Multi-conductor cables

Budzu · 11-29-2009, 06:14 PM

A question for any electrically minded folks:

I want to connect a relay box with a control panel. The control panel needs 12vdc (to power a bcs) and 24vac coming in (transformers housed in relay box), and 4 switched 24vac loads going out back to the relay box.
Can all these 8 lines run together in a shielded multi-conductor cable? Or is there some interference that would be caused.
Also if anyone knows a good electrical forum where I could ask something like this, a link would be greatly appreciated.

Thank you in advance, cheers!

OhioBrewingTechnologies · 11-29-2009, 06:38 PM

Quote:

Originally Posted by Budzu

A question for any electrically minded folks:

I want to connect a relay box with a control panel. The control panel needs 12vdc (to power a bcs) and 24vac coming in (transformers housed in relay box), and 4 switched 24vac loads going out back to the relay box.
Can all these 8 lines run together in a shielded multi-conductor cable? Or is there some interference that would be caused.
Also if anyone knows a good electrical forum where I could ask something like this, a link would be greatly appreciated.

Thank you in advance, cheers!

How long will this wire be? The AC could couple between lines but I don't think you'll have problems. You're not going to couple enough energy to accidentally engage a relay. The BCS should reject ripple on the DC, I expect. Now if you're running this for 100 feet, might be wise to split it up.

Budzu · 11-29-2009, 06:42 PM

That's excellent news! It will be no more than 6 feet and all the loads will be quite low. Thank you for the response

Oh and P.S. should a ground wire be included in the run? I don't think the BCS requires one.

**bad coffee** · 11-29-2009, 07:53 PM

if you're using a metal case, you should ground it.

B

**Sawdustguy** · 11-29-2009, 08:01 PM

Quote:

Originally Posted by Budzu

A question for any electrically minded folks:

I want to connect a relay box with a control panel. The control panel needs 12vdc (to power a bcs) and 24vac coming in (transformers housed in relay box), and 4 switched 24vac loads going out back to the relay box.
Can all these 8 lines run together in a shielded multi-conductor cable? Or is there some interference that would be caused.
Also if anyone knows a good electrical forum where I could ask something like this, a link would be greatly appreciated.

Thank you in advance, cheers!

Often times you can find multiconductor cables with twisted pairs. The twisted wires on the AC lines will cut down on the amount of radiated 60Hz emissions.

gbrewing · 11-29-2009, 08:11 PM

There is a good forum you can ask this at. It is http://forum.embeddedcontrolconcepts.com/index.php?sid=c593f4a1d7ffe861dde647c0bf95efc0 which is for the BCS460

Budzu · 11-29-2009, 09:31 PM

Well I think I only need 1 24vac pair. 24vac negative should only be needed to wire to the switch LED's. Its just the positive going into the control panel, the other negatives go straight to the relays. I hope I'm not off here. Here's the wires bundled:

to control panel:
1 12vdc +
1 12vdc -
1 24vac +
1 24vac -
1 ground

from control panel:
4 switched 24vac +

**airbalancer** · 11-29-2009, 09:32 PM

I used a 14 conductor cable from this company to connect my control panel. All 24 VAC and one pair 110 VAC to power the PIDs. There was 7 twisted pair in it.
Mike

http://www.surplussales.com/Wire-Cable/Wire1.html

gbrewing · 11-29-2009, 09:48 PM

Can you let us know the patterns of your wire? What leads to what?

OhioBrewingTechnologies · 11-29-2009, 10:34 PM

Quote:

Originally Posted by airbalancer

I used a 14 conductor cable from this company to connect my control panel. All 24 VAC and one pair 110 VAC to power the PIDs. There was 7 twisted pair in it.
Mike

http://www.surplussales.com/Wire-Cable/Wire1.html

Now putting line voltage within the same shield would make me much more nervous. Normally you want more separation than that. UL would probably not accept it without an additional layer of insulation around the mains.