In my last entry to the Oliver restoration blog I wrote that the VFD I bought was faulty and it had to be sent back to the supplier to evaluation. I received a replacement about a week ago and have set out to get power to the saw.
For those not familiar with VFD’s it is a Variable Frequency Drive. It works by varying the frequency of the electricity. In the USA our electrical system is set at 60 Hertz, the VFD is able to change that to just about what ever you want, within the limits of the drive itself. By changing the hertz on the drive it will vary the speed of the motor, so one of the nice benefits of the VFD is that you get a variable speed motor. In my case the variable speed is not necessary on the table saw. However, it would be really nice in the case of a lathe.
The past few days I have spent mounting the drive in an enclosure designed for the VFD. It is metal and sized for adequate air flow for cooling. It is mounted on the wall approximately 8 feet from the saw.
The VFD I chose is capable of running a 3hp motor with 10.5A, cost was $165. The drive is very easy to install, it requires 230VAC single phase input and output is 230VAC 3 phase. It is a very cost effective way to reap the benefits of a 3 phase motor.
I installed a separate 230V 20A circuit just below it and ran the wires into the box. All you have to do is simply plug it in. The rest of the wiring is a low voltage, 24VDC, control system to a remote switch which was mounted on the saw and the 3 leads for the motor itself.
The switch is an old Westinghouse momentary contact that I think fits really nicely with the age and art deco features of the saw. The 3 leads coming from the top of the switch will be placed in conduit and run into the hole just below the switch for power to the motor, a ground will also be added. These older saws did not have provisions for a ground so it needs to be added at some point for safety.
When I did my first VFD installation, which was on a 3ph unisaw, I was a little reluctant to tackle the job myself. If you have ever wired a motor you know that power goes to the switch AND the motor in the same junction box. Not the case with the VFD. The motor and switch controls are separate and never come into contact with one another. The remote switch is mounted where ever you want it and wire it in. Then a few parameters are changed within the drive to recognize the switch. The switch controls the VFD telling it to turn the motor on. Its really slick. Plus the control system is 24VDC there is NO chance of ever being shocked.
Now that I have power all that is left is a little touch up painting, put the top back on, mount the fence and possibly build a mobile base. I am hoping to have it all wrapped up within the next week. Thanks for following along with my little saw and I can’t wait for the next restoration.
Which should I restore next? A mid 1920’s Crescent 8” jointer or a newly acquired Delta 10” bandsaw from the early 30’s? By the way, the bandsaw is pre-Delta as we know it. Delta Specialty, not Delta Manufacturing.
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