CNC Newbie needs advice and Guidance

Hey Christopher,

if you want to run a 2.2 kW spindle on a single-phase circuit with 240 V, then your VFD will be rated to up to 24 A at its input and the recommended fuse will be 30 A (see here for an example of a wire and fuse size table in my VFD manual).

Are you in North America? If so, in most cases you will have split-phase electricity with 120/240 V which means you need a VFD with 200 V class single-phase input and you would need a NEMA 6-30 outlet or a NEMA 14, with a 30 A circuit breaker, for the single-phase input, 2.2 kW 200 V class VFD.

In case you have three-phase electricity with all of the three phases of 208 V made available, then, and only then, you could also buy the 200 V class three-phase input VFD model. This would mean you need smaller wires at the VFD input and a smaller circuit breaker, but a triple contact model then. Should you really have 208 V three-phase, the connectors that are used internationally are the IEC 60309, here they write that in the USA they replace the older American-style three-phase connectors in the last 30 years.

The third possibility, a 400 V three-phase VFD, is for regions where you have 400/230 V three-phase electricity (e.g. Europe)

In any case, I would always recommend to buy a ready-to-use spindle cable with the spindle from the spindle manufacturer (reputable spindle manufacturers always offer this). This is because either you buy an industrial spindle which have an industrial circular connector for which you need an expensive crimp tool (may cost more than the cable) OR you buy a cheap chinese spindle which will come with what they call “aviation connector” in loose form with a piece of cable which is usually too thin for the current and not made for a shielded power cable and it is impossible or at least extremely difficult to fit an appropriate cable into those inappropriate connectors, and additionally, they are for soldering but soldering such a connector is not for beginners. Therefore if you don’t go the route to buy a serious industrial spindle with ready-to-use cable from manufacturer, I recommend to buy a cable ready-to-use for those cheap chinese spindles that are available here.

By coincidence, I just wrote this answer this morning which may overlap regarding content :slight_smile:

Welcome to the forum!

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