Thread: 6b4

Looking forward to have a good look over it Rod.
David

Thanks Harry and David,
It might be a bit boring showing so many shots of the machine trolley but my thoughts are this is something that doesn't get a lot of attention with the exception being Chris's build. My thinking is this is a very important part of the total machine and I spend as much time building the trolley as I do the machine.

You learn that by placing high voltage inputs and things like the VFD and air pump away from the lower voltages drivers and electronic signals that is saves you a lot of grief trouble shooting problems down the track. I still haven't mastered the routing of wires to make it look neat so I have another chance on this machine to improve on that.

I integrate the computer, screen and operater's control panel in the trolley so that it makes it easier to work the machine and dust problems with those components can be addressed. I've done a bit of work on the power supplies tonight so hopefully tomorrow night I will have something worthwhile to show.

Where do you get those linear slides, and bearings from? They seem quite a low profile.

They are THK 20's on the X axis and 15's on the y axis. I have a seller in USA that I have been dealing with for six years and he looks after me well. I buy any new rails of reasonable length he has even if I don't need them and stick them on the shelf. It is hard to get new rails at reasonable prices on ebay.

If they are over 1 metre the freight is too costly and you are better off with round supported rails from China for your dollar.

The square rails carry higher loads are more rigid and have radial support which the round rails don't have. The downside is there is less tolerance for error in the build.

thanks Rod

It was 39 degrees so not comfortable working today and tomorrow will be the same.

Got a bit done on the back of the machine including a couple of fans for air flow around the computer and two plugs for mains in. The VFD will have a separate supply to the computer and electronics.

I fitted two access doors that are sealed and instead of barrel bolts I have screws holding the doors shut so that little fingers can't get in there easily.

The power suppliers are mounted on an elevated aluminum plate so that there is some air flow around them. There is a 48 volt, 12 volt and 5 volt power supply and the 5 volt is elevated on legs again for cooling.

We'll see what tomorrow brings.

"6b4" - I thought that meant it was your 7th machine...

Cheers,
Andrew

Well past that figure now.

Originally Posted by arose62

"6b4" - I thought that meant it was your 7th machine...

Cheers,
Andrew

Damn, wish I'd thought of that. I TOLD him it was a pathetic sort of name.

Hi Bob,
It IS a pathetic sort of name

The last panel is done and the frame tapped but before it gets fixed it will be easier to do the electrics while there is full access.

Here is the power supplies rigged up and I have terminal blocks at the rear of the plate for the three DC voltages.

I try hard to keep it all neat and professional but I struggle with a vision of the finished job so for me it ends up like a plate of spaghetti.

The guys that do their electrics so neat have a real talent.

Perhaps somebody can help with this. I checked continuity between the main earth and the DC output voltage. There is no continuity between V minus and earth - I assume this is correct as it is the same with all three power supplies. Should I run a lead between earth and the V minus on the terminal block?

Originally Posted by rodm

Perhaps somebody can help with this. I checked continuity between the main earth and the DC output voltage. There is no continuity between V minus and earth - I assume this is correct as it is the same with all three power supplies. Should I run a lead between earth and the V minus on the terminal block?

thats correct , only cars have " negative earth " ( they dont have an earth )
if any voltage / amps go's to earth ( 50mA) it will trip a earth leakage switch ( if the wire it came from has an RCD)

i had a problem with my setup , the stepper driver needed a 5volt enable , with no 5 volt negative , it was using its 40volt as a negative , and i had to join the 40 volt psu and 5 volt psu negative terminals together ( you shouldnt have to )

the neutral wire is really a glorified earth , if you look at the power lines , there are 3 above ( 3 phase active ?10,00 volts ) , 4 below (240 volt) , the neutral go's to earth at the transformer ( if theres 5 wires the 5th is for street lighting ), the power station puts there neutral to earth

Thanks Ken,
It makes sense and it is the car wiring that I was thinking about.
Good to have you around and helping out.

Build slowed due to doing all the electrics while it was easier to access with the cover off.
First photo shows the VFD, Air Pump and power supplies all rigged up and last photo is the side fitted.
On with the console now then back to the machine build.