If you're in the market for a dust collector, your first stop should be Bill Pentz's Cyclone Dust Collector Research site.
The Felder RL125 is bulky for a small basement shop, but it had a few advantages that convinced us to choose it. It fits under the low ceiling in the shop; some popular cyclone-style dust collectors were too tall. It's relatively quiet as these things go. It filters dust so effectively that for our uses we don't need an exhaust duct to the outside. It has a long-life filter with an easy-to-use built-in filter cleaner. And it's convenient to empty the dust bin when it's full.
When we ordered our RL125, Felder didn't offer a single-phase version. This presented a bit of a problem, since we don't have three-phase service or any other three-phase gear in the shop. Based on discussions in the Felder Owners Group we chose a Teco-Westinghouse FM100 variable-frequency drive rated for 7.5HP to handle the conversion from single-phase to three-phase. (The RL125 motor is 5HP, but the VFD needs the additional capacity to cope with single-phase input.) Dealers Electric had a good price and filled the order very quickly.
The FM100 gave us the ability to run the RL125 at its European standard frequency of 50Hz, which makes for a noticeable reduction in noise. It also provides overcurrent and thermal protection. Inverter wonks can find our FM100 parameters here. (We take inverters seriously in this household.)
Finally, there was the question of how to turn on the dust collector when one of the woodworking machines was in use. There are automatic systems for doing this (EcoGate makes a good one), but for now we decided to avoid the extra complexity and expense. Allen built a CK1616 kit remote control (alternate source here) and connected it to the FM100's run/stop terminals. The remote works perfectly, but if we had to do it over again, we'd look for a different solution. The reason is that the FM100 fan runs even when there's no load to drive, so turning off the dust collector doesn't eliminate that background noise. We're still looking for a better solution, but the current setup works well enough that it's a low priority.
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