At any rate, that isn't really what I was asking. My interest is much more mundane. What have all the wind turbines and solar farms done to daily max and min voltages and outage rates?
I stopped working for Ontario Hydro a long time ago in mid 90's so I'm not plugged in anymore, from what apI have read, delta V would be within the normal range and outage rates would be impacted more by reduced power system maintenance than the additional generation. The latest inverter based generators will help with many aspects; system stability, voltage dips, efficiency and outages, they can actually operate as an island and help restore the grid when it is taken down, so in short more good than bad.
Your friends comments about NUG make complete sense. The Wikipidia explanation appears to be accurate. I can say that I lived in Manitoba for about 20 years and their power system is lower cost and more reliable, however they are blessed with lots of hydro. IMO Ontario would be better off purchasing power from our two Canadian neighbours than their latest plan.
I've not been able to mill out something that has a friction fit over the square part of the knee shaft. Likely because it's not really cut to a fine tolerance not to mention slightly raised marks from set screws.
So instead of using under size brass screws as pins I thought I'd turn a steel one on the lathe. The bevel is so it follows the 1" ID of the round part of the pulley bore.
It seems to be working better than the brass one. I've only made one and used the two screws, one to press it down on the shaft and one to lock the first. I think it's twisted the pulley slightly so one on the other side would probably be better but that means trying to create a completely symmetrical hole.
I have some other ideas too. Perhaps just a spacer on the other side.
So a while back I was changing the power draw bar over to a stepper motor and planetary reduction drive. I decided to add an encoder to the motor so I can detect how many turns and when it's unable to tighten any further. The goal is to be able to set the current into the motor for tightening at a lower value than for loosening. So I should always be able to loosen the draw bar.
Trouble is the stepper motor I had does not have mounting screws on the back for an encoder and I didn't want to take the chance on pulling it apart and destroying it or drilling/tapping into the back and damaging it. The back shaft is very short. No room for a thick mounting plate so I made a thin one. Here's the result.
The four little 3mm screws just fit nicely into the left over thread on the back side of the motor cover. The two encoder mounting screw holes were counter sunk from the back side and two 4-40 flat head screws with most of the bevel turned off were epoxied into place serving as mounting studs.
So how did I make it?
Obviously CAD/CAM first. AlibreCAD and then AlibreCAM (MecSoft CAM).
Once the holes were drilled I ran a 1/4" bolt down the middle into a T-Nut and a couple of self tapping 3mm screws to keep it from turning.
Then mill the outside profile and clean up the holes and about 0.019" per pass for depth of cut. Speed 18 IPM at about 2600 RPM with a 1/4" two flute end mill.
Now to whip up some sort of connection to the encoder and write the software to track that it's moving and how far it's moved.
I can't yet test the motor mounted to the planetary drive because the CUI encoder uses a connector that I don't have. Or if I did I don't know where it went. So I used the second mounting plate to put one of my US Digital Encoders (250 lines per rev) onto the back of the other stepper motor. Made up a cable to replace the panel mount encoder into the dsPIC33 test set.
I did actually start writing the software for the dsPIC33 to also send out step/dir pulses and then decided to do it that that was way too much work. Instead grabbed the ELS from my Gingery Lathe and wired it up to my external power supply and Bergerda stepper driver.
What a hodgepodge of wires.
I reprogrammed the ELS with the debug messages enabled so I could see what it was sending out. Then configured it for 50 passes 1" long and told it to run. After 53 passes (50 plus 3 spring passes) the mark on the stepper motor, after move back to 0.000 lined up perfectly as did the encoder position which started at -1. (the second position line is motor degrees).
After all that I then sent it to do a single pass and stopped it at the end. Main (S3) Show Encoder
Velocity: 0
Position: -10001
Position: -2250.2
So what does it mean?
It's a 10 TPI lead screw in the configuration. That means 1 turn of the lead screw for each 0.1" and that means one turn of the motor shaft is 0.1" Since it's 250 lines on the encoder the quadrature mode means 1000 pulses per rev and to move 10 revolutions is therefore 10,000 pulses. The motor driver is set up for 1600 steps per rev as is the ELS.
Oh and here's a bit of the diagnostics. The ELS is running in Broach mode so the spindle doesn't need to turn. It's just doing 50 passes of 0.001" per pass with a thread depth of 0.050. The tool bit is programmed to follow the standard 29.5 degrees along the thread flank. It does this by shifting over a bit on each pass as it goes deeper on each pass.
Here's the diagnostics for the last pass. Move: TO_END
Move: AT_END
Move: WAIT_END_OUT
Move: WAIT_END
X= 0.0500, Z= 0.0283
ZS=453, ZE=16000, XS=-2400, XR4800
Return To Start ... Move: WAIT_TO_START
The X depth at the end was 0.050 which is correct. The Z End position is 16000 which is 10 turns of 1600 steps per turn.
The Z starting position was originally 0 but has moved to the left by 453 steps or 0.0283". And if we do arctan(z/x) we get arctan(0.0283/0.050) = 29.5 degrees. So that matches the ELS parameter for thread angle.
I had to press the ALT-Z_HOME button on the ELS to move it back to the original BEGIN position. And the encoder counter reported -1. Exactly where it started.
This encoder caused a lot of issues on the DC servo motors which is why I switched to CUI encoders. But even with single ended outputs mechanically on the end of the stepper motor it appears to be working quite well.
BTW, just to add some info. Why if I've made a prototype of a 32 bit PIC32 interface to the original ELS did I use a 16 bit dsPIC33 for testing the encoder software?
Well the Automotive Networking Board on the left side of the photo has a PIC32MX795 PIM module. That PIC processor has Ethernet and USB capabilities but does not have quadrature encoder hardware. So it was easy enough to port the 8 bit ELS software over to it and discover it was running more than 10x as fast but I didn't want to do a software quadrature encoder. I'm already doing that for the MPG knob on the ELS.
And it does work: Project ELS_PIC32 ANB Revision 0.10b
E_ : EEROM Operations
f : Show Control Flags
t : track Spindle SpinRate value
s : show system states and flags
m : Dump menu list
v : ELS PIC32 Version
?Hh : This Help Menu>
So way back when I was working on this project I ordered four PIC32MK1024MCM064 processors with 1MB flash memory. The processors are only $14 and are expected to be in stock again in September. Luckily I have 4. A while ago it was more than a year to get more which is why I put the project on hold.
So I think I'm at the point where I can now finally get around to laying out the PC Board for the PIC18 CPU replacement.
If anyone is interested here's the latest schematic for the adapter. It will likely be a 4 layer PC board with some extra I/O. And since I had a few extra pins I've brought a Y axis out to the DB-25. And there are jumpers to reroute a couple of pins so that the Chinese Break Out Board can connect directly.
If I've done it right then this can become the Draw Bar and tool changing Controller. Buttons to release and load TTS or R8 Tools (2 revolutions or 18). Communications with LinuxCNC is via CAN bus. Depending on what I end up using for a tool carousel if there isn't enough I/O the CAN bus can expand extra I/O. But I can have a load tool button and select which tool number.
Finally because I've added the Y axis this version could also become an ELS for a mill. With simple power feed from a BEGIN to END position. Etc. Depends how fast I finish the other 42 projects in front of that.
CUI encoder now mounted. Yikes. Way more sensitive to electrical noise.
Since the encoder has differential outputs it's clear that I should add a set of receivers as close as possible to micro-controller. The CUI manual does say to connect the shield wire directly to the motor. It was still a bit flaky. A clip lead from that point to the heatsink (ground) of the ELS and it suddenly became very solid.
Why the difference between the CUI and the US Digital with the same type of motor?
Well the CUI is a capacitive encoder that has a processor that creates the resolution programmed in via a serial port and PC application and creates the quadrature outputs. It's possible without good grounding and shielding that it's more sensitive.
The US Digital (with this version having its own bad rep) is optical with 250 lines on the disk so the two optical sensors create the quadrature outputs. So there's no indeterminate values based on noise or load. More absolute.
Think I might connect a socket and torque wrench to it and see when step pulses stop increasing the encoder. I can just keep increasing the torque wrench settings and stepping until it no longer goes click. See if the motor will really create 20 ft-lb.
Alright. Just had to try this.
Static torque with no motor motion and at 240 in-lbs (20 ft-lbs)the torque wrench easily clicks and the motor doesn't move.
Then jog slowly applying torque to the wrench and it also clicks.
When I apply 240 in-lbs to the actual draw bar with this torque wrench it's tighter than I normally do by hand with a wrench.
I think a fast move turning the drawbar until the motor locks up as indicated by the encoder. Stop and restart then turning slowly until it locks up again and it will be at whatever torque the current through the motor windings are set to.
To release, just increase the current to the full 3A, and turn counter clockwise for two turns for TTS holders. If the draw bar is captured correctly it will push the R8 collet down and the TTS holder will just fall out.
