[ihavenofish]

The delta manual should show wiring configs. Also check the delta NC300 manual (their control) for more practical diagrams. One contactor / breaker in front of all drive power stages that is enabled by the e stop loop is likely the easiest setup. There might also be an option line choke / filter / isolation transformer in there drawings as optional.

For example the brother (and my maho except that was far more complex), you turn on the main switch and "nothing" happens. you hit the power button on the panel and the control turns on/ The control in turn enables the e stop circuit and the drives turn on. If I'm in overtravel the control shows me an error and the contactor is off in the cabinet. When I converted the brother to linuxcnc it was very fussy about the timing and order of turning things on as well (I never changed anything in the machine except the cables to the original control)..The drive control voltage (little r and t) needed to come on some milliseconds before drive power voltages (big R-T). So the control voltage winds up on a separate circuit to the contactor on the main drive power voltage. Delta should have timing diagrams in the manual. It's very confusing to write out, but the diagram makes sense.

This seems to be the norm I've encountered, however there are probably hundreds of safe ways to do it.

[ihavenofish]

On the home... there's again 500 ways to do this. In the most basic form, you need a switch to trigger a home sequence, and a switch to trigger hard limits. Home allows the machine to register itself, and the control sets its own "soft' limits it he axis. Hard limits trigger E stop and kill the machine in an emergency. ideally you'll never hit them.

Technically you could make the home and a limit switch the SAME physical switch, but this can be tricky as you could home the machine, turn it off, and then not be able to turn it back on until you manually push the axis off the switch.

Basically, easy router is one precision inductive switch for home, and one mechanical switch with 2 dogs to trigger it for hard limits. You can also use inductive for all 3, but I *think* mechanical is still recommended for e stop hard limits (safety).

[ihavenofish]

24V psu in your case can be 60W, 120w. it doesn't need much. It's running IO and the Z brake release and little else. If you had an ATC with solenoids and coolant valves etc, you might need to upsize.

My little machine in that video runs a 240W 24v psu for the control AND the axis servo power (180w x3). Should be using a 480 really, but it still barely gets warm. The DIN psu's are rated to spec unlike the cheap little brick ones. When it says 120w, it MEANS 120w, full load, no sag, often with detailed overload specs. Mine for example can do 360w for 5 seconds every 30 and 480w for 1 second every 11 (just going on memory, its probably not quite that). It has a defined duty cycle just like the servos. The cheap brick psu's say 120w and MEAN "120w for 1ms before it catches fire". So there's a reason they cost a lot, not just cause of the mount.

[TeeTomTerrific]

On the home... there's again 500 ways to do this. In the most basic form, you need a switch to trigger a home sequence, and a switch to trigger hard limits. Home allows the machine to register itself, and the control sets its own "soft' limits it he axis. Hard limits trigger E stop and kill the machine in an emergency. ideally you'll never hit them.

Technically you could make the home and a limit switch the SAME physical switch, but this can be tricky as you could home the machine, turn it off, and then not be able to turn it back on until you manually push the axis off the switch.

Basically, easy router is one precision inductive switch for home, and one mechanical switch with 2 dogs to trigger it for hard limits. You can also use inductive for all 3, but I *think* mechanical is still recommended for e stop hard limits (safety).

My assumption is that home can be programed to be 10 to 20 mm from the switch like my 3D printer. When you home it, it travels to the home limit switch then moves to the home position about 10mm away from the switch. If cannot do this then I'll rethink my switches. Perhaps someone with more knowledge about UCCNC can chime in on this.

[TeeTomTerrific]

24V psu in your case can be 60W, 120w. it doesn't need much. It's running IO and the Z brake release and little else. If you had an ATC with solenoids and coolant valves etc, you might need to upsize.

My little machine in that video runs a 240W 24v psu for the control AND the axis servo power (180w x3). Should be using a 480 really, but it still barely gets warm. The DIN psu's are rated to spec unlike the cheap little brick ones. When it says 120w, it MEANS 120w, full load, no sag, often with detailed overload specs. Mine for example can do 360w for 5 seconds every 30 and 480w for 1 second every 11 (just going on memory, its probably not quite that). It has a defined duty cycle just like the servos. The cheap brick psu's say 120w and MEAN "120w for 1ms before it catches fire". So there's a reason they cost a lot, not just cause of the mount.

This is one of the reasons I picked the MEAN WELL brand and the DIN rail form factor. I linked to the spec sheet in my original post and it shows exactly what you the type of performance you mentioned, (full load, no sag). It's not that expensive though. $45 from Amazon.

[ihavenofish]

This is one of the reasons I picked the MEAN WELL brand and the DIN rail form factor. I linked to the spec sheet in my original post and it shows exactly what you the type of performance you mentioned, (full load, no sag). It's not that expensive though. $45 from Amazon.

$45 is alright. My 240v delta was $87cdn when i got it a few years ago. Now it is.. *checks digikey* $135 and has been out of stock every time I've looked for over a year. Almost no delta psu's are in stock. I assume its partly chip shortage stuff, but also the large-ish amount of copper inside them.

[ihavenofish]

My assumption is that home can be programed to be 10 to 20 mm from the switch like my 3D printer. When you home it, it travels to the home limit switch then moves to the home position about 10mm away from the switch. If cannot do this then I'll rethink my switches. Perhaps someone with more knowledge about UCCNC can chime in on this.

You still have the issue of hitting the hard limit which should be tied to e stop. I agree though you need to first see how uccnc handles it.

[TeeTomTerrific]

The delta manual should show wiring configs. Also check the delta NC300 manual (their control) for more practical diagrams. One contactor / breaker in front of all drive power stages that is enabled by the e stop loop is likely the easiest setup. There might also be an option line choke / filter / isolation transformer in there drawings as optional.

For example the brother (and my maho except that was far more complex), you turn on the main switch and "nothing" happens. you hit the power button on the panel and the control turns on/ The control in turn enables the e stop circuit and the drives turn on. If I'm in overtravel the control shows me an error and the contactor is off in the cabinet. When I converted the brother to linuxcnc it was very fussy about the timing and order of turning things on as well (I never changed anything in the machine except the cables to the original control)..The drive control voltage (little r and t) needed to come on some milliseconds before drive power voltages (big R-T). So the control voltage winds up on a separate circuit to the contactor on the main drive power voltage. Delta should have timing diagrams in the manual. It's very confusing to write out, but the diagram makes sense.

This seems to be the norm I've encountered, however there are probably hundreds of safe ways to do it.

So the diagrams below are from the Delta Manual for my Drives. They suggest using an EMI Filter and specify a Delta part number EMF023A21A which I have not yet been able to find a vendor for, but I'm assuming that there is probably an equivalent Filter from another manufacturer I can use if the part they specify is not obtainable. They also mention several places about an optional regenerative resistor, but it has a built in resistor so I'm unsure why I'll need and external resistor since I probably will be not running the motor at 3000 RPM but more like 1800 to 2000. But perhaps I misunderstand the reasoning for the external resistor. It appears I can run the power to all 4 motor drivers using a single breaker and contactor switch but the diagram for that shows external resistors again in the loop probably to enable sharing of regenerative energy which may be the reason for using the external resistors.

I'm unsure about the Alarm Relay B. It must be built-in the Magnetic Connector switch? There is a second Alarm Relay connection coming from the I/O cable from the board which I assume forces a shutdown somehow but that is not yet clear.

I'm definitely a novice when it comes to this type of electronic wiring. I know how to size breakers and wire for a 220 circuit. Pull wire make connections to breakers and receptacles, but I have next to zero experience with these kind of connections to electronic devices and def don't want to fry anything by doing it wrong. All I really know is 220 is two hots and a ground wire. My electrical knowledge beyond that is sparse.

[ihavenofish]

Quickly:

- The filter is going to have a basic spec, should be standard from many sources. It is optional and really depends on your mains power/shop space. If its flakey or your shop has tons of interference (welders etc) then the filter is needed. My delta MS300 VFD has the filter built into it which was nice.

- There is a regen resistor is inside the drive. IF you have very high decelerations, you may need a larger one. This is where the external one comes in. My Brother for example used a combined 1KW resistor (2x500w) for all axes and the spindle. 90% of that was for the spindle (150ms from 6000rpm to 0). I do not know if it is more ideal to share a resistor or to have one each drive (the brother obviously shares). You need to find the math to see if you need an external and how big it needs to be. Yaskawa's calculator will tell you this for *their* drives. Not sure if delta has a tool or the yaskawa numbers can be applied to delta drives.

- Regen sharing is new on these delta drives, I don't know much about it. The principle is to share a DC bus so regen from one drive can feed another instead of shunting it to waste heat in a resistor. I have no idea how you are meant to set it up though or if you should.

- The alarm is not really applicable in that way. Under CNC control you would wire the alarm / back to the control to stop the system. For example if you crash it should alarm and tell the control which will cut out. You *could* wire it to the E stop system as well I suppose, but that can get complicated. You should devise your E-stop circuit and all failure modes you want to capture.

[ger21]

My assumption is that home can be programed to be 10 to 20 mm from the switch like my 3D printer. When you home it, it travels to the home limit switch then moves to the home position about 10mm away from the switch. If cannot do this then I'll rethink my switches. Perhaps someone with more knowledge about UCCNC can chime in on this.

Yes, you can have UCCNC do this.

[ihavenofish]

Yes, you can have UCCNC do this.

But does that same switch being connected to E stop cause an issue? (same switch for hard limit and home)

[ger21]

All I really know is 220 is two hots and a ground wire.

In the US, it's actually 240V, not 220. :nono:

[ihavenofish]

In the US, it's actually 240V, not 220. :nono:

240, 220, 208, close enough. :P

I assume most new gear just "handles it" but the brother isolation transformer from uh.. 1990? had at least 8 incremental taps for anything from 200 to 250v. Pretty cool actually. I assume the sanyo drives did not have a very wide tolerance.

[ger21]

But does that same switch being connected to E stop cause an issue? (same switch for hard limit and home)

So I think what you are asking is if the limit input is ignored during homing? I'm pretty sure it is, or you couldn't use the same switch for a home and limit.
When you say Estop, are you also saying to use the same switch for an Estop input? So the switch will be assigned to 3 inputs - home, limit, and estop? In that case, my guess is that it won't work. But there would really be no point in doing that, as the limit switch input does the same thing.

Imo, it's much easier to have a separate mechanical limit switch beyond the home switch.

[ihavenofish]

So I think what you are asking is if the limit input is ignored during homing? I'm pretty sure it is, or you couldn't use the same switch for a home and limit.
When you say Estop, are you also saying to use the same switch for an Estop input? So the switch will be assigned to 3 inputs - home, limit, and estop? In that case, my guess is that it won't work. But there would really be no point in doing that, as the limit switch input does the same thing.

Imo, it's much easier to have a separate mechanical limit switch beyond the home switch.

Yeah I mean if its wired to e stop. (hit the switch, stop the machine).

I guess it makes some sense, you either have 2 separate switches, or, you forgo a hard stop switch which is actually what I've done in the past with my routers. They didn't have the motor power to break anything though, ha. I don't rerember how my novakons were connected, I never messed with them. Pretty sure it was a single inductive switch.

[TeeTomTerrific]

I interpret the answers then as 2 mechanical limit switches per axis screw, (8 total), that are tied to the E-stop circuit to prevent a malfunctioning motor from causing damage and 1 inductive switch per axis for homing, 1 for x, one for y and 1 for z. The y one can be on either side, but does not need to be both.

Are the e-stop limit switches wired to the controller individually?
Should the e-stop be NC so if there is a broken wire the circuit would be open?

[ihavenofish]

I interpret the answers then as 2 mechanical limit switches per axis screw, (8 total), that are tied to the E-stop circuit to prevent a malfunctioning motor from causing damage and 1 inductive switch per axis for homing, 1 for x, one for y and 1 for z. The y one can be on either side, but does not need to be both.

Are the e-stop limit switches wired to the controller individually?
Should the e-stop be NC so if there is a broken wire the circuit would be open?

I think that interpretation is wrong.

We are talking about separate switches for home and limit. You can still have one limit switch that activates at both ends of the travel (one limit and one home per axis). Home here is separate. The other option we were talking about was home NOT being separate (1 induction switch per axis and nothing else).

As for wiring, there's a million ways. In my head, NC makes sense if you think of it as a chain. You only want the chain to break when the switch gets hit.

[ger21]

Are the e-stop limit switches wired to the controller individually?
Should the e-stop be NC so if there is a broken wire the circuit would be open?

If you ask 100 hobbyists, you'll get 100 different answers.

The "proper" method, is to have an E-Stop circuit, which is NC, with everything in series, and controls the main power contactor. So if anything triggers the E-Stop, it takes out power to the system.

If you do it this way, you don't even need to wire them to the controller, but the controller won't know when you hit a limit.
What most hobbyists do, is wire their limits to the controller, and rely on the controller to stop the machine when a limit is hit. This is usually fine with steppers, but if you have a runaway servo, lots more damage can be done if it does not get stopped.

The y one can be on either side, but does not need to be both.

You want a switch on each side of the gantry, so the gantry can be squared to the switches when homing.

[ihavenofish]

You want a switch on each side of the gantry, so the gantry can be squared to the switches when homing.

Ah yes, missed that line. Most of these controls will do some sort of independent homing to square up. moves home, hits the first switch, homes to that one "synchronized", and then rehomes the other side using only that side's motor and switch. This is one place it pays to have a very adjustable home switch, because you don't want it racking any significant amount (my little machine would break itself if it was racked more than 0.5mm).

[dazp1976]

If you ask 100 hobbyists, you'll get 100 different answers.
What most hobbyists do, is wire their limits to the controller, and rely on the controller to stop the machine when a limit is hit. This is usually fine with steppers, but if you have a runaway servo, lots more damage can be done if it does not get stopped.

Can't trust control alone to deal with it.
I'll be using a limit as a home so hmmm.

I'm looking at an override switch setup that you have to physically hold in for it to ignore the limit while homing.
If something goes a miss, just release it quick.

Or something like that.