# DMOC 645 cables



## Jan (Oct 5, 2009)

Hi guys,

Has anyone ever replaced the cables on a DMOC? 

Or how to extend a 300Amp cable just a little bit? About 30cm.


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## electricmini (Oct 21, 2008)

I've seen video of one of the Ford Ranger motors (also a Siemens) running
just fine with extra-long cables (actual one of Colin Kidder's videos where he's figuring out the CAN commands to run the DMOC)

The DMOC comes with cables, and the Ranger motor has them too, so they were just bolted together.

You would loose the shielding, unless you use a metal box, shielded cables and special EMC cable glands. Both RS & Farnell carry those (they're not cheap) but I've been struggling to find shielded motor wire
I know EVTV have it, but shipping would be expensive from the USA....


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## piotrsko (Dec 9, 2007)

You can buy braided wire, also known as ground strap that can go as large as 0000 wire. Or you can run a 22 gauge bare collection wire under a couple of layers of aluminum duct tape.


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## Jan (Oct 5, 2009)

Hi Mini,

Everything OK? 

Yes, it's hard to find those shielded cables localy. I've dismantled some cables, and I think that I can reuse most parts if I find new cable. Only the cable shoes and of course the crimping stuff isn't reusable.

But first I have to find 35mm2 shielded cable somewhere...



electricmini said:


> I've seen video of one of the Ford Ranger motors (also a Siemens) running
> just fine with extra-long cables (actual one of Colin Kidder's videos where he's figuring out the CAN commands to run the DMOC)
> 
> The DMOC comes with cables, and the Ranger motor has them too, so they were just bolted together.
> ...


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## Jan (Oct 5, 2009)

piotrsko said:


> You can buy braided wire, also known as ground strap that can go as large as 0000 wire. Or you can run a 22 gauge bare collection wire under a couple of layers of aluminum duct tape.


Braided wire to make my own shielded cable? Might be an option... Thanks.


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## Jan (Oct 5, 2009)

Considering an alternative option:

If I drill three new holes in de back of the motor's connection box, I don't have to extend any cable. 

In this connection box is a plastic holder placed. Remounting that thing mirrorred and add three new holes seems to me a more effective solution.

Or is it a bad idea?


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## electricmini (Oct 21, 2008)

Jan said:


> Considering an alternative option:
> 
> If I drill three new holes in de back of the motor's connection box, I don't have to extend any cable.
> 
> ...


I think it's probably a bad idea...

If it's one of the Siemens motors, then debris that's inside the terminal box
can fall down into the chambers where the stator windings are. Even though they are insulated with varnish, it's probably not a good idea to get metal swarf/particles in there!

Also, the internal cables to the stator are stiff, and will be almost impossible to reroute or bend without damaging the varnish and/or insulation

What's wrong with using a metal box with EMC cable glands?
Together with shielding braid/foil/earthing strap and regular 35mm2 cable, you'll get screening and extended cables. You can always just bolt the cables together inside the box, covering each bolted joint with adhesive-lined heatshrink...


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## Jan (Oct 5, 2009)

electricmini said:


> I think it's probably a bad idea...
> 
> If it's one of the Siemens motors, then debris that's inside the terminal box
> can fall down into the chambers where the stator windings are. Even though they are insulated with varnish, it's probably not a good idea to get metal swarf/particles in there!
> ...


Yes, the internal cables are really stiff, but bendable and the insulation can handle it. But I'm going to add some more insulation because the space they have now is less then before. 

Preventing debris from falling into the motor is a good point. I'm not that far yet. Planning to do that this weekend. 

I've mounted the motor sideways, so I think keeping debris out of the motor should be possible with some paper and tape.

There is nothing wrong with an extra junction box. This option just feels more appealing. Shorter wires. Less connections. Less space. Prettier.


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## Jan (Oct 5, 2009)

OK. Here's a really stupid question:

Anyone knows what sizes those small bolts are, that attatch the cover to the bottom plate? They're something odd between M3 and M4.

I've been searching for a week now where the heck I left the jar with those bolts. There's something very mysterious going on in my work shop.


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