I see from your last post you are talking in your sleep again???:rolleyes:

I've been wondering if it wouldn't be better to use different connectors on the Gecko G20x stepper drivers. As configured from the factory, the headers are four sets of three; however, using a 2-4-4-2 configuration would match the functions better. For instance, positions 1-2 are for power in, positions 3-6 are outputs to the motor's coils, positions 7-10 are inputs (step/direction/common/disable), and positions 11-12 are for the current limiting resistor.

If the headers were of the 2-4-4-2 type, then all of the motor's connections would be on one 4-terminal connector, which would allow easy connection without excessive wiring/rewiring.

I normally use an eight-position + chassis ground terminal block for my 6-wire motors. Positions 1-6 are for the six conductors to the motor. Positions 7-8 are for the current limiting resistor and chassis ground is for the shield/drain surrounding the conductors going to the motor's coils. By doing that, I can standardize all 6-wire wiring regardless of which motor I'm using.

you are correct. Earlier versions had one connector. but, alas, soemtimes it is cheaper to get all of one type, even if that type does not match the needs exactly.

My 201a Gecko's have a single fixed block, does not come out. but these are from the very first run. Revision A drivers.

Dave

Thanks Gerald/Driller/Mike. I knew there was a good reason. Engineers never do anything on a whim. I'll wire mine directly to the Geckos and I'll use the terminal block tip from Mike.

If you do change the terminal blocks, make sure you get a good quality. Gecko did have a bad experience with a supplier just over a year ago and were obliged to find a better quality. "Bad quality" connectors loose their grip on the header pins if disconnected too often. In general, this style of connector is not designed for daily/regular use. The "poor quality" that Gecko had before would survive maybe 5 to 20 disconnections only - I guess the better quality one will go into the hundreds . . . . . ?

I've ruled out using the 2-4-4-2 connectors on my Geckos. I really like the idea but every time I pulled the current connectors off and then replaced them, I was scared me to death that I'd break one. If I had your electonics experience, I probably wouldn't be so worried but I'm a newby at this stuff.

Doug,
The 2-4-4-2 connectors were just an idea. So far, I haven't been able to find any. It seems that the only choice is 2-circuit and 3-circuit connectors.

I think that I may have given the wrong idea on why I would use them (if I could find them). I like to mount heavy stuff like the transformer, caps, stepper drivers, etc. and then wire everything together. Sometimes, there just isn't enough room to easily wire things together after installing major components; so, that's why I like removable connectors. Once they're properly wired and installed, they would stay installed for the life of the component. I don't think that even the new black headers are designed to be installed/removed more than just a very few times without loosing their integrity.

Gecko's 6-6 terminal blocks are actually 3-3-3-3. There are tiny dovetails between the blocks. Gecko uses a knife or chisel to cut off the center dovetails and make 6-6. You can use 2's (or 3's) and dovetail them together as you wish - just cut off the dovetails where you want seperation.

Gerald/Mike/Anyone,

I want to mark my wires and terminals so tonight I bought a set of stickers designed for such a purpose at Home Depot. I plan to stick them on and then cover each one with clear heat shrink. My question is this: is there some type of numbering or lettering convention I should follow? Do I letter the terminals and number the wires and then use a reference sheet to record it all? Do I give the wire the same number or letter as the terminal it connects to? I don't want someone looking inside my box and instantly knowing that I'm a moron. :D

Doug, I havn't come across the "wrong" way to mark wires. Somebody else's numbers are mostly considered to be understood only by them. I would say design your own system.

Doug, I agree with Gerald. As long as you make an accurate chart, any marking scheme that you decide to use will be valuable. If possible, look at the documentation that Kodak or IBM provides to their customers. In a typical binder you'll find a theory of operation, flow charts, complete schematics for each device in the machine, wiring tables, and a trouble-shooting guide. The more documentation that you can provide now, the easier it will be to diagnose a problem sometime in the future.

Terminal Blocks - for a guy not use to using these things and now having some understanding of what they do, can you (Gerald or Mike) suggest a model and source for these things that will give me long term use.

Nils, I think the rest of the guys have more recently bought them. I have never seen poor quality ones, but then again I sit on another continent. :)

Over the years, I've used whatever brands that I could buy locally. They have all been good quality. The only drawback of mixing brands is that each brand seems to have a snap-together feature that doesn't match the snap-together feature of another brand.

I just checked the offerings at www.automationdirect.com. They have the DN-T12 terminal block (Euro 2.5) for wire up to 12 gauge and the DN-T10 terminal block (Euro 4) for wire up to 10 guage. (I use the Euro 4 size because my favorite terminal block screwdriver fits the screw heads better.) In addition to the terminal block, you'll need to order some endbrackets similar to the DN-EB35, some endcaps similar to the DN-EC1210 and some rail similar to DN-R35S1. Also, think about buying some jumper bars and some pre-printed labels or tags. The jumper bars allow you to more easily connect a series of terminal blocks together. The labels or tags makes it easier to document each terminal block.

You may be able to find terminal blocks locally. Even though the blocks that I buy locally cost about two times more than the blocks from FactoryMation or AutomationDirect, I can buy just the quantities that I need instead of being forced to buy full boxes.

Gerald...
I have been looking at your photos above and on post #2, you mentioned that:

3. The empty terminals further right are for the shielded cables to the E-stops, Z-zero, etc. All Inputs. The shields also have terminals dedicated to them.

I cannot see where any of the shields (braided?) are connected in your pictures... or just how they are connected. Is there a specific "braid" connector made for these situations or is it similar to an AV cable in which the braids are picked up and grounded on a terminal itself? My thought... slice the braid back from the cable, twist it and crimp a connector to it... seemed amateurish (which, incidentally, I am attempting to work my way UP to)...:D

Thanks... as always... for your help
Bill McGuire

This is the only pic I can find now:


Yes, I do crimp a lug onto the braid. In the pic above the wire is thin and the lug is massive in comparison.

I don't unravel the braid to get the wires out - I actually pull the wires through the side of the braid "tube" leaving the braid pattern intact. This is easier than it sounds..... Bend the stripped end of the cable over like a hairpin, then pick the wires out of the top of the kink. Must find another photo . . . . .

Thanks Gerald...
You explained it very well. I just wish I'd taken up miniature jewelry work back when my fingers were still coordinated with my brain... it'd probably make my life easier when I get to this phase...:D

G' what the AMPS on the contactor? I was planning for 32Amps which will include the power to VFD, is it wrong to feed the VFD from the contactor?

RGDS
Irfan

G' my mistake again :( I looked over the drawings and its clear now that the VFD can be connected thru the contactor.

Irfan, the issue here is: How can we stop the spindle with the E-stop?

That is the reason the VFD is powered from the main (E-stopped) contactor.

G I was assuming that since I will be using a spindle control card, the E stop would pulse from mach and stop the spindle.

Thus I can use a lower amp'd contactor and save some cash,

however i will go the regular way and power the vfd from the contactor - just to be double sure.

RGDS
Irfan

Also then, a false pulse (error pulse) from Mach could also start the spindle by mistake . . . . .

You cannot trust Mach to have the final decision on whether the spindle runs or not. The spindle is probably the most dangerous part of your machine.

Yes Sir, I am surely going your way :)

Mounting of G203V
 

Hi all, is it big problem to mout G203V on the same metal plate as the rest of components in control box (see picture) ? As i can see almost all of you mount them on separate alu plate. Thaks Tomas

Tom,
The reason for mounting separate is not a physical space issue, but a thermal issue. The separate plate allows for the drives to heatsink and cool. The additional plate allows for better area contact from surrounding air, thus cooling the devices.

The Gecko's run fairly cool, so you may be okay.

I reread g203v manual and it doesn't have specific heatsink requirements, but cooler is better.

Sean

BTW, nice transformer....did you make that yourself?

Sean, thanks for reply. I made top of transformer today morning. I plug it in and measure 33,7 VDC on capacitors. I expected 35VDC and I am not sure if it is enough for my Oriental Motors.
Have a nice day
Tom

did you check your main supply voltage? it is perfectly acceptable to have a +/-10% fluctuation.
In real life, nothing is smack on... especially in engineering stuff...

33,7 ( you should be fine ) :)

Hi all.

I am planing the join of this alu pieces for building the drivers heat sink.

They are 2 mm thick

Any coments ???

Not sure how that will make a proper heatsink.

I agree. Through, real heat dissipators are realy cheap.

Ok, in next days il make a test and feed back

If you don't weld them, you must fix them tight and use some heat conductor fluid,
like those used in computer CPU/fan mount.
But I still believe the "wings" are not thin and long enough to produce the expected result.

Modern drives have very little wasted heat. The stories about big heatsinks for drives come from 10 years ago.

Hi all.

After reading and reading, I have not found information about

the drivers fan specs and its wiring diagram.

Can someone help me with this and a suggested fan model.

Thanks

See:
first posts on MechMate DIY Control box full spec screened spindle 3phase

and

Cooling fans

For a cooling system that works. It has no fins on the heatsink. The drives are cool all the time.

Ok, now i am clear about heat sink and fan

Thanks Heath, Axel and Gerald.

Hope see all you in next questions.

VFD mount
 

Hello !

I am planning to build my control box.

I would like to know if I can put the VFD inside or is it better to put it in a separate box ?

Also, I am looking for a VFD and can you tell me what "HP" means in VFD specifications.


Thank you !


Hardouin

I think it is better to put the VFD outside the controller box. Keep the line noise that the VFD and Spindle wire is generating away from the controller box.

Outside if you can. It just takes one more noisy thing away from the others.