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  #31  
Old Mon 08 December 2008, 23:18
kn6398
Just call me: Kray
 
Fort Worth
United States of America
Yes, she is a beauty also very big
taken up half of my garage.
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  #32  
Old Tue 16 December 2008, 21:40
kn6398
Just call me: Kray
 
Fort Worth
United States of America
Power Supplies

OK I got most of my power supplies components. According to the spreadsheet attached, calculation using motor PK296A2A-SG7.2 wiring half-coil I need a 27.71 VAC transformer and 24,495uf capacitor. I got a 30VAC transformer and 680,000uf capacitor instead. I know an oversize capacitor is OK but this one is double the reqired size. Its BIG Will this be OK or sholud I find a smaller value capacitor? And another thing the guy at the electronic store insisted that I use an external fuse at least 3A for the transformer. Is that right?? That sound kinda low.
Attached Images
File Type: jpg pic 022.jpg (162.2 KB, 566 views)
File Type: jpg pic 023.jpg (179.4 KB, 565 views)
File Type: jpg pic 024.jpg (175.4 KB, 564 views)
File Type: jpg pic 025.jpg (146.9 KB, 559 views)
File Type: jpg pic 026.jpg (156.5 KB, 558 views)
File Type: jpg pic 027.jpg (158.5 KB, 548 views)
Attached Files
File Type: zip power supply cal.zip (17.6 KB, 40 views)
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  #33  
Old Tue 16 December 2008, 22:51
Gerald D
Just call me: Gerald (retired)
 
Cape Town
South Africa
That capacitor is an overkill. While the theory says it is going to do a brilliant job of smoothing out the ripples, I wouldn't want that thing in my control box. . . .
- takes long to charge up: might blow the transformer fuse on switch on.
- takes long to discharge: might burn some wires if you are fiddling around there.
- makes a huge bang (and mess) if you wire it wrong.

A capacitor can also be very big if it is rated for a too lowhigh voltage. You need to be getting a capacitor rated about 10% above the DC voltage you plan to use.

One fan is more than enough.
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  #34  
Old Wed 17 December 2008, 13:15
domino11
Just call me: Heath
 
Cornwall, Ontario
Canada
Quote:
Originally Posted by kn6398 View Post
I need a 27.71 VAC transformer and 24,495uf capacitor. I got a 30VAC transformer and 680,000uf capacitor instead. I know an oversize capacitor is OK but this one is double the reqired size.
Kray,
680,000 uF is 28 times larger! I think from the size in the picture that the capacitor you are using is probably a 68,000 uF? If that is the case I would not worry about using it. The 680,000 would be a welder as Gerald states if you made a mistake! Check that value again. Also as Gerald states make sure that the voltage is at Least 10% or more higher. Higher voltage is not a problem.
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  #35  
Old Wed 17 December 2008, 19:00
kn6398
Just call me: Kray
 
Fort Worth
United States of America
OK I added to many zero it 68,000 uF not 680,000 uF and it rated at 75V.
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  #36  
Old Wed 17 December 2008, 21:35
domino11
Just call me: Heath
 
Cornwall, Ontario
Canada
Kray,
I would not worry about using that capacitor at all. You will have about 43 volts DC on it after rectification, and it should filter that supply nicely.
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  #37  
Old Wed 17 December 2008, 22:24
Gerald D
Just call me: Gerald (retired)
 
Cape Town
South Africa
On paper, that capacitor is okay. I am just not used to seeing them bigger than the transformer!
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  #38  
Old Thu 18 December 2008, 08:35
domino11
Just call me: Heath
 
Cornwall, Ontario
Canada
Gerald,
The working voltage being 75V DC makes for a larger capacitor also, if it were a 50V capacitor it would be at least 33 per cent smaller. Also higher grade capacitors and higher temp rated capacitors are usually larger as well. I have worked with capacitor banks over 1F at 160VDC. That really makes a spark when you slip with a wrench, one guy at my work know for sure!
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  #39  
Old Thu 18 December 2008, 09:12
Gerald D
Just call me: Gerald (retired)
 
Cape Town
South Africa
There is one thing worse than capacitor banks. . . . battery banks. . . . . as found in the bottom of submarines . . . exactly the place where things like to fall. . . and get vaporised. The other thing I remember of those huge DC currents is that screening the cables helps nought. A main battery cable running past a TV screen would suck the picture right off the edge. Hey, we are messing up Kray's thread.
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  #40  
Old Thu 18 December 2008, 11:19
kn6398
Just call me: Kray
 
Fort Worth
United States of America
OK, it good to know I can use the capacitor. The problem with going into those surplus stores is you can't get exactly what you want. The value will neither be too small or too big. About the fan I couldn't resist 50% on the second one since I already drilled the holes I mine well use it. I'm not really gaining any free space if I take one out.
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  #41  
Old Wed 04 March 2009, 01:57
kn6398
Just call me: Kray
 
Fort Worth
United States of America
Back to finish my build


OK, it been awhile I haven't posted any update. But to continue on where I left off, the enclosure I bought from EBAY never went through. Someone stole it from their ware house so I never gotten the box but I did get my refund back though. I went to Lowes and bought one, BIG mistake it was not deep enough.



Went back to EBAY and got me the proper enclosure 20x24x8. This one was big and had plenty of room. I got it wired up to test the motors and E-STOP. Here is short clip showing the motors spinning and verifying the E-STOP work. Notice that when I press the E-stop the PMDX still has power that because I connected to the wall outlet just for testing purpose.

I attached the schematic if anyone see anything odd please let me know. The schematic is basically the same as Gerald's plan.



I also got the table painted and wired just need to finish mounting the control panel to the wall and I should be ready to cut in a couple of days.
Attached Files
File Type: pdf schematicv1.pdf (310.6 KB, 64 views)
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  #42  
Old Wed 04 March 2009, 02:36
Gerald D
Just call me: Gerald (retired)
 
Cape Town
South Africa
Gee Kray, we last saw you a week before Xmas and look what you have done since! Well done!
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  #43  
Old Wed 04 March 2009, 02:50
javeria
Just call me: Irfan #33
 
Bangalore
India
wow - thats a surprise

hmm when will I finish mine

Kray is that a bit darker blue - or am I color blind.
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  #44  
Old Wed 04 March 2009, 03:24
Gerald D
Just call me: Gerald (retired)
 
Cape Town
South Africa
That is ShopBot's "Cobalt" blue!
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  #45  
Old Wed 04 March 2009, 18:46
kn6398
Just call me: Kray
 
Fort Worth
United States of America
Yep, it call deep blue. I got it at Oreilly auto part they had only one kind of blue and they don't mix paint to your choice.
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  #46  
Old Wed 04 March 2009, 18:47
kn6398
Just call me: Kray
 
Fort Worth
United States of America
It does look like the shopbot blue, sorry didn't pay attention to the color..
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  #47  
Old Wed 04 March 2009, 19:15
kn6398
Just call me: Kray
 
Fort Worth
United States of America
Control enclosure compledted!!!

The control box is completed and it move!!!

mech053.jpg
mech058.jpg
mech059.jpg
mech060.jpg

I'm waiting for my router bracket from K2 CNC and some bits from Mcaster. I should be cutting by the end of the week.

I hooked up my SSR to pin 14 on thd PMDX to turn on the router and set it in MACH3 as output. So do I have to write some kind of macro to tell Mach3 to send a signal to activate the SSR?
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  #48  
Old Wed 04 March 2009, 19:38
kn6398
Just call me: Kray
 
Fort Worth
United States of America
I notice that all my description texts on the drawing for the gecko and the PMDX were missing. For some reason the solid yellow color on top hidden the text. Here is another copy with the missing text.
schematicv3.pdf
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  #49  
Old Wed 04 March 2009, 19:44
Gerald D
Just call me: Gerald (retired)
 
Cape Town
South Africa
Well done!

Connecting the SSR is discussed here:
Solid State Relay (SSR) for switching Router under control of Mach3

No macro needed. You put a an M3 or M4 command in your g-code file to turn the router on, and the M5 command to turn it off.

Obviously your Ports and Pins, Spindle Setup must be set up correctly for the relay on the correct port number.
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  #50  
Old Wed 04 March 2009, 19:53
Gerald D
Just call me: Gerald (retired)
 
Cape Town
South Africa
Had a very quick look at your schematic;

- Your ssr is wired wrong. The "coil" and "contacts" are reversed with each other. The "contacts" need to be in the router's mains circuit.

- A 25amp fuse for the pushbuttons? that's too big!

- there could be more . . . . .
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  #51  
Old Wed 04 March 2009, 21:29
kn6398
Just call me: Kray
 
Fort Worth
United States of America
OK, I wired it right just how Mike described in the post I just drew it up wrong. The 25A fuse is for the AC line Black coming into the disconnect switch and the 3A is for the push button, again I drew it wrong but wired correctly. Revised schematic attached. OK, M3 and M4 to turn on and M5 to turn off got it.. Thanks
schematicv4.pdf
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  #52  
Old Wed 04 March 2009, 21:40
kn6398
Just call me: Kray
 
Fort Worth
United States of America
OK typo again it 14A on the AC line..
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  #53  
Old Wed 04 March 2009, 22:22
Gerald D
Just call me: Gerald (retired)
 
Cape Town
South Africa
1 amp is more than enough. 14 Amp will not protect the thin wires to the switches.
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