VFD Mounting

I think the shorter the wires from the unit to the motor the better.
M
 
You could use flexible armored cable, I do not like to use rigid conduit to a machine. An alternative is to use liquid tight flexible metal conduit and pull stranded wires. I think you would be better off just getting shielded motor cable designed for use with VFDs. The cost is about the same, Automation Direct now sells it by the foot (minimum is 20'). The shield is grounded only at the VFD end, at the motor end cut back the shield and insulate it against shorting with black tape or heat shrink tubing. I uses high quality copper with nylon insulator eyelets at the motor end and for grounds, locking forked crimps at the VFD power/motor terminals. You need a good crimper to fasten the crimps properly. On some builds, I will use 3M heat shrink insulated crimps. You could use 14AWG for 3ph 3Hp motor, but I prefer to use 12AWG, the cost difference is nominal.
https://www.automationdirect.com/ad...le_Control_Cable/12_AWG_Shielded/MCTC-12-4S-1
 
I was thinking about mounting it on the back, or front side of the access panel to the knee column, to the coolant reservoir. I have no plans to run coolant other than my mister.
 
Did you end up mounting the cabinet on your mill?

Not sure if your saw my install, I installed the cabinet on the side of the column, I did this because it was the only place I could make it fit as I didn't have room behind as the machine is against a wall and the Z DRO scale is on the other side.

https://www.hobby-machinist.com/thr...ady-to-start-lathe-mill-shopping.51470/page-5 Starts at post #126

I removed the access panel and mounted it over the opening and was able to use the existing holes without drilling and tapping any new holes.

It worked well, the only thing I would redo is relocate my master ON/OFF switch as it's hard to reach when the table is raised and toward the rear..

I should have installed it on the door.

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No not yet. I'm going to try mounting just the VFD to the inside of the access (coolant) panel. Probably will end up mounting something like yours though. Bought a remote operator, on the fence about if I'm going to use it or not.
 
No not yet. I'm going to try mounting just the VFD to the inside of the access (coolant) panel. Probably will end up mounting something like yours though. Bought a remote operator, on the fence about if I'm going to use it or not.

That's a great idea and I saw someone else mount it inside the column, I did consider that but had already purchased the enclosures so went that route.

Not sure how far along on the install/planning stage you're at but just a heads up, if you run a 4 wire power cable, (3 + Ground) you will be able to have 240 and 120 VAC on the machine to plug in lights, DRO, and Power Feeds, keeps the install tidy and reduces the need to run extra wires back to the wall.

If you look at my picture above I have Red and Black for 240VAC and White and either Red or Black to get 120VAC.
All three enter the box at the bottom right and go through the rotary switch, the 240VAC for the VFD goes through the 30AMP fuses, then to the terminal strip.
The White wire goes through it's own single pole breaker then to the white terminal strip.
I also have a 3AMP double pole breaker for a future 240VAC coolant pump and a 24VDC Power Supply for the fan, digital tachometer and LED lights.

I'll use the empty flex conduit for the 120VAC to a quad outlet at the back of the machine, I was going to mount it on the enclosure but after cutting the holes for the fan/vent, I had no room left so will use an external route.

David.
 
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David. I didn't wire my 240V receptacles with a neutral so that option won't work. My mill sits below a 120V receptacle so everything that is 120 will have to come from there. I just need to get some cable glands and I should be ready to fire it up. Probably won't be until the weekend.
Nice looking control box, I may still do that at a later date.
 
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