External E-Stop

This is what I use. For simplicity it connects to everything except the shop vac, which is on another circuit. So pressing this will kill power to the CNC controller, VFD for spindle, water cooling, computer, monitor, etc.

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That’s a pretty good idea… like a router table on/off switch.
Do you notice any interference with the controller, monitor, pc & vfd on the same circuit?

That is exactly what it is. I think I picked it up on sale at Rockler.

I haven’t had any issues having that all on one circuit.

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Is it confirmed that the ‘e-stop’ on the controller actually interrupts line voltage? If so wouldn’t a simple e-stop paddle connected to a power strip (that supplies power to the controller) suffice as an external e-stop?

I am wondering the same thing.

I am finalizing plans now and considering mounting my controller underneath and out of the dust.

Exactly, and additionally, the router could be plugged in to it as well allowing for it to be powered down via the same action.

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I just ordered one of these for a custom power-controller box I’m designing (or I might just use a standard electrical box). Also considering the under-table mounting option for the Onefinity controller as mentioned above.

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OK… so that was an ill-advised purchase. That POWERTEC 71577 230V Magnetic Paddle Switch I linked to above is not grounded, so I’m not going to mess with that. I should have gotten the one @garrett1812 purchased (Rockler). I’m going to do that, now.

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If you get a Breakout Board Adapter from Onefinity or Amazon if you use pins 23 and 25 this is the logic circuit that is attached to the e-switch, by all rights this will do exactly like the E-switch. Then all you would need is a momentary switch that would interupt the circuit until it is reset.

PowerTec makes a 120v version of that switch. I got one off Amazon not long ago for my jointer when the OEM switch died and going to Deltas parts site the switch was NLA. So I went with the PowerTec magnetic switch and I like it over the OEM switch.

A big plus is it’s a magnetic switch, so if the power drops out for whatever reason your tool is not starting up again on its own. And it seems to be a better quality switch than Delta put in to begin with. After I bought that one I bought a couple more for other 120v power tools in the shop and one for my router table. I have one more that I will use as a master power/E-Stop for the CNC. It’s rated at 15A so might not get more than the spindle on there but that would be the biggest concern for me from a safety perspective.

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That’s only rated for 1/2hp - the Makita is 1 1/4. Is that an issue or is it a different type of motor?

You can get this one which is listed with UL and rated at 16A.

Or this one which is for 120v or 240v single phase.

And they have a bunch of other style switches with various volt and amperage ratings.

Yeah, I saw that one. The others are 16A 1/2hp rated. Probably would want to buy two so I could swap the paddle out of the lower rated one and put it on the good one. Although might be able to make a paddle on the 3D printer or laser too.

Look at the POWERTEC 71007 110 V to 220V Paddle Switch.

RATED: Single phase, Dual voltage 110/220 volt smart switch,
2 HP/35 amps at 120 volts; 3 HP/20 amps at 230 volts

Yes, the Makita draws 6.5A according to the spec sheet.

Makita RT0701C Router Spec Sheet.pdf (721.5 KB)

But it’s a 1 1/4 hp motor. I know that different kinds of motors have different current demands on starting so that was why I was asking whether the motor in the Makita was of such a kind that the switch’s restriction to 1/2 hp was material. Most motors are rated at running or continuous power, not the startup power. That was a factor in sizing the generator for my house - refrigerator, forced air heating blowers and well pump motors for instance draw a substantially higher load on starting than when running.

I like the magnetic switches due to your original point that they won’t allow the motor to restart once the power to the circuit is restored. You have to physically switch it off/on. Just not gonna do me any good if the power draw on the router at start is going to toast the switch.

Use what you feel is safe for you.

Yes, the starting or in-rush current of the Makita router will exceed the 6.5 running amps.

That’s no different than a 1/2HP induction motors’ starting amp draw.

What do you think happens with a 1-1/2 HP induction or capacitor-start motor?

The universal motor in a router is much different than an induction motor.

I am considering the addition of an external E-stop also because the controller is mounted under OF’s rolling stand. I would use the E-stop terminal in the breakout concoction on the back of the controller but this is used to control my VFD. Now the option to kill the main power via an E-stop kill switch seems to be the obvious solution. My concern is OF highly recommends not killing the power without a software shutdown as the Raspberry pi may loose its mind. I guess by definition “Emergency” means hit the red button. Now that being said if the PI lost it mind, I have it backed up through the OF screen but if its functions aren’t working how could it be restored Hmmmmm. Sorry rambling.

Hey Richard,

usually you control the VFD over the ModBus serial port on pins 13 and 14, so pin 23 ‘estop’ should still be free. Or do you want to say that you have used ‘estop’ pin 23 for something in conjunction with the VFD?

Yes, that indeed is not recommended, but Onefinity contradicts itself with the fact that the big red Emergency Stop button on top of the case is wired to simply cut the power to the controller at the internal power supply, as Onefinity stated here. In contrast to what you would assume, especially when knowing the Buildbotics Controller of which the Onefinity Controller is a fork of, on the Onefinity Controller the big red button it is not connected to “estop” (pin 23) functionality of the Mainboard. But of course you can wire it that way. Then after hitting the red button you would retain a running Raspberry Pi with the CNC Controller Application in “estopped” mode, i.e. with spindle stopped.

Further reading

Hitting Emergency Button on top of the Onefinity Controller box
Best way to e-stop spindle and VFD?
Estop Wiring Via Breakout Board

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Thank you for your input. Yes I do control the VFD via modbus pins 13 and 14. this works very well especially with a 5 second delay to come up to speed before continuing, I believe the answer is using the pin 23 as a soft E-stop. I am working on a solution as my controller is mounted under the spoil board (on a rolling stand) and the cable from the 25 pin DB connector to my VFD is disconnected from the controller every time I stow the machine. I would like the new input to the pin 23 (e-stop) mounted on top of the spoil board with easy access. I am thinking the input to pin 23 will have to be a pig tail at the 25 pin connector and a quick disconnect to the E-stop. Again thank you for your input.