[joeavaerage]

Hi,
the 20A breaker is supposed to protect the house wiring....not your machine. If you want various sections of your machine protected then you should put electrohydraulic breakers IN your machine
cabinet, one for each circuit you wish to protect.

Typically the spindle is the most power hungry device in any machine. Lets say the VFD that drives it has a max input current of 10A, then get a breaker to match it. You might have a second
breaker of 5A say to protect the power supply (for your steppers).

Most people reckon that if the machine Estops that it should kill the power. I disagree. Both my machines, my first mini-mill and my new built machine DO NOT DE-POWER on Estop. I have run both machines
for over ten years without issue.

It was common, even mandatory that industrial machines depower to satisfy safety rules as Al has mentioned...but if this is a machine for your personal use then who cares? Second issue is those rules he mentioned
are for Americans....and who cares what they do....they're all bloody mad!. If I were building equipment for sale I would be applying IEC rules, and they are rather more sophisticated. While in general they do also
perscribe that the machine de-powers they also allow that certain parts of the machine MUST stay energised in order to effect a safe shut-down.

I have relied on my controller (Mach3 firstly and for the last nine years Mach4) to stop all axes, apply the Z axis brake and switch the spindle off when an Estop event occurs, it has never de-powered anything.
I have operated for years that way.......and it has stopped safely EVERY TIME I have Estopped the machine, I mean EVERY TIME.

I have asked if any people have had an instance where their motion control HAS NOT STOPPED when requested, eg and Estop, and no-one has said 'yes my control does that'....so is depowering necessary?

Craig

[jjlee32]

Hi,

Sorry I didn't elaborate more, its just a 7A breaker just to protect the power supply and in turn protect the drivers and steppers (I think), the max input current of the power supply is 6.2 so i overshot a little but I think it should be okay. I am not running a spindle as of right now and don't plan on it for this machine so I just have the one breaker.

For the estop, I figured it was best practice to depower but I don't really have a preference as to if it does or not. I think ill continue looking into what the Mesa card says I'm sure LCNC has something similar where I can have tasks execute once an estop is triggered now that i know that I don't have to cut power. I am one of those mad Americans but this is just a 'hobby' machine and wont be in a production type environment i just wanted to make sure that I don't send 6+ amps through myself if looked at it wrong.

Thanks for the input.