Wiring everything up

[AssassinXCV]

I have the HobbyCNC Pro Driver board 4 axis kit.

I planning on purchasing a 36volt 10amp power supply: New 36V DC 10A 350W Regulated Switching Power Supply | eBay

I have two power switches to use:

1. a rocker switch with a indicator light in side rated for 125VAC 16A.
2. 4 Connection E-Stop button (one circuit is closed when unpressed, and other circuit closes when pressed) rated(this is what appears on it:

Ui = 660V AC-15
LTH = 10A DC-13

^what ever that means.

How should i wire up my power switches? I was hoping to be able to have it go: Main>powersupply>rocker>e-stop>Driverboard

But i've read that when closing switches on the DC side of a power supply can result in voltage spikes. YIKES! i dont want to break the driver board so can some one with experience please help me.

ps, i'd use one set of terminals on the e-stop for the 36v into the board, and the other set of terminals for one of the Limit switch inputs. Is that safe? Having that much power so close to one of the Parallel port inputs?

Thanks.

[H500]

Switching the primary side is best. But I would not recommend putting high voltage next to your parallel port. If something goes wrong, you could fry your computer.

[AssassinXCV]

how should i do it so that i dont have to hit two buttons?

[Al_The_Man]

Think of it this way, an E-stop circuit should take care of all power off or shut downs necessary and should all be done with one circuit, a mistake is to look at individual concerns and address them individually.
A typical E-stop circuit would have all the required E-stop activators, i.e. E-stop buttons, over travel, charge pump etc all in one series string, the output of the string, or result, could be a multi contact relay which would power off all items required in an E-Stop condition as well as advising the controller a E-Stop had occurred.
Al.

[AssassinXCV]

okay, that's what i have; a switch that does everything.....

The switch i have is basically two switches in one. you press the button, and one circuit opens(no power go through), and one closes (power does go through)

I use the terminals that when you press teh button, the circuit opens, for the main power to the driver board. so, when teh button is up, power flows. when teh button is pushed, no power flows. This circuit supplies 35v, 10a to the driver board.

Then, the second set of terminals is the opposite. when the switch is up, the circuit is open, so no power can go through. then, when the button is pushed, the circuit closes, and power flows. this circuit is what signals the computer to execute the e-stop command.

aslong as the wires dont short circuit, there shouldn't be a problem.

[doorknob]

One thing to keep in mind - your current plan may not have your e-stop switch stopping your spindle or router, rather it may only be stopping the power to your stepper motor drivers. (But maybe that is being taken care of via a relay on the HobbyCNC Pro board.) I'm sure that you can imagine some emergency situations where quickly shutting off power to the spindle would be critical.

The suggestions that Al_The_Man made are very good ones, and are probably worth investigating in detail.

Do you have any experience working with relays? (Ordinary, "old-school", electromechanical relays, that is...) Using relays is a good way to control several circuits from a single switch. It also permits you to switch high voltages as well as low voltages without being concerned about putting different types of signals in close proximity to each other.

[AssassinXCV]

The spindle i use is a Dremel 4000. I dont think i need to worry about that much of an emergency. I just need the power to the board to stop, and the computer to be signaled. I can easily yank the cord out of the wal if i need to for the Dremel.