Need some guidance on which wire I need to use.

[Sray]

There is a inescapable rule, that any enclosure or cabinet purchased ends up being at least 5% too small !

Don't tell me that. LOL. My original size was 20"x12"x9". Since I am not running a spindle/inverter I figured this would be plenty of room. Fingers crossed!

[Sray]

the Breaker needs to suit the amperage of the Power Supply Plus 125%

So if my PS is 20 amps, does that man I need a breaker that is 45 amps?

Thanks

[mactec54]

So if my PS is 20 amps, does that man I need a breaker that is 45 amps?

Thanks

No, it would be 25A 20x125%=25

[Al_The_Man]

So if my PS is 20 amps, does that man I need a breaker that is 45 amps?

Thanks

Also keep in mind, regulation states that any conductor current rating will be no lower current capacity of any fuse or breaker that it is connected to.

[Sray]

No, it would be 25A 20x125%=25

I had to check because you stated "PLUS" in your statement. I knew it didn't sound right. Thanks!

[Sray]

Also keep in mind, regulation states that any conductor current rating will be no lower current capacity of any fuse or breaker that it is connected to.

Good info. I will keep that in mind and check my wires/cables.

[Sray]

No, it would be 25A 20x125%=25

And just to be perfectly clear for myself and others that are here learning, this means "INPUT CURRENT (of the PS)" X 125%? Not the "OUTPUT CURRENT"?

If this is correct, then my input current of my PS is 8a. So I would need a 10a breaker. In turn, the input cables must be at least 10a?

Shawn

[Sray]

Here is what I have come up with for breakers. Since I am new to a lot of this I would like to make sure I order the correct components.

I have two PS's.

60V/1200W
Input: 110V/8A
I came up with this 10 Amp Breaker (C curve):
https://smile.amazon.com/Chtaixi-Min...93&sr=8-2&th=1


24V/60W
Input: 110V/1.8A
I came up with this 3 Amp Breaker (D curve):
https://www.pioneerbreaker.com/product-p/yc-3-1d.htm

A couple questions.
- Do I need to be concerned with the "Curve"?
- Also the second PS has an input current of 1.8A. I could not find a 2.25A breaker. The closest breaker that was at least 2.25A was this 3A model. Will this suffice?

[mactec54]

I had to check because you stated "PLUS" in your statement. I knew it didn't sound right. Thanks!

Yes, I missed a few words in that sentence the Plus 125% means the Electrical code requirements different types of circuit loadings require different percentage's the 125% covers most of what hobby users need to keep things safe

[mactec54]

Here is what I have come up with for breakers. Since I am new to a lot of this I would like to make sure I order the correct components.

I have two PS's.

60V/1200W
Input: 110V/8A
I came up with this 10 Amp Breaker (C curve):
https://smile.amazon.com/Chtaixi-Min...93&sr=8-2&th=1


24V/60W
Input: 110V/1.8A
I came up with this 3 Amp Breaker (D curve):
https://www.pioneerbreaker.com/product-p/yc-3-1d.htm

A couple questions.
- Do I need to be concerned with the "Curve"?
- Also the second PS has an input current of 1.8A. I could not find a 2.25A breaker. The closest breaker that was at least 2.25A was this 3A model. Will this suffice?

Not on the small Breaker the curve is not important, it is only used for Isolation and Short Circuit Protection, that is all any Breaker is used for

Check your Power Supplies some of these have a built in Fuse so a Breaker would not be needed, the only benefit of a Breaker then is for circuit isolation in your cabinet

[Sray]

Not on the small Breaker the curve is not important, it is only used for Isolation and Short Circuit Protection, that is all any Breaker is used for

Check your Power Supplies some of these have a built in Fuse so a Breaker would not be needed, the only benefit of a Breaker then is for circuit isolation in your cabinet

The smaller PS says "Protections: Short-circuit, Overload, Overvoltage" but that is all I could find.

The large PS says "Protection: OCP OVP SCP OPP" and "Overload protection 105-150% rated power, constant current step-down"

Not sure exactly what this is telling me though. I will most likely get breakers for each anyway, but I would like to know if I really need them.

Thanks

[Sray]

While I am waiting for my cabinet to arrive, I am trying to determine all the additional parts and components that I will need. As mentioned above, I will most likely be adding breakers, E-stops, GND bus bar for the panel (star ground). I see a ton of terminal blocks of all different shapes/sizes/types used in all the photos I have looked at. Since I am running din rails for the small PS and breakers I figure why not also get din style terminal blocks as well.

I am looking at getting this Dinkle Terminal Block Kit. I assume it will come in handy?
https://smile.amazon.com/Dinkle-Term...%2C683&sr=8-21

What other connectors/misc parts should I have on hand?

I just hate having to wait a couple days each time I need to order a specific part. During the mechanical build I was ordering misc parts/screws/brackets/etc every day. Having to wait for all these parts to be delivered has made this build ridiculously long. I would like to be somewhat prepared and have most things on hand.

Thanks

[Sray]

Hi Shaun - The attached video has the driver supplies daisy chained to the power supplies. This is poor practice and is not recommended if you read the driver manuals. Drivers should be connected to PS's individually. Chaining can lead to overheating of the PS to first driver line. Peter

Peter,
I am in the process of creating my electrical diagram and I have a question. You say that drivers should not be daisy chained but instead should be connected to the PS individually. As I am running my conductors between components I noticed that my PS only has 3 pairs of V+/V- terminals but I have 4 drivers that need to be connected. I ask this question because I see so many diagrams where they have two separate PS's for the drivers (2 drivers for each PS) so they each have their own pair of terminal. Can I double up the drivers on one pair of the V+/V- terminals?

Shawn

[peteeng]

Yes Shaun - It has 3 terminals but it is common to have two wires on each terminal. Peter

[Sray]

Yes Shaun - It has 3 terminals but it is common to have two wires on each terminal. Peter

Thanks. Just want to be sure. Don't want to burn it to the ground.

[peteeng]

Hi Shaun - If its a good brand SMPS, these are very difficult to kill. Shorting them will kill it, so be careful with loose wires... Peter

[Sray]

Hi Shaun - If its a good brand SMPS, these are very difficult to kill. Shorting them will kill it, so be careful with loose wires... Peter

I will keep this in mind. Thanks

[Sray]

So I wanted to run my E-stop/breaker diagram by you guys before I get too far into it. This is just the power coming in to the PS's. The E-stop would be mounted to the cabinet. I will install more E-stops for mounting around the machine but those would be installed through the Mesa board.

Please tell me if I am on the right track here. Thanks

https://drive.google.com/file/d/1z1Y...ew?usp=sharing

[mactec54]

So I wanted to run my E-stop/breaker diagram by you guys before I get too far into it. This is just the power coming in to the PS's. The E-stop would be mounted to the cabinet. I will install more E-stops for mounting around the machine but those would be installed through the Mesa board.

Please tell me if I am on the right track here. Thanks

https://drive.google.com/file/d/1z1Y...ew?usp=sharing

Check your Breakout Board, Stepper Drives, Spindle Drive to see what safety circuits input they have, as you may only need to use the Estop for those connections which will all be using a DC circuit, your Home switches will be in this circuit also

[Sray]

Check your Breakout Board, Stepper Drives, Spindle Drive to see what safety circuits input they have, as you may only need to use the Estop for those connections which will all be using a DC circuit, your Home switches will be in this circuit also

OK so I misunderstood what you meant when you said "If you are using a Cabinet of some kind, you would first have a disconnect (Safety Switch) at the Power entrance to the Cabinet, the Power supply from the Switch would go to a Breaker, then from the Breaker to say a DC Power supply". I have seen some cabinets with the E-stop buttons on the door so I assumed that would suffice.

Is this more what you were talking about? If not, can you show me an example?
https://static.grainger.com/rp/s/is/...ger/4B996_AS01

I read these comments on the LinuxCNC forums about setting up an E-stop with the Mesa 7i76e board.

"most estop buttons (well the ones I bought anyway) have two contacts. One is normally closed and the other is normally open.
Wire the mains power to your motors through the NC side and wire field power through the NO side. So when you push the button it cuts the mains power and lights up a Mesa input to tell Linuxcnc estop has been pressed."

"emergency stop cuts motor input power and activates the disable inputs on the stepper drivers. (Note the DC power for activating those inputs must not have its power cut though - the way those disable inputs work on stepper drivers are a bit weird, they should require activation to enable the driver instead!). You probably want to cut the AC side of the motor power supply; DC will require a much beefier relay/contactor not to arc. If you do cut the DC side, pay close attention to the DC ratings of the relay/contactor."

Here is the diagram one person posted. They admittedly messed up the NC circuit but did not fix the diagram. I made the changes to the diagram as I think it should work. Please correct me if I am wrong.
https://drive.google.com/file/d/1liu...ew?usp=sharing

Do the comments make sense and does the diagram reflect those comments correctly?

Thanks