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I'm going to be installing a switch and 40 workstations/printers in a building. All the rooms have raised floors with cable trays running in various grids and there are cable trays going between the rooms accessible from the basement. Most of the runs will be between 200' and 300'. All the runs will be going from the switch in the computer room, under the floor in cable trays and then popping up and directly connecting to the workstations/printers.

I remember back in the day it was a big deal to use solid cable for horizontal runs but that was usually between a switches or other stationary devices. I've been seeing problems with similar situations where a solid cable was used because people move stuff around and eventually the conductors break.

Now in the modern day does anyone see a problem with using stranded cables for this type of installation?

murisonc
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1 Answers1

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Use solid core wire for structured wiring (in-wall, above ceiling, etc), it's cheaper.

Use stranded core wire for everything else (eg, wall to computer, in-rack, patch panel to switch, etc)

To directly address the question as stated:

I remember back in the day it was a big deal to use solid cable for horizontal runs

That makes no sense at all - whoever made this a big deal was uninformed at best.

that was usually between a switches or other stationary devices

As stated above, solid core is for structured wiring, not "stationary devices" which have a tendency of moving over time. It should only be used where the endpoints are part of the building.

I've been seeing problems with similar situations where a solid cable was used because people move stuff around and eventually the conductors break.

Correct - which is why you never use solid core outside structured wiring.

Now in the modern day does anyone see a problem with using stranded cables for this type of installation?

You never cited any actual problems with using stranded core cabling in the first place. The main reason it wasn't used for structured wiring is price, stranded is more expensive than solid core. A minor secondary reason is that solid core is much easier to get a good connection in punchdown blocks and keystone jacks.

Note: There are different C8P8/RJ45 ends for Solid and Stranded wire. Be sure you use the correct end for the wire if you want a reliable connection. The pins when viewed cable end-on look straight for stranded wire, and look forked for solid wire. Diagram courtesy cableorganizer.com.

Chris S
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  • Nice canned answer but it doesn't answer the question. How about from switch, under floor, up from under floor and directly to computer? I don't have the option of a wall connection. – murisonc Apr 04 '14 at 20:43
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    Yes, it does. That's not structured wiring, so it's in the "everything else" bin. Also, I'd recommend not doing that in the first place. – Chris S Apr 04 '14 at 20:48
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    +1 I can't tell you how many times I've seen solid-core terminated in RJ45 plugs, directly to the server. That is *not* a good situation, for many reasons. – EEAA Apr 04 '14 at 20:52
  • @murisonc You really should reconsider your no-patch-panel situation. – EEAA Apr 04 '14 at 20:53
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    Ok, I get what you mean. Unfortunately I don't have a choice because of the way everything was setup 15 years ago. They won't let me put a patch panel in each room. Typical Government craziness. – murisonc Apr 04 '14 at 20:55
  • Is the only reason to use solid, instead of stranded, cost? Because where I buy cables. stranded are mostly cheaper than solid. Isn't stranded worse for sockets and stuff like that. I've also read that stranded lose signal quicker than solid, is that true? @ChrisS Is cost really the only benefit of solid? – KaareZ Jul 27 '15 at 19:07
  • @KaareZ Updated the Answer with some minor details. For one off runs there's really no difference. When you're doing a hundred runs a day the differences add up quick. All cable has to meet the minimum specs for it's category; anything above that shouldn't be assumed (even though it's quite common from my experience). – Chris S Aug 05 '15 at 17:25
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    @Kareez - One practical reason to avoid stranded cable for structured wiring is that it may not terminate correctly on patch panels or wall jacks. Most use some variation on a 110-style punchdown, in which the PVC jacket and copper conductor are pinched between two little metal bits. The design assumes that the "pinch" will slice through the jacket to give you a good metal-to-metal termination. With stranded cable, the conductor is compressible, so the termination may not completely pierce the jacket. – James Sneeringer Aug 05 '15 at 17:48