electronics question

[eloid]

need some help with estops, i want to wire up a few relay to break the spindle power and the power to drives.... this is my frist project need some HELP! I just dont want to relie on the break broad for e stop and mach?

Not sure if i should break the power to the drives only or the break out brd also. Does anyone have a schematic i can review...Im more of a hands on
guy...

[H.O]

Hi eloid,
It's really hard to come with a generic thing that works for everybody since all systems are different. I took a quick stab at it and the result is in the attached screenshot.

S1 and S2 are two E-Stop buttons (normaly closed of course)
S3 is your enable switch, press this to enable the system.
S4 is used to override the limit switches so that system can be enbaled in order to jog off the limits.
S10-S15 are your six limit switches, add or remove as you see fit.
S16 is another switch you can use for whatever you want to - safety door or or what not.

Is that somewhere close to what you are looking for?

EDIT: Schematic removed, see better version in next post.

[H.O]

eloid,
Here's a better, cleaned up shematic.

If you press E-stop, hit a limit or open the safety door the machine will cut power to the drives and to the spindle. To enable it again simply press the reset pushbutton. If you are on a limit, press and hold the limit override pushbutton, enable the system and jog off the limit switch, then release the override pushbutton.

Signals are routed to the break-out-board to inform Mach3 of an E-stop event and if it was due to a limit being hit or the door being opened.

The safety door is just an example, you can use that switch (or a series of switches) for anything you like. Overtemp protection of the drives or spindle motor? Spindle overload? Coolant tank empty? YMMV

Hope this helps.

[ger21]

H.O., Can you post a .pdf of that as the .jpg is very hard to read.

[H.O]

Gerry,
Oh crap, it looked fine on my computer. I exported it as a .gif but apparently it got converted to a .jpg when uploaded. I'm away during the weekend but I'll post it as a .pdf on Monday. If there's anything in specific you want to know (or sugestions) just let me know.

/Henrik.

[H.O]

Hi,
Attached is a .pdf instead of that crappy looking .jpg. (It was fine when uploaded as .gif but....)

Anyway, I cleaned it up a bit further and added coolant control (K7, F3) as well as switches for coolant and lube level (S17, S18, K4). These switches, when tripped, won't cause an E-stop but will prevents the system from being enabled again until the problem is fixed. I also added a switced bleeder (R1) for the motor powersupply. This will discharge the main capacitors when ever the system is disabled.

You can do so much with this but this, I think, is a pretty basic, yet very functional way to wire up a system. Of course you can add or remove stuff as you see fit.

/Henrik.

[CarveOne]

Thanks, that's readable now. The light gray text is harder to see than the black text though. In the PDF version I can read it clearly when zoomed in enough.

CarveOne

[eloid]

Frist of all thank you for the drawing... great job

Need a quick explainaton....on a few things

1 why do you needa rest switch and reset inhibit explain wha advantage is there having it...

2.. limits ok k2 not sure pls explain

3. from what i see in general most people dont plud the power to the drive motors? cus u lose you breaking step? to stop? thus you will not stop
always where u want to resume.....

if i want a pause feature i wire it like a estop?

Originally Posted by H.O Hi eloid, It's really hard to come with a generic thing that works for everybody since all systems are different. I took a quick stab at it and the result is in the attached screenshot. S1 and S2 are two E-Stop buttons (normaly closed of course) S3 is your enable switch, press this to enable the system. S4 is used to override the limit switches so that system can be enbaled in order to jog off the limits. S10-S15 are your six limit switches, add or remove as you see fit. S16 is another switch you can use for whatever you want to - safety door or or what not. Is that somewhere close to what you are looking for? EDIT: Schematic removed, see better version in next post.

[H.O]

Originally Posted by eloid 1 why do you needa rest switch and reset inhibit explain wha advantage is there having it...

The reset switch is what engages and latches K1, in other words it turns the system ON. The reset inhibit is used to prevent the system from being enabled if K4 isn't engaged. K4 is engaged when both the coolant level and lube level switches are activated - ie, there's coolant and oil in the tanks. The idea behind this is that it may not be necassary to issue an E-stop (ie instantly stop and disable the system) just because the lube tank runs empty. On the other hand it prevents you from starting the system again until it's fixed. Does that make sense?

2.. limits ok k2 not sure pls explain

The limitswitches controls the relay K2: One of K2's contacts (11-14) is in series with the E-stop and will stop the system if one or more limits are tripped. Another of K2's contacts (21-24) switches +5V to the breakoutboard to inform Mach3 that a limit is hit. If you don't want the signal to Mach3 you could just wire all the switches in series with the E-Stop and skip K2.

As I've said before, threre's SO many different ways to wire a system like this and each has there own preferences. YMMV

3. from what i see in general most people dont plud the power to the drive motors? cus u lose you breaking step? to stop? thus you will not stop always where u want to resume.....

Again, it depends....If it's a servo system you definetely want to cut the power to the drives, if you don't there's no way to stop the axis in case the motor runs away due to a faulty servo-drive etc. In a stepper system it's safer to leave the power to the drives ON because it's VERY unlikely a stepmotor drive will fail in a way that will cause a motor to run away.

In any case you generally can't resume a program after E-stop or Stop without re-homing because the pulse-stream coming from Mach3 is abruptly halted when you E-stop (or press stop) and the motors will lose position. The bleed resistor R1 will help break the motors by absorbing the energy returned while they coast to stop.

if i want a pause feature i wire it like a estop?

No, if you wan't to pause and be able to safely resume again you should use Feedhold. If you press E-stop or Stop you generally need to rehome, then move the machine close to where you want to resume and then use the Run from here feature in Mach3 to resume.

Does that make more sense?