Super-PID new low-cost router speed controller

[CarveOne]

I sure hope you guys have all of this figured out by mid January when I plan to order a G540 for my smaller machine.

You're making my head hurt trying to keep up with this wiring stuff.

CarveOne

[ger21]

I did find that changing these values, particularly the min spindle rpm is not always immediately recognized by Mach3.

A lot of changes in Mach3 require a restart to take effect.

[ger21]

Hmmm, Gerry, I didn't know the limit switches can share an input pin. If that's the case, I can free one input pin by sharing X & Y axis. Is this possible with a G540? I hope Thoug will explain since he use the G540. The way I understand it, the "tach" output will connect to input 1 on the G540, inputs 2=X, pin 3 share Y-Z axis.. Is this right?

I don't have a G540, so can't help you there. You can connect all your limit switches to a single pin if you'd like. Home switches are a little different. If you connect them all to one pin, then you can only home one axis at a time. If you have a gantry with separate home switches, they need to have their own pins.

[lancut]

"Home switches are a little different. If you connect them all to one pin, then you can only home one axis at a time. If you have a gantry with separate home switches, they need to have their own pins."

OK, that answers for me. I have 3 inputs and all of them used for homing...

[ger21]

f you have a gantry with separate home switches, they need to have their own pins."

I should clarify that. Say you have X, Y, Z, and A slaved to X. You can have the X, Y, and Z on one pin, and the A on another.
The you'd home, Z, then Y, then X and A together.

Right now I have Y and Z on one pin, and X and A on their own.

[jsantos]

I don't have a G540, so can't help you there. You can connect all your limit switches to a single pin if you'd like. Home switches are a little different. If you connect them all to one pin, then you can only home one axis at a time. If you have a gantry with separate home switches, they need to have their own pins.

I've got 4 home switches and I've got my A-, Y-, and Z- home switches connected to one input line on the G540. My X is on a separate line. The only reason I have X on a separate line is 'cuz I use the auto-squaring feature of Mach 3 and it doesn't seem to like having the A- and X- axis on the same line.

You're right, though, that they home one axis at a time. That hasn't been a problem for me.

[lancut]

Gerry, I appreciate the detail explanation. The more I think about it, I will use the input pin used by Z axis and connect the "Tach "output. I keep the X & Y homing positions connected for obvious reasons. I really don't need to home Z.

[ger21]

Just connect the Y and Z homes switches to the same pin.

[lancut]

Will Mach3 allow that, or do I need to take special steps to do this?

[ger21]

Yes, it will. It's how mine is set up.

[lancut]

OK. Thanks.

[adam_m]

I sure hope you guys have all of this figured out by mid January when I plan to order a G540 for my smaller machine.

You're making my head hurt trying to keep up with this wiring stuff.

CarveOne

Amen!

[Arbo]

I thought Mach always homed one at a time, as the 'home all' is generally a script that does one axis at a time. In which case all home switches on one line is, as you say, ok.

What is the auto-squaring feature?

[Arbo]

I sure hope you guys have all of this figured out by mid January when I plan to order a G540 for my smaller machine.

You're making my head hurt trying to keep up with this wiring stuff.

CarveOne

Never fear, I plan to order mine on monday, which will let it be in transit while away on vacation, and be here not long after I get home. So I plan to work on getting it all up and running before you order yours.

BTW, does anyone have a dxf of what they cut out for a box for this unit? And what material they used?

[ger21]

I thought Mach always homed one at a time, as the 'home all' is generally a script that does one axis at a time. In which case all home switches on one line is, as you say, ok.

What is the auto-squaring feature?

You can edit the script to home in any order you want, and any combination of axis suimultaneously.

When you have a gantry driven by slaved motors, Mach3 can home each side of the gantry to a separate home switch. Set up the switches so the gantry is square when homed, and if it gets out of square at any time, homing it will re-square it up.

[ger21]

It took me about 4 hours, but I've got V1.5 running from the parallel port through the circuit Roman posted.

Here's the actual rpm's vs commanded. Commanded speed first. Pulley set from 0-30100rpm. Rpm's are ±5-10 or so

5K=5000
6K=5950
7K=7040
8K=8005
9K=8975
10K=10060
11K=11020
12K=12000
13K=12950
14K=14040
15K=15000
16K=15970
17K=17050
18K=18025
19K=18970
20K=20060
21K=21030
22K=22000
23K=23080
24K=24060
25K=25000
26K=25960
27K=26375 (It's a 27,000 rpm router)

So it looks like ±50-60 rpm for the most part. It does take about 5 seconds or so to settle at the commanded rpm.

Todd, do the PWM settings have any effect? What is your base and minimum set at? Also, do you know, does the motor tuning effect the accel at all?

One strange thing, is that with a spindle delay, it starts dropping to 5000 during the delay amount, then shuts off. Without the PWM connection, it would shut off immediately, and wait for the delay before moving. Maybe it's dropping the rpm to 0, but the SuperPID is keeping it at 5K. I guess I'll turn the delay off.

Adding the little circuit has finally reached the limit of the 150w power supply running my entire machine. The two big fans in my case stopped, so I had to unplug them. tomorrow I'll try it with just 1.

[RomanLini]

Thoug-

Yeah, I was originally thinking the pulley ratio would scale the PWM output. But you are correct, you need to use the spindle min and max rpm settings. I was able to bring the top end into alignment by setting the max spindle rpm to 30250 instead of 30000. I was also able to align the bottom end by setting the min rpm to 350 instead of 0. This seemed to provide a very nice match across the full rpm range. I did find that changing these values, particularly the min spindle rpm is not always immediately recognized by Mach3. It seems to require you to set a new spindle rpm before it checks the settings and calculates a new PWM setting.

That's good to know, thank you! It's possible that Mach3 only calculates and sends the new PWM signal AFTER you have made a change to the spindle RPM. So people calibrating their Mach3 manually need to be aware of that.

It's also good to hear you could "tweak" those 2 min and max settings in Mach3 and get the calibration nice and accurate just doing it mnaually.

Lancut- The "TACH" output of the SuperPID is a logic-level 0v-5v signal (designed to drive a parallel port or a break out board or test instrumentation), and it is not directly compatible with the G540 inputs. This issue is under revision for the SuperPID PCB re-design next year.

I may have a simple G540 solution for you soon, but I need check something first with Mariss.

Ger21- Re re-starting Mach3 to get the new spindle seetings to work; The Mach3 manual does not indicate that the program needs to be restarted for spindle settings. I think Thoug hit the nail on the head that Mach3 only calculates the new PWM each time you change the spindle RPM itself. This makes sense, there's no need for it to change the PWM unless the spindle RPM has been commanded to change.

Arbo- There are a couple of .DXF files for people's home made SuperPID boxes, they are on pages 3 and 4 of this thread I believe. I need to start making that thread index!

Ger21- 4 hours so solder up all the parts in that circuit and wire it all up and test it? That's not bad, for someone who said they haven't done much electronics before you've come a long way.

Thanks a lot for taking the time to record all the Mach3 RPM results! I have added percentage error values to your figures (see below)

Ger21 Mach3 + SuperPID v1.5 RPM test results with Mach3 set to 0-30100;

Set Actual Error%
5K = 5000 = 0
6K = 5950 = -0.6%
7K = 7040 = 0.6%
8K = 8005 = 0.1%
9K = 8975 = -0.3%
10K = 10060 = 0.6%
11K = 11020 = 0.2%
12K = 12000 = 0
13K = 12950 = -0.4%
14K = 14040 = 0.3%
15K = 15000 = 0
16K = 15970 = -0.2%
17K = 17050 = 0.3%
18K = 18025 = 0.1%
19K = 18970 = -0.1%
20K = 20060 = 0.3%
21K = 21030 = 0.1%
22K = 22000 = 0
23K = 23080 = 0.3%
24K = 24060 = 0.2%
25K = 25000 = 0
26K = 25960 = -0.1%
27K = 26375 = -2.3% (special error; It's a 27,000 rpm limit router)

As you were able to get the error in every range well below +/-1% this looks like a fully linear result, ie as good as it gets. It's hard to read the SuperPID tacho to better than 0.5% as the last 2 digits do tend to change a bit during normal PID operation.

One strange thing, is that with a spindle delay, it starts dropping to 5000 during the delay amount, then shuts off. Without the PWM connection, it would shut off immediately, and wait for the delay before moving. Maybe it's dropping the rpm to 0, but the SuperPID is keeping it at 5K. I guess I'll turn the delay off.

That looks like Mach3 is first dropping the PWM down to zero, then the delay, then turning the spindle off. That may be beneficial with 3-phase VFD spindles as it lets them spin down but has no benefit with a SuperPID and router. I think you are right it's best just to turn that delay off.

Adding the little circuit has finally reached the limit of the 150w power supply running my entire machine. The two big fans in my case stopped, so I had to unplug them. tomorrow I'll try it with just 1.

The little filter circuit uses only a microscopic amount of current, so I think your fan symptom was much more likely caused by disturbing the fan wires or plugs rather than by a power usage increase.

Anyway it's great to see some fully automatic SuperPIDs running!

[mmcp42]

I've been fascinated by this thread - lost many hours over the last couple of days trying to absorb it all

Some good stuf (and some good peeps) on here

my 2p for Roman -

Is it possible to arrange for software updates to be downloadable and the chip upgraded from a PC?

I can't see the MCU chip type, but things like Arduino use the AtMega series and are dead easy to upload new software

[/2p]

[ger21]

Adding the little circuit has finally reached the limit of the 150w power supply running my entire machine. The two big fans in my case stopped, so I had to unplug them. tomorrow I'll try it with just 1.

The little filter circuit uses only a microscopic amount of current, so I think your fan symptom was much more likely caused by disturbing the fan wires or plugs rather than by a power usage increase.

Could it be that I has wired it wrong the first time I tried it?
First time I had a bad solder joint connecting pins 2 and 3? (or 3 and 4, going by memory) Then when it still didn't work, I realized I forgot to connect the pin on the chip that feeds into the resistors.

It only took an hour to make the board. Another hour was trying to figure out how to run the wires, then 2 hours troubleshooting my mistakes.

The power supply was already on the edge of being overloaded, though. It's running two big, high powered fans that came out of an old rackmount case I used to use. And it's always had some stability issues that I'd always suspected were caused be the power supply.


One question. I didn't have a spare wire to run a ground from the filter to PG on the SuperPIDm so I just connected it to the Ground terminal on the Super PID. It works, and I'm assuming it's fine, since all the grounds come from the PC power supply, and are the same??

Big thanks for all you've done for the community. The addition of the Super-PID and electronic home switches have greatly increased the machine's ease of use. And not needing a breakout board is a nice bonus. All my electronics are plugged directly into my parallel port.

Now I just need to cover the pot hole in my Super-PID case cover..........

[lancut]

"Lancut- The "TACH" output of the SuperPID is a logic-level 0v-5v signal (designed to drive a parallel port or a break out board or test instrumentation), and it is not directly compatible with the G540 inputs. This issue is under revision for the SuperPID PCB re-design next year.

I may have a simple G540 solution for you soon, but I need check something first with Mariss."

Roman, I appreciate your effort, but it's not really a "Big Deal" to me. I can use it either way, and is fine by me...