[MrFluffy]

Hi all, I am still working on my project sodick bf275 and test it, and I've got the computer side working and the table moving to mdi and pendant moves after much work inside but one last detail escapes me. How is the heavy power side of the cabinet hooked up to the machine workhead?
So far I have the inline fuses out to the output stage, but its time to put them in and test everything.

I have traced the heavy leads which I believe are called the discharge cables in correct terminology, out the power stage towards the table and you have 4 leads from the upper output rail labelled inside the cabinet P4N4->P4N1, with the leads labelled this end NR-4 to NR-1 coming from them, each led has a red and a black connector inside the cabinet, is the black connection cable shield to cut down on emi emitted and is it earthed out at the machine workhead end, the cabinet end or both?
The same wiring schema is repeated from the lower output rail (with the same duplicated cable names). Then finally two leads orginating from a contactor on the right labelled MA-1 and MA-2.

Not understanding how theye hook up at the table/machine stand area & how does the two leads off to the cabinet on the side of the machine workhead map to this. Of course my machine is missing all of its labelling at the table end (most of its connectors too) and it arrived disassembled.
I've been looking at pictures of used machines trying to work it out, but the screens always seem to obscure what I need to see, and the only manual I have to work from doesnt match up to my machine in this area.

Does anyone have any info or a clear picture of that connection area in the work stand tank or a schematic showing it?

After the amount of work I've had to do to the insides to get this far, its frustrating to be held up on such a simple seeming detail.

[MrFluffy]

Anyone? I'm just asking if anyone can snap a clearish photo of their edm, showing where the discharge cables bolt onto the table and which connection points have a link connecting them together.
I've spent a few nights watching youtube videos and google images but can't seem to find any that show the right aspect to use.

I *think* all the lower half of the rails go to the lower stand, the upper half goes to the upper stand, and all the cable outers are connected to earth at only the machine end.
Then the two short cable up to the bottom of the box above the guide area sits on both the lower stand and upper stand so it can sense the voltage back to the system. This is confusing me because currently those short wires are the only one still screwed into anything, and both terminals from it are screwed to the same termination point on the stand isolator block.

[MrFluffy]

Its sorted, for posterity and for anyone else searching, the cables tagged red in the machine cabinet are the EARTH side of things, as apparently red was a japanese earth colour for this era machine. So anything red eventually goes to the outside of the junction block where the mounting screws take that to table ground.
The PIKA relay sits astride the two wire die connections, but the red side of the pika relay connects to table ground, and it is commoned together at the relay, the other two connectors on the right of the contactor go to upper and lower wire guide dies via the isolated junction blocks. Its function I think is to be to inject a HF signal to do micro polishing during the cut (thanks here too for that nugget awemawson) and if you put a oscilliscope across the outputs, you will see a hf waveform applied during cutting conditions. I measured it about 4v intensity but my old scope is not fast enough to measure the frequency.
For the sense cable which connects to the box on the machine worktank frame itself on my machine, the red terminal goes to table ground, and the black terminal to the feed for the lower wire die, this lets it detect short conditions on the wire and feed back voltages to the control.
I've added the diagram from the maintenance manual from a different machine showing this area in case it helps. You can find the link to the manual download in my other thread on here about my bf275.

If you are still unsure, and you have a scope, you can see the dc edm pulse if everything is working at the connection pairs and can see you have the polarity correct on the trace.
If you are struggling with the same once you know its red for earth, it all makes sense. Obvious really then. I have had red for +ve as a colour code drummed into me my whole life so not so obvious for me.


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[awemawson]

Glad that you are up and running, and very glad to have been able to help