V5 Cables


#1

The custom V5 cables or 8 weeks out do you have to use the V5 cables or can we just build our own?


#2

According to the rules, you must use V5 cables or make cables from vex V5 cable material. The official Q&A makes it clear that V5 cable is different than ordinary cable, and the jacket is labeled so inspectors can tell if it is legal cable.


#3

While we are waiting for the V5 custom cable to ship, we were able to use wire and connectors from Fry’s with our V5 and had no issues. The Fry’s cables had a shield wire with it that we just didn’t use and that is the only difference between the VEX cable. Once we get our VEX cable in we will replace our temp. cables.


#4

How is there a difference between regular phone cable and the vex cable its just 4 wires… i understand that vex wants to limit things coming outside for competitions but some teams work on a tighter budget than others. The other thing is why not use regular Cat 4,5,5e,6 cable the only thing is you have 4 extra wires not connected to anything which is only adding weight to the bot. and even its not enough to change anything…

Some one with vex care to comment?


#5

Vex sends a lot more power through the wires than a phone cable so they use thicker wire inside. Also their wire prices are incredibly reasonable, actually priced competitively from what I have seen.


#6

@tabor473 Ok so than why cant we use any of the eithernet cables they can handle that. just leave the 4 wires tied around the jacket and will allow if a cable is the issue switch to the wires not being use and then your good to go.


#7

It will not pass inspection at qualifying events and Worlds

Other than that, do what you want, but you may damage equipment.


#8

Logically how is it going to damage equipment cable is cable.

I can order 1k foot of cat 5 cable for 50 bucks while only 26 ft of the vex cable is 7 dollars how is that competitive pricing? im looking at a stand point from the teams who don’t have the funding…


#9

How do you plan on crimping a cable with that many pins? Individually instead of all the pins at once?

Also it looks like none of the standards for PoE come close to the power requirements of a V5 motor …


#10

Someone with vex did comment, in the official Q&A where the question was asked weeks ago:
https://www.robotevents.com/VRC/2018-2019/QA/35


#11

To add on, the most common standard for PoE uses 48 V, which requires both boost circuitry at the source and buck circuitry at the sink to be useful. The reason for 48 V is to mitigate the losses (especially heat) from higher currents.

The only remote hope of V5 working safely with off-the-shelf cabling would be if the Brain had boost conversion and every motor had a buck converter, which would require both the Brain and motors to be larger and more expensive.

I think the competitively-priced (yes, I think so too) cabling is far more reasonable.

@dcjrracing11 While Cat5 might be cheap, I wouldn’t trust it for PoE use, let alone V5. Cat6, of which I would trust reputable brands’ cabling, is priced about the same as VEX cabling.


#12

Again, it is not what you wish, but what the rules explicitly state - it will not pass inspection since it is not made from VEX branded bulk cable. Not worth arguing, since 99% sure the GDC will not change this rule.

As for the electrical characteristics needed, others have commented to those points.


#13

I called Vex and they said the cables, ends and tool were in stock and would ship immediately? That was Friday, I’ll let you know when they actually arrive.


#14

Aside from the rules stating that V5 smart cables must be used for competition. Not all cables are created equal, here is a comparison, I don’t have specs for either the VEX cable or the random silver 4 conductor phone cable I had, but there’s a significant difference.

smart_cable.jpg


#15

careful, looks like you stripped the insulator on common of your VEX cable :). Was that using the new VEX tool or you pocket knife?

(humor)


#16

haha, yes I saw that after I took the photo. No, I do not have the VEX tool.


#17

Kids, don’t do this at home…

we learned the hard way at worlds what happens when you short main battery leads in competition.


#18

Black is actually not common, it’s one of the signal wires.


#19

oops - see, that’s why I won’t be allowed to touch nice things :slight_smile:


#20

I just received the cables, ends and tool ordered last week. Also the balance of V5 motors ordered in July, we now have enough motors for (8) per robot. Vex is working through this. Thank you Vex.