oafter I deal with a failing over-age-in-grade and badly wind-damaged roof over the whole shebang...
jim rozen
Diamond
- Joined
- Feb 26, 2004
- Location
- peekskill, NY
ODP works fine for me, has for 30 years or so. Rodent problem is apparently kept at bay with feline
bioweapons. Mice just don't come in the house anymore.
bioweapons. Mice just don't come in the house anymore.
Not much cheap about it. But.....Given what I have OTHERWISE had to spend to connect a nominal 10 KW (at 8,000 ft AMSL), actual 12 KW, peak 15 KW "tactically quiet" NATO-spec MEP-803a Diesel gen set?
The cost for the RPC and P-P distribution was more in (recycled) Square-D switchgear, 3-P lock-out-able rotary disconnects, a good grade of twist-lock outlets and heavy SO cordsets by far than in the basic distribution wire, load center to RPC, or RPC to 3-P mini-panel.
Mind - tight space, small shop of but approx 1200 SF and less than 2:1 aspect ratio - nearly square IOW - means relatively short WIRE runs here, but just as many boxes, protective devices, disconnects, cordsets, and connectors as a larger space, similar "consumer machine" count.
"Page Two" will see the RPC exiled to a back-yard shed location alongside the Diesel, so I'll be reliant on indicator lamps to even know it is whirring. Gen set is 3-P capable, BTW, so part of the wire and conduit run can be "borrowed" when mains power is available and gen set is offline.
The Phase-Perfects need friendlier year-round temps than an RPC. Those will stay indoors, just migrate into an adjacent space to better isolate them from the chip and dust making area than at present.
One other thing... "eventually", I - or my Widow/Estate - will need to sell this house.
"We craftsman" seldom think of it, but for the general real-estate market, "shop equipped" is a negative to more potential buyers than it is a positive.
Accordingly, all of this is being done with surface-mount duct or conduit and SO cordsets in a manner with a specific eye towrd ease of removal. IOW. NONE of it neatly buried in-wall as the normal residential electrical services are - not even the 230 VAC 1-P outlets.
The RPC is even meant to migrate from hand-truck/ furniture-dolly portable to its own permanent wheeled mount.
May or may not do the P-P the same way. They don't NEED that, but wuddn' yah know it? Daggone gravity seems to get stronger as I grow older! Go figure.
Most things in a space this small benefit from permanent skates or such that let me sort of "garage" a machine not in current use or frequent use. The shaper, pantoengraver, smaller mill and drillpress, for example.
2CW, Your space and environment, mileage may vary.
PS: I said "Office Depot" expanded mesh wastebasket. One end is actually a re-purposed rectangular hanging file-folder box. These are wire framed, expanded metal goods that DENT if looked at crosswise, so showed up at closeout prices.
I can sort a dent way faster than I can fab such goods from scratch, so grabbed 'em cheaply when I could. A bit of copmmon galvanized sheet steel does the rest.
Fotos oafter I deal with a failing over-age-in-grade and badly wind-damaged roof over the whole shebang...
I too like the idea of having most everything on casters for ease of moving and storage. Thinking about what will happen with a home shop has crossed my mind. Hopefully I’ll be in good health when I want to begin passing everything onto someone younger. Until then I’ll keep adding to it and enjoying life.
rons
Diamond
- Joined
- Mar 5, 2009
- Location
- California, USA
Suppose a RPC is using a idler motor and the balancing act with capacitors is very good when under load. Now turn off the load. A lighter Baldor open-drip motor will vibrate and make more noise than a heavier GE open-drip motor. If a commercial RPC is used then the balance capacitors are selected for some middle off the range load or maybe some maximum load. I've tried TEFC as well and got quieter results, but not that much. So I use what is on hand. Especially since the last time I compared a Weg and a Baldor in the same class. The Weg was in the mid $500 range and the Baldor was in the mid $900 range.
jim rozen
Diamond
- Joined
- Feb 26, 2004
- Location
- peekskill, NY
Money matters.
Free beats retail every time. I *would* have used a TEFC if that had been free. But the ODP
one, was free.
Free beats retail every time. I *would* have used a TEFC if that had been free. But the ODP
one, was free.
thermite
Diamond
- Joined
- Sep 21, 2011
Casters.. and even my beloved Northern Tool machinery (cheap)skates.. have been falling out of favour, here at Chaos Manor. Got tired of cutting grass in me dotage as the fool stuff keeps growing back, and put down about fifty tons of various gravels.
Looking greedily at basic El Cheapo hand trucks, and even a HF "welding" dolly with bigger wheels.
Easier to make the combo detachable for future-proofing and other uses if/as/when.
Also not a lot more spend than a set of GOOD casters, comparable all-up weight rating as a cheap hand truck.
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