Spindle to pause

I would love the opportunity to pause my 1.5Kw water cooled spindle and go to bed. With routers you have the on/off switch. Not so with the spindle. I have my spindle/VFD routed through the breakout board, but there is no way to pause the carve and … come back in the morning and continue. If one is doing a 15-18 hour carve. basically if you have a spindle you either have to stay up or don’t do the carve. I would love on the next patch to be given the setup option of router or spindle, should you chose the spindle option there should be a “spindle pause” button, this should disengage the spindle, raise it to the top of the ‘Z’ axis and disconnect all commands to the VFD so you can turn off your VFD. When you click the ‘RESUME’ button (having turned your VFD back on) because the program spools up the spindle again, as when you started the initial carve. Please sort this out.


Well if your looking for an ON/OFF switch for your spindle thats similar to a router, then just install one - It’s literally cutting off the supply power. You can either install a disconnect before or after your VFD in a typical setup.

But if your talking about a pause action - Yeah, their still working on that I hear.

All vfd must never be switched between output and the spindle it will destroy the electronics in the vfd, says in all the manuals no MCS no breakers no air switches no isolators on the output of a vfd to spindle, take care

I just want the spindle to be able to pause. NOT turn off the VFD. Is this possible.?

Yes but you have to tell the vfd that the control buttons on the front are ware the control will be from.
If you use the nc code from 1f then you can’t do this as it’s all run from the code.
I’ll update this with what program number if you like you change.

It seems to me you have a couple options that currently would work. One you can configure your VFD to enable the control panel when you are going to do a very long cut. Or you could split up your code into 2 or 3 parts to avoid a very long cut.

Thank you. But please explain it in step by step instructions.


Hey Stuart, hey all,

this is not possible with cheap chinese VFDs (except in manual operator mode, but not with the VFD in ModBus mode), but it is possible with Omron MX2 (PDF Manual) or a Hitachi WJ200 (PDF Manual) (which are practically nearly identical). With these, you can override the ModBus control by CNC controller at any time by a switch wired to the VFD and pause the spindle after having paused your g-code program in the Onefinity Controller, e.g. over night, and switch your spindle back on prior to resuming your program next day. This is described here and here. Note that this does not work with cheap chinese VFDs! With these, you would have to run the spindle all night long / during the entire pause as you cannot override ModBus with them, nor can you switch the VFD off during pause, because when switching it back on, it would have no run / speed set prior to you resuming your g-code program (however unlike the hand trim router, a spindle is so silent that it would not be a problem with noise if it runs all night long with no mechanical load – just in case you want to use cheap chinese stuff)

Please DO NOT DO THIS. Disconnecting vfd from a motor can destroy your VFD most drive manuals should confirm this. if you disconnect your VFD from power, expect this spindles to slow down very slowly because the normal braking system will not kick in. will take maybe 30s instead of 3s to come to a stop.

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Hey jedensmore, hey all,

as you already have pointed out, a switch on the output of the VFD, which means between VFD and spindle, is strictly prohibitive and I have never seen a VFD manual that does not warn about it (however poorly it may be explained or illustrated in cheap Chinese manuals).

Regarding the input side of VFD, in front of the VFD, usual setups have a) a MCCB, b) a magnetic contator to prevent the VFD from starting the spindle after a power failure (can also be prevented in the settings of the VFD) and c) a power switch (often a cam switch), which should have a warning not to turn off the appliance when the spindle is in operation. This can also damage the VFD, as the spindle that is still running immediately acts as an induction generator when it becomes powerless and feeds the current back into the VFD. This warning should also be in every VFD manual (it is in mine). The only correct way to stop a running spindle is the RUN/STOP command (on front panel, or as command via ModBus, or as a switch on an Intelligent Input that has been set to the Run/Stop function). The updated IEC 60204-1 standard explicitly states that the activation of the STOP function of a VFD may be regarded as a category 0 stop. That means “Safe Torque Off” (STO), the spindle is made powerless and therefore cannot exert any torque. This means in this state you can safely take your wrenches and change the bit, you don’t need to power the VFD off.

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