View Full Version : Close-up pictures of our wiring. . . . .

Tue 20 February 2007, 00:43

And then we need to get an umbilical from the gantry to the wall-mounted control box, still leaving a walking space to get around the table from all sides. Also, we need to get to a grounding/earthing point on the main table structure. We could have used "cable chain" but that is expensive for us. Our experience with a "hanging" loop has been good.

The upper conduit is the hanging/flexing/moving one. The lower section is just static across the floor (should have a cover plate over it).

If you go this route, the moving/flexing conduit must be split along its whole length - this allows it to twist as it flexes.....

reza forushani
Tue 20 February 2007, 03:25

Would you explain the buttons please. What type, what they do, where they are wired to?

Tue 20 February 2007, 03:44
There are 3 button boxes - one on the y-car, one at each end of the gantry. They duplicate each other (with one small exception). Reason for three duplicates is to save walking around the "beast" to find a button.

The red mushroom head is the E-Stop. It kills everything. Cuts all power. Used when blood or flames are near.

Yellow is the gentle stop, or pause. Stops the movement with a controlled deceleration. Used when the phone rings, you need to go to the bathroom, or you can see that you going to hit a clamp soon.

The green button (between the yellow and red-estop) is "resume". When you finish the phone call, get back from the bathroom, or have moved the clamp.

The button box on the y-car has a fourth (black)button. Havn't wired it in yet. It is intended to start a z-zero program after a cutter has been changed.

The buttons are wired to the PMDX-122 card, while the E-stop has a second set of contacts to the main power contactor.

All of the above functions can of course be done from the keyboard, but we may have unskilled labour who will be forbidden to touch the keyboard. We sometimes run for days without the need to get to the keyboard at all - operator loads sheet, presses green button, every 15 minutes. If lunch hooter intervenes, press yellow. If scared, press red.

reza forushani
Fri 23 February 2007, 03:50

Can you explain whether these switches are momentary or not (what type) and where they are wired to? The PMDX or Relay. How are you using your relay? Thanks again

Fri 23 February 2007, 04:02
Green, yellow, (and black) are momentary, push-to-make (Normally Open) switches. Let go, and they open again.

The Red, E-Stop, are actually two switches side by side, under one button. They are push-to-break (Normally Closed). When you have pushed the knob it mechanically "latches". To release the knob, you have to twist it, or pull it out. Only after the knob is released, will the switch contacts "make" again.

All the switches are wired to the PMDX - except the second switch under the E-stop knob which is wired to the main power relay. The main power relay is different to the router relay.

reza forushani
Fri 23 February 2007, 04:06
what relay do you suggest for the main power realy? thanks

Fri 23 February 2007, 04:21
An electro-mechanical relay (not SSR) or a form of a relay called a "contactor". You need to know if you are working 110V, 220V or 3-phase. Suggest you get your local electrician to advise you on this. Please believe me that I am out of my depth for specifying stuff for American power circuits. There is quite a difference in the way that your buildings are supplied. This relay is your "main switch" that has to switch off when blood starts flowing - don't trust a guy at the bottom end of Africa to pick it out for you.

Thu 18 October 2007, 10:14
Can anyone help?
There is a picture that shows up at the top once in a while that shows a 4 fuse power distribution block. I can't seem to find one anywhere. Does anybody have any suggestions?


Thu 18 October 2007, 10:34
If your referring to the block that Gerald uses to fuse his power supply to the Gecko's, then I have an answer for you!
Here in the US, I have found the only easy match, yet it's a 6 blade block.
- Advance AutoParts, ATV (Bussman part #15600 - 8 dollars
- Newark electronics charges 28 dollars for the same unit.

Good luck.

Thu 18 October 2007, 10:44
Thanks Sean!

Gerald D
Thu 18 October 2007, 11:11
If you are using Gecko 203's you can drop the external fuses - they have internal fuses. (Fuse type is not available in Cape Town - one of the reasons I am staying with the G202)

Tue 15 January 2008, 16:54

In the attached picture and in the picture of the bottom of you controller box there is a black cable tube with a metal connector used for the box and in this picture. I think it is metal. What is that called?

Gerald D
Tue 15 January 2008, 21:14
It is plastic, flexible pipe, common for looms (harnesses) in the auto and robot world. This one is by Igus.

Gerald D
Tue 15 January 2008, 23:13
The Igus "tube" catalog (http://igus.bdol.com/pdf/11-pma.pdf)

But now I think you are asking about the clamp at the ends of the tube. That is a standard pipe clamp (http://images.google.com/images?svnum=10&um=1&hl=en&safe=off&rls=IRFA%2CIRFA%3A2006-24%2CIRFA%3Aen&q=hydraulic+pipe+clamp&btnG=Search+Images) commonly used in the hydraulics world.

Sun 08 June 2008, 18:56
How are the buttons on the gantry boxes wired to the PMDX.???

Tue 10 June 2008, 13:10
the pause resume and estop loops from the gantry boxes that go to the PMDX are wired via the 7core wire and the pins that they are wired to are shown in the paper work that comes with the PMDX. It is pretty straightforward. If you have the PMDX paperwork and Geralds electrical plan from the downloads you should be able to find everything in those two documents.

Gerald D
Mon 21 July 2008, 03:13
Now that we are starting to order boxes and buttons for the next 5 machines, it is logical to increase the size of this box on the end of the gantry closest to the X-cable chain or umbilical:


This is very busy box with a lot of cable junctions. It is also the ideal place to locate the relays for the proximity switches.

The idea it to get a bigger plastic box and to drill the cover for the 3 buttons. It will function as a combined button, junction & relay box.

Thu 03 February 2011, 22:50
I notice the plug connections for the Motor wiring and I know various people have used other types of plugs.
Is there anything wrong with using wire connectors strips where each wire is held in place with a screw?

My reasoning is that the motors are unlikely to be removed unless there is a failure, so having a plus connector is unnecessary (except perhaps for shielding the connection?)

Thu 03 February 2011, 23:30
Red, those will work just fine. The plug connectors are just pretty. Really pretty, but doesn't matter in the grand scheme of things. Now, if motors failed on a regular basis, and folks had a dozen side by side machines with a repair parts stock, then the connectors would be more than pretty. But current reality is that motors don't fail, and once you assemble the machine, it just runs. In the very rare event you need to replace a motor or disassemble, the extra 3 minutes to break/make the four screw connections will be trivial.

However, you may want to pay attention to ensuring no dust finds it's way into the box in which you place those connectors.

Gerald D
Fri 04 February 2011, 00:17
Absolutely agree with Brad. Pluggable connectors are the root of most motor hassles.

Fri 04 February 2011, 07:46
Thank you for the quick reply. That sets my mind at rest and I can put the catalogue down. It was hurting my head trying to find suitable plugable connectors!

Another question, somewhat related. I notice in the pictures in post #1 that the cable chain support is bolted to the gantry tube. I can't find a plan detailing this. Is it necessary to use a clamp strip for this or can the thin beam walls support the weight?

Fri 04 February 2011, 11:04
You also get a better electrical connection with screw terminals than with connector pins.

Fri 04 February 2011, 12:53

I used those Red and they work fine. I just used silicone to mount them to the motors.