VFD Cable Size

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1

Quick spindle question. I have the g-penny 1.5kW spindle with their cheapo VFD at 110V. I need to build the cable. It will be about 12-15 feet. (if it doesn’t matter for the size recommendation, I’ll leave it a bit long at 15 feed so I have enough for when I convert my table to be a full 49" X. Its 60" in Y.)

I’m planning to get some shielded wire from Amazon. I’ll ground the shield to the second GND on the unit.

Do I need to run 16g? Or would 18g suffice? I’m not worried about the cost, but it’s the flexibility of the cable that worries me. I don’t want to create any more drag/press-pull on the system than needed. It seems to me like 18g would be more flexible. But if I need 16g I’ll run that.

I figured I’d ask before I (over) buy something I don’t need. The manual isn’t helpful. It says the wire should be between 20g and 15g :man_facepalming:.

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I was running a Vevor spindle on my LR3/LR4 but my VFD was 220v. I have a current clamp on one of the legs going into the VFD. When I was running a 1 1/4" surfacing bit WAY harder than I ever should be I never once saw the current go over 3 amps. So that would be 6 amps on 110v. Now as far as what comes out the other side of the VFD in 3 phase I have no idea. But my brain tells me that it would be fine at 15’ with 18 gauge. But I am curious to see what one of the Electrical Gurus on the forum have to say.

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Thanks Jonathan. I had my son who’s in school for engineering do some calculations and it would seem that 18g over that short of a run should be acceptable. Second related question for the electrical guys.

I run a larger 24V power supply on the underside of my table and just take the 24V up to the Jackpot. Should those power wires be shielded? Since its DC at that point I hadn’t been running anything shielded, but in looking at the VFD cable, I began to wonder if there is any benefit at all. Also - now that there is more variation in the environment (because of the VFD cable) would shielding it create more consistency to Jackpot? (Faraday cages keep RF out as well as in. Does that principle apply to wires?)