What is needed to wire up 2.2kw 220v Spindle and VFD?

The 1F has arrived, so it’s time to deploy all this great advice. Yet I hope for more:

  1. Mechatron’s package included an EMC line filter, which has three “In” connections and two “Out”:
  • In: L1, N and a metal post (ground).
    The 220 service in my wall has four wires. Black, red, white and ground. The cords I see on YouTube have only three (Black, white, green). I assume that folks cut off the female end of an extension cord, and secure B-W-G to L1, N and the post (respectively).
  • Out: Y-connectors on short wires.
    These connect to the VFD posts, L and N. But what about that ground? Do I run a continuation of the “In” ground to the VFD ground? Secure both devices to the same (metal) box? (The mounting holes of the two devices don’t align with each other).
  1. Mechatron’s “Quick Start Guide” also describes a cable clamp for the “motor cables”. The image seems to show one wire within a non-metallic coat, surrounded by a web of fine metal (shield). They say to use an EMC clamp “close to the inverter”. But the purchase included a cable to the motor composed of four wires, each with its proper connection within the VFD. Where is this cable clamp intended to go?

  2. The Mechatron Quick Start Manual shows a Hitachi S1 VFD, but the page is labeled, “Frequency Inverter Omron MX2”. Aiph5u noted the ModBus addresses for the S1 and Omron differ. Maybe that doesn’t matter in the wiring set-up?

  3. Mechatron’s manual for connecting to the CNC controller describes nine links:
    S1, S2, COM, AI2, R01B, R02C, H1, H2 and +24V
    It doesn’t refer to the two RS485 connections that (I thought) are the communication lines. Is Mechatron’s R01B (Digital Input) also called “RS485-”? Is Mechatron’s S1 or S2 (both Digital Output) also called “RS485+”? Or is AI2 (Analog output) actually the RS485 connection?

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Hey David,

I assume that you received a VFD for single-phase input and for the 200 V voltage class. Furthermore I assume that you are in North America which would mean you probably have Split-phase electricity, which means 120 V between one hot and neutral, and 240 V between two hots of different phases. Therefore you have to connect the both inputs L1 and N of your VFD to two hots of your wall box, and ground to ground. Note that you do not connect anything to your neutral, I repeat nothing, since you want to use your 240 V and not your 120 V.

As for identifying the wire colors, here you see the international colcors and those common in North America:

– Source: Electrical wiring # Colour coding of wiring by region – Wikipedia

Okay when we lookup in the table above, so in the USA:

Black is Hot (Phase 1)
Red is Hot (Phase 2)
White is Neutral, and
Green is Ground.

So what you want here, is to connect a single-phase VFD to a single phase 240 V power source which you find on your two hots of different phases. Therefore you wire your

Black (Hot1) ----> L1 on VFD,
Red (Hot2) ----> N on VFD (sic!),
White (Neutral) to nothing (important, since you don’t want any 120 V here), and finally
Ground ----> Ground on VFD/EMI filter.

Selecting wire and fuse size

Now for choosing the wire strength. The wire is always dimensionated according to the current. If you want to know what current your VFD will draw, you take a look at the VFDs nameplate, and look into the VFD manual (PDF):

Hitachi_S1-00130SFE_nameplate

Image 1: Nameplate of the Hitachi VFD model S1-00130SFE: 24 A input in normal duty (ND) mode.

Hitachi_S1_manual__Rated_value__2.2_kW_model_highlighted

Image 2: Excerpt from the Hitachi S1 manual: For model S1-00130SFE: 24 A input in normal duty (ND) mode.

If you think, why is that so high, note that if you have a VFD with single phase input (which is necessarily the case here if you have Split-phase electricity), then all the power has to be provided over the single phase, which means it draws more than double the current on one input wire than it would if you had a VFD which receives power over a three-phase input. Therefore usually you would always prefer a VFD for three-phase electricity (that’s what is common here in Europe), since you would not need such thick wires and such a strong fuse, but unfortunatly three-phase electricity is rare in North America.

Now for wire and fuse size. I noticed you don’t have a table for the wire sizes in your VFD manual. But you can take the table I provided above in this thread (search for 200 V class, Single phase input, CT mode, 2.2 kW motor output):

So for your 2.2 kW 200 V class VFD with single input, which draws up to 24 A (=5.7 kVA) input in normal duty (ND) mode (as shown from your VFD manual and on your VFD nameplate), you would need a three-wire (2+PE) 10 AWG cable.

I don’t know what is shown on youtube but you need a three-wire (2+PE) 10 AWG cable as described above.

I don’t know if you want to connect your VFD installation directly to your wall box or to a plug, but in the latter case the correct plug/socket would be NEMA 6-30 or NEMA 14-30 in the USA.

How to attach the EMI filter and the VFD to the power is already answered above.

Well if the mounting holes of the EMI filter and of the VFD don’t align, then Mechatron probably went out of Hitachi WJ200 and Omron MX2 (which exactly match to be mounted on top of the EMI filter). At the time I bought my spindle, they sold the Omron MX2 with it, but due to the worldwide suppliers problem, many VFDs ceased to be available. But that does not matter, you don’t forcibly have to mount the VFD on top of the EMI filter, you secure both the EMI filter and the VFD to the mounting plate of your control cabinet side by side, as Mechatron does too by the way, as shown here:

Regarding the shielded spindle cable, its shield should be clamped to ground (see picture below) or grounded with a grounding cable gland.

Where the four wires have to go should be clear:

1)

The four wires of your shielded spindle cable go to U,V,W and PE (⏚, ground) of your VFD, and the shield of the shielded spindle cable should be clamped to ground (see picture) or grounded with a grounding cable gland.

You should have one central grounding point, which usually is on the mounting plate of your control cabinet. You attach both, the VFD and the EMI filter, on this mounting plate, and the shield of the spindle cable somewhere onto this mounting plate too, near to the VFD. See the image below.

Don’t you have access to the shielding of the spindle cable? As I make my own cables, I don’t know how the cables Mechatron manufactures exactly look like. Can you provide a photo of the end that goes toward VFD?

No, it doesn’t matter.

To connect your Hitachi S1 VFD to the Onefinity CNC Controller, you just need to connect

The RS-485 port on your VFD is located here:

– Source: Hitachi S1 Series Basic Guide (PDF)

The connections you listed are some digital and analog control lines witch which you can control the VFD in case your CNC controller has no RS-485 / ModBus interface, e.g. as with Masso controllers. But if your CNC controller has a RS-485 / ModBus interface (which is the case with Buildbotics and Onefinity controllers), you need nothing else to let it control the VFD than these two wires. The Onefinity Controller will also stop the spindle over RS-485/ModBus when entering “estopped” mode.

Another topic would be automatic dust collector and coolant pump switching, which I tried to summarize here

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Aiph5u gives great help and references. I just ran across a video for those of us who are ‘visual learners’:

How to Wire a VFD | VFDs.com

I put my 1F stand on casters so I can rotate it for larger projects. That calls for move-able electrical connections. I’m thinking that if my wall box (with 220v power) has a 3-prong outlet, I’ll have the required ground and two “hot” leads. The common ones are 10-30r, but that’s rated for 30A and the manual calls for a 40A breaker. There are also 10-50P. Is my plan reasonable? Is it wisest to use an outlet rated higher than the breaker?

Out of curiosity, what was the investment for the Mechatron spindle? I’ve sent an RFQ to them, but haven’t heard back yet.

The spindle cost 816 Euros. Lately, the exchange rate with USD has been better (for people who hold USD) than for the last 20 years. That said, the difference is about 10% from what it was a few years ago. It’s a big deal to banks and the government, but by no means a ‘steal’ for tourists and woodworkers.

But there are other costs. The Hitachi S1 VFD cost 590 Euro, the cooling system cost 700 Euro. There are various other items (50-100 Euro) such as cable, line filter, collets, etc. There’s also a tariff (paid to the US) of about $200. All in, with the options I chose, the cost was 2800 Euros. If you know electronics, the same VFD is advertised for much less on line. Mechatron paired it with their spindle, which an experienced user could do for themselves.

I was slow to realize how much other buyers of spindles know about the required electronics (and I don’t). I’m now sourcing a console to house the parts that need protection from dust, as well as relays and power units (because I want a vacuum and the cooling pump to turn on when the spindle does). Aiph5u has been great, but I’m so new to the topic that my questions are wearing out the patience of these knowledgeable folks. On a lucky note, I found a relative of an in-law who is a “Controls Technician”. That’s apparently the specific job title of people who make machinery work for businesses. Were it not for him, I’d probably look for a Controls Technician to pay for consulting on this small job.

When I start asking why I dove so deeply into a pool like this, I remember that my CNC interest is in making clock dials (brass) for clocks. That task really can’t be done by a router. Local pro shops want to charge me $300 each for a dial.

The Mechatron company is fairly small. You might try sending an email to the attention of “Anna Orth”. She handled the purchase for me.

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Hey David,

if you have NEMA 10 outlets, you have 120 V and 240 V (hot1, hot2, and neutral), but no ground, that’s why they are deprecated. Neutral is not a replacement for Protective Earth (ground)!

That’s why I said above:

If you have a certified electrician there in the U.S., that would be the best, he can safely advise you on which socket to use best. I am only familiar with the regulations and sockets in the EU!

The relevant information is what we have seen in the post above: A VFD with single-phase 200 V class input which draws 24 A in ND mode and 30 A in LD mode, and as you already reported, it recommends a 40 A fuse for single-phase input based on “The capacity of the breaker needs to be 1.5 to 2 times the rated current of the inverter.”

do not worry, they are not, but I have a lot to do at the moment and not much time for the forum. :slight_smile:

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Hey all,

aw, the link in the post above ceased to work. They changed the URL again:

Here is the current and working URL to this highly recommended document:

Begin with the End in Mind — Proper VFD Cable Termination

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