Hi Bob,
VFD¡¯s would work¡ but a few questions. What size motors, I¡¯m assuming you already have three phase, are you wanting to continue to use three phase or convert to single phase input using the VFD to convert to three phase? Do you also have a separate scoring motor or is it belt driven, if you even have scoring?
Two VFD¡¯s would eliminate a lot of issues in the stock Felder electrical system. You could wire one motor to each VFD, use the e-stop and start string for both VFD¡¯s and that would eliminate the whole selector switch portion of the machine. You do of course double the cost of the VFD¡¯s and depending upon the size of the motors, that may or may not be much of an issue.
Nice thing about two would be that you could set a pretty aggressive stop time on the saw, and the shaper as well if you used a braking resistor on the one for the shaper. The internal braking on most vfd¡¯s wouldn¡¯t be adequate to stop heavy shaper tooling in less than 5-10 seconds.
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On Jun 18, 2022, at 10:13 AM, Robert Johnson <
woodewe@...> wrote:
When my vintage 2004 KF500 S did not apply braking to the saw blade, I contacted Felder for help.? In a series of e-mails with Timothy Kennedy at Felder Group USA, I received the bad news that the repair is expensive.? My electrical system is obsolete, and no parts are available.? To restore braking, a new main populated circuit board is required and that requires a technician come and rewire my machine.? The total labor and travel estimated cost alone was $4,374.94.
?
The saw is useable and like most table saws,let the blade coast to a stop.? Although the braking feature is highly desirable, the cost of repair is too much.? The support from Timothy at Felder was quick and detailed, but had no alternative to up dating my machine.? He also sent me the schematic for my machine.? I was curious to see if a pair for VFD¡¯s could be integrated into the saw.? Other than preserving the requirement that all the microswitches are closed, perhaps the VFDs could take over motor control.? Remoting their control pads to the overhear saw guard/dust collector would give soft start and braking.? And for the shaper give forward or reverse rotation and variable speed.? The variable speed could eliminate belt changing if the torque is adequate for the job, and spindle could be run at better RPM¡¯s for router bits.
Most likely I¡¯ll live without braking but must wonder how difficult it would be to run the saw and shaper with VFD¡¯s.? Anyone have the same experience with older machines and what do you think of using VFD¡¯s?
Bob Johnson
Whidbey Island, WA
