[cspearsall1]

https://www.digikey.com/en/schemeit/...656fe687352808

Can anyone who knows what they are doing critique my wiring schematic and see if I am doing this right? Also, if this is in the wrong spot please let me know.

This is a homemade router with an MB3 breakout board

[CNCMAN172]

The digikey drawing app is so slow it is hard to examine your drawing. Try and convert drawing to a pdf so anyone can view easier

[Al_The_Man]

Is there an E-Stop in there somewhere?
Didn't see one, unless i missed it, a little hard to read.

[cspearsall1]

https://www.dropbox.com/scl/fi/6edoq...rrsmyswj9&dl=0

Here is a link to the PDF file. This should help.

@cncman172 - I put the estops inline after the off button to kill the main power contactor that powers the 48v power supplies for the drives. Is this the right spot? I have seen some setups use an input on the MB3 board but I am not sure how that works.

[CNCMAN172]

https://www.dropbox.com/scl/fi/6edoq...rrsmyswj9&dl=0

Here is a link to the PDF file. This should help.

@cncman172 - I put the estops inline after the off button to kill the main power contactor that powers the 48v power supplies for the drives. Is this the right spot? I have seen some setups use an input on the MB3 board but I am not sure how that works.

The way you show your estop which kills source power to contact or will work. You diagram suggests your spindle is 110v is that correct. I have the same breakout board as you with the ESS

[cspearsall1]

Yes, the "spindle" is just a Porter Cable 3.25 HP router at the moment. I have aspirations to upgrade to an ATC spindle one day but for now this will have to work. I have seen some wiring diagrams that use the estop with a pin on the MB3. How is yours wired?

[joeavaerage]

Hi,
the only thing I see that is missing is a catch diode on the spindle relay. The inductive voltage spike when the relay de-energises will wreck the output of the MB3,
and really spoil your day.

Craig

[CNCMAN172]

Hi,
the only thing I see that is missing is a catch diode on the spindle relay. The inductive voltage spike when the relay de-energises will wreck the output of the MB3,
and really spoil your day.

Craig

In addition to the diodes on the relay to avoid spikes, I would also add EMI filters on the incoming AC power, to avoid EMI interference which will drive your machine crazy, with all kinds of unexpected motion.

[cspearsall1]

@cncman - would this work for an EMI filter or do I need something else?
https://a.co/d/3DNp62B

@craig - I have no idea what a catch diode is, but Google did. So it acts as a one-way gate to not allow voltage back into the controller board from the relay? If you don't mind, can you explain where in the circuit this would be wired and what size I would need for a 15a 100v motor on a relay?

[Al_The_Man]

@cncman - would this work for an EMI filter or do I need something else?
https://a.co/d/3DNp62B

That is good for up to 30amps, R/L/C filters work well to clean up the power line.

[cspearsall1]

@averagejoe - Craig, what size catch diode do I need for the relay on the 110v 15amp 3.25 HP Porter Cable router?

[joeavaerage]

Hi,
the catch diode is for the coil current of the relay, the size of the load that the relay switches is immaterial.

I would suggest, unless you've used an out-size relay, then a 1N4148 or any equivalent signal diode would be fine.
Ordinary 1N4007's (or equivalents) which are standard rectifier diodes work too, but are somewhat slow....but otherwise OK.

Either of these diodes are less than 10 cents each at 100 of quantities. I buy them by the thousand.

Craig

[maxspongebob]

Here is a quick resource for calculating the diode value. Your power contactor may have a recommended value so start there.

BTW, I have always heard of it referred to as a Flyback Diode. Anyhow it is the diode that protects the circuit from the reverse voltage generated by the magnetic field collapse of the relay coil.

https://www.plantengineering.com/art...de-and-rating/

[CNCMAN172]

@cncman - would this work for an EMI filter or do I need something else?
https://a.co/d/3DNp62B

@craig - I have no idea what a catch diode is, but Google did. So it acts as a one-way gate to not allow voltage back into the controller board from the relay? If you don't mind, can you explain where in the circuit this would be wired and what size I would need for a 15a 100v motor on a relay?

Yes, that filter will work fine

[cspearsall1]

Is this where the diode goes?

https://www.dropbox.com/scl/fi/udtx5...l3zbvhep2&dl=0

[joeavaerage]

Hi,
how about posting a wiring diagram I can see?

That filter will work but its only single stage, it should be two stage.

Craig

[cspearsall1]

Sorry Craig,
Hopefully this is better quality:
https://www.dropbox.com/scl/fi/px7s9...9e24f783s&dl=0

[cspearsall1]

Just to clarify. The schematic might be a little outdated now. I am using two contactors, one for the main power and one fed through the e-stop buttons for spindle and motor power (this was discussed a few posts ago in this thread and is not necessarily recommended. When I hit the estop the board remains powered but it kills spindle and motor controller power. I believe I will be changing the estop circuit to just alert the controller so that the router/spindle break can engage). The router is controlled through a solid-state relay using 24V from one of the output pins on the MB3 (Y301).

As I understood Craig, I can use a 1N4007 diode (which I have), but I am using a solid state relay 24V coli controlling 110V for the router, does this mean as @maxspongebob (I'm loving these names BTW) stated that I do not need a flyback/catch diode?

[joeavaerage]

Hi,


NO! Do not put a diode anywhere near the spindle.

A catch diode goes on the coil terminals of the relay.

Scheme-it-export-CNC-Wiring-2023-09-27-07-44 (edited) (1).pdf

Craig

[cspearsall1]

The link to the PDF isn't working for me.