Skip the GX12-6P connector and go direct?

Has anyone skipped using the GX12-6P connector for the VFD control cabling and simply wired direct to the Masso controller here.

In my CNC table arrangement with the OF standard Masso mount, the bottom edge of the screen is so low that it is going to put serious pressure/shear force on the GX12 connector.

I think I will run my cable through the opening in the back of the Masso Touch housing and wire direct to the Masso G3 controller. Naturally I would put some stress relief on the cabling and make sure it is secured properly. Any insights would be appreciated.

In the future if I choose to elevate/move the Masso Touch housing, I could revert back to using the quick connect GX!2-6.

Sort of. I don’t like those cheap connectors, so I swapped them out for mil-spec Amphenol connectors. I’ll probably do so with all of the original connectors, at some point.

Hey Alan,

I just updated my list of tables on how to connect the Elite Masso G3 to various VFDs. Your Hitachi WJ200 is also there. This may be of use to connect them directly.


Greetings Aiph,
Du bist der Beste! “Merci viel mal”.

I assume you would have no quarrel with skipping the cheap connector - right?

1 Like

Bypassing the connector is fine. Honestly, its probably better to bypass it, since the connector is a potential point of failure. I currently have my rotary wired this way. Don’t have to worry about moving the touchscreen and having the connector hit something and snap off. The Masso spindle control doesn’t have any high frequency outputs, so you don’t even have to be concerned with a grounded shield wire.


1 Like

Hey Alan,

a connector is to be able to separate the components, and I see that it would not have the space needed on your setup. And yes, I don’t like these connectors, I prefer industrial circular connectors that are crimped, not soldered, and have gold-plated contacts, from Phoenix :slight_smile:

In the case you omit the connector, you simply skip the connector column in this table and wire the internal Masso G3 pins directly to your WJ200 VFD pins:

1 Like

Thanks Dan, good point you are making there on the shielding. Makes life a lot easier.

I did wire direct to Masso controller’s Spindle Controls terminals and bypassed the low hanging GX12 connector.

I struggled today with the wiring to the Hitachi WJ200 VFD. @Aiph5u, I was not able to get the arrangement in your table to work for me.

This arrangement did. This is the schematic from the Masso Forum (good stuff over there). When I get a minute tomorrow I will follow up with a separate/focused post on this so folks can find it.

Hey Alan,

this is identical to what I show in my table with the exception that here you use +24 V as the common on Masso pins 5+7 (and not 0 V=L=gnd as common), and pins 4 and pin 6 for CCW and CW (source logic),

I used 0 V (=gnd=“L”) as common on Masso pins 4+6, and Masso pins 5 and 7 for CW and CCW (sink logic), because this example from the Masso Documentation website shows it this way:

Image: Spindle VFD examples → Hitachi VFD – Masso Documentation
(It shows the Hitachi NE-S1, but the ports and their labels are identical with the Hitachi WJ200).

You did not show to what your “PLC” terminal is connected, to “P24” (+24 V) or to “L”=gnd=0 V? One question: Where is this bridge (=“short bar”) installed on your VFD, like on the left image or like on the right image:

Both setups should work, but the one I show (the one from the Masso Documentation website) :warning: can of course only work if “PLC” is bridged to “P24”, and not to “L”.

– Source: Hitachi WJ200 or Omron MX2 manual
Image: Wiring on Sourcing vs. Sinking Inputs

Further Reference

– Source: Hitachi WJ200 or Omron MX2 manual

@Aiph5u, The short bar at the VFD is installed as recommended by Masso on the forum and in this schematic. (L/PLC). Take note that Masso’s Spindle Control output terminals 5 and 7 are connected to P24 at the VFD.

This is the forum link if you are a member there. Notice that this post is by a staff member and the gent that does a lot of their videos/youtubes for them (cncnutz). It is very specific to the WJ200 Hitachi. They have lots of other brand/model specific VFD wiring examples in this section of their forum as well.

Hey Alan,

that is why you had no success with the wiring from Masso Documentation website I show in my Hitachi WJ200/Omron MX2 to Elite Masso wiring table. It needs to have “PLC” bridged to “P24”, not to “L”. Try it out, it will work very well. There is also a big hint to connect PLC to P24 on the image of the Masso Documentation website:

Image: Spindle VFD examples → Hitachi VFD – Masso Documentation
(It shows the Hitachi NE-S1, but the ports and their labels are identical with the Hitachi WJ200).

The wiring I show is with sinking inputs wiring and needs to have “PLC” bridged to “P24”.
The wiring you show is with sourcing inputs wiring and needs to have “PLC” bridged to “L”.

:warning: If you combine the wiring of the one with the bridge of the other, it can’t work, that is why I immediately asked you wether when testing my Hitachi WJ200/Omron MX2 to Elite Masso wiring table you followed the hint on the Masso Documentation image to connect “PLC” with “P24” (and not with “L”). I knew that if you omitted that step that would be the reason that it cannot work.

You see that the bridge (=“short bar”) with PLC is different on these two wirings?

I did have the jumper set properly per you table. Unfortunately I misread your table now that I go back and look at it.

I got tangled up in the extraneous info on the PWNCNC cable, pins, colors, etc. I needed only the info in the far left and far right columns since I was skipping the GX2 connector and wiring direct to the Spindle Control terminals on the G3.

Meanwhile, the other recommendation by Masso (via their Forum) works. I need to get some proper cabling and give your table a shot again.

1 Like

Hey Alan,

maybe I also should post a variant of my table that is for direct connection, without the 6-pin GX-12 connector.

G3 ground is at the top right corner on the internal Masso Controller (see image below), I took the Masso terminals labels from this Onefinity diagram:

– Source: Support: VFD/SPINDLE wiring schematic for Elite Masso machines

@Aiph5u, yes I do think it would be helpful to have a simpler table for direct connection.

BTW, I need to figure out what wire #S2 connected to the Masso G3’s “Spindle Output” control terminal in the Onefinity wiring scheme is for.

This wire does not connect to the GX12 connector but runs from the bottom of the Masso Touch where the power is connected from the Onefinity power supply/relay controller. I suspect it may be a trigger wire for the router control relay in the power supply.

Ref. G3 ground - There are several ground pins available on the Masso G3 controller. Wouldn’t G5 work? It is adjacent to the spindle control terminals.

Hey Alan,

even if it’s just connecting the first column to the last column and ignoring all columns between in my table, I see that I should provide an additional table for direct wiring for each of the different VFDs for which I already made a connection table.

According the Masso Documentation, the multiple Ground terminals are all the same. Of course you can use G5 instead of G3.

INFORMATION: There are multiple Power (Red-colored) and Ground (Black-colored) provided on the controller and can be used to easily wire drives, sensors and switches.

The outputs CW (FWD) and CCW (REV) come in two different types: First as TTL-level outputs which have a high or low voltage depending on the logical state (1 or 0), and secondly they are available as terminals of a optocoupler. This is similar to a open collector output, that provide no voltage, the voltage comes from the VFD here, that is why the latter are used to go to the VFD.


Was this helpful from someone who never had a Masso G3 in hands and will never buy one :wink: ?

1 Like

My suggestion is:

  1. drop the information you show on Terminal 3. That terminal is not used in our case here.
  2. Show Terminal 2 as connected to the Onefinity wire #S2. The S2 wire may remain in place if you choose to allow the Onfefinity power supply/relay box to turn on the vacuum. This terminal commands the relay for router and vacuum as appropriate for the planned operation. I do not need this function since my VFD controls the vacuum on/off along with the spindle cooling water cooler.
  3. Show terminal 7 as an optional reversing direction (CCW) command if the user wants to enable that. I don’t have the need for CCW and don’t want the option to run the spindle in that direction.
  4. As you know the ground can be to any of the black ground terminals on the Masso G3. I did choose to use Ground G5

Hope this helps.

Pin 2 enables the external devices vac and router relays on our elite power supply

1 Like

Hey Alan,

what @onefinitycnc says about Spindle port pin 2 means that it is in use by the system and has nothing to do with the connection to the VFD. The opto outputs and the TTL outputs can be used at the same time without intefering.


The TTL outputs pin 2 and 3 are not needed for the connection to a VFD, so I don’t see the reason to include them in my table. In this image that shows the direct connection of Masso to Hitachi VFD, I simply did not show them:

Hey Alan,

in my existing table, I don’t show the Masso spindle port pins S2 and S3 because they are not used for connection of the VFD (they are the TTL outputs). Even if S2 is in use by the system for another purpose, it has nothing to do with the connection to the VFD.

I already show both the CW and CCW pins.

Regarding using G5 ground instead of G3 ground on Masso, I don’t think that someone should put their hand on wiring the internal Masso themselves without having read the Masso Documentation, where it is explained that there are ground pins spread around the entire controller. I would make the table ugly if I listed all ground ports the Masso provides,
but you are right, the G5 ground is nearer to the spindle port so would make more sense.

EDIT: I replaced “G3” by “G1 or G2 or G3 or G4 or G5” in my existing table. This is the most correct information now.

I still need to make a table that only contains the first and the last column that you demanded, for direct connection. But this image shows what the first column and the last column mean in my existing table:

1 Like