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RJ-45's instead of RJ-11's for voice 1

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nessman

IS-IT--Management
Oct 17, 2006
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Watching one of my competitors cable up some new construction for a customer of mine (they outbid us for the cable job). They're using RJ-45's for voice drops instead of RJ-11's ("that's because we're using CAT5e cable for voice"), and they're mounting them upside down with the pins on the bottom instead of the top.

I can see my customer is getting what they're paying for.

So... you have the risk of someone plugging their computer into a voice jack - with the risk of a.) frying the NIC and/or b.) crossing pins in the jack if it's not put in properly.

There's two ways of doing a job - the right way, and the wrong way.
 
Many many many people use rj45s for phones. Most people will label the jacks or color code.

Blue being date

White for phone.

How much unplugging will you do once everything is set up?

Also the risk you are talking about is extremely low.





 
I'm a vendor too and never ever wire a voice drop to an RJ45. I see zero advantage to doing it that way - especially if you're termination on the frame is a 66 block. To me it's it's lazy and/or not knowing any better.
 
We use RJ45 jacks for all voice and data connections. Advantages are many, but mainly, if you have only one jack left in your "bag of tricks" it is going to work for voice or data and you don't have to worry about coming back to replace it at a later date. When you are trying to keep up with thousands of connetions in multiple buildings, that is a big advantage.
 
Also wiring with rj45 will give you room to switch to a different phone systems. Some now require rj45 and the cables the phones come with are rj45.
 
What phone system uses an RJ45?
 
in the early 80's AT&T set it standard as a RJ45 ,with it's 4 pair cable to adapt to it any , of it phones & data modules , depending on what pairs were used or needed is what you wired at the 66 block
 
what you wired at the 66 block

should say cross connect at the 66 block
 
yea the upside down mounting of the jack is one thing but rj45 for voice is becoming very normal nowadays.

we do it and all of our competitors do it.

also for IP phones they require it.

So wire the business once and they are ready for whatever comes their way.

 
Not sure you guys are following me here... I've never seen an analog/digital phone system (NOT VoIP) that used an RJ-45 connector on their phones. VoIP is an entirely different beast that uses existing network cabling.

If they're upgrading from analog/digital to VoIP - there's no need to run new cable - they use their existing network infrastructure - VoIP phone plugs into existing jack, PC plugs in to VoIP phone. Done. Just have to have PoE switches, VLAN's set up, QoS, etc... etc... and PoE isn't even necessary if your phones will take an external power supply or an inline PoE power injector.

If they're doing VoIP from the get-go (i.e., new construction), they're using an existing data drop at the user's desk - there's NO need to run a separate network connection dedicated VoIP, so long as their switches are configured properly for it. Some customers insist on it - but that's because either they have network security requirements that call for it, their network infrastructure is not ready for it, or they don't know what they're doing. In most cases, VoIP phone systems integrate with their networks.

What I'm talking about is an existing facility with a analog/digital phone system and a separate data network. And for that, you have to use RJ-11 jacks for voice - otherwise you're sending 48 volts from the PBX (or telco if they're dedicated lines for fax, alarm systems, etc...) into a NIC and creating the potential for damage to the customer's equipment - can't plug an RJ-45 into an RJ-11, and there's a reason why they went that route when the standards were created. If you're punching your voice cable down at the frame into 66-blocks, BIX, 110, etc... they're being cross-connected to the phone system, and not into your network infrastructure.

Yes, I've seen customers insist on terminating everything to regular 110-patch panels with RJ-45's and using CAT5 patch cables to cross-connect everything, but it's very expensive, looks like crap, a nightmare to maintain - especially when you're getting into 100's or 1,000's of phones), and in the end creates more work. In the real world - you terminate all your voice to 66-blocks (or BIX - I prefer 66 blocks) and use inexpensive cross-connect wire to link everything up.

 
We do rj45 period unless the customer request otherwise. We terminate to. Cat5e patch panels labeled voice and data, jacks are color coded white amd blue. Blue8 and orange etc. This way they are fully ready for anything including moving phones on their own.

"Friends,Romans,Countrymen lend me your ears I come to ask for help and to give it, lets not argue on who is best or worst lets just help each other
 
I've been in this business for over twenty years and have NEVER used an RJ45 for voice. Or for data. RJ45 spec defines the wiring as one pair on center pins and a programming resistor on pins 7 & 8. I'd be willing to wager that few of you have really used an RJ45 either.

That said, any new cabling projects use 568B wiring to a patch panel or 110 block. Can then be patched to voice/data/fax/etc. Generally there is no harm in plugging a phone into a jack patched to Ethernet switch, nor is there harm in plugging a network device into a voice jack - at least a "one pair" voice jack where there is no voltage on 3 & 6.
 
nessman-

they make wire management to organize the patch cables... the installs i do look beautiful

maintaining is if anything easier with patch panels. All i have to do is plug in a patch cable instead of cross connecting/punchdown

i honestly prefer it and all of our customers do as well. The only time we now use 110 blocks/66 blocks is when it is entirely necessary

i even terminate 25 pair amphenol from the pbx to a patch panel. It really makes moves alot easier
 
What about the RJ11 cords bending up pins 1 and 8 rendering the jacks useless for anything that uses those pins.

I have installed 568B to patch panels for VOIP voice, but make custom cords with RJ11 at one end and An 8P8C plug on the other for fax machines to use.
 
It pretty much boils down to using the correct jack for the application. If an analog or digital phone requires only 1 pair, then use 6p2c jacks, 2 pairs go with 6p4c, 4 pairs use 8p8c. Color coded jacks & cabling is a plus as are good labels. [smile]

I [love2] "FEATURE 00
 
I still use RJ11 for voice for the simple reason, a customer can not plug their computer into the phone jack. It is a pain for me to carry both but the alternative causes to much confusion for my customer. Labels fall off and desks get moved in front of jacks so you can't read them.
your competition most likey finds it cheaper to carry only one type of jack.It's always nice to see others doing things wrong (like upside down jacks), if I can I try to casually point it out to the customer without being critical.
If customers want us to compete on price only, they must be prepared to get what they paid for.
 
"Dex, I've never seen a jack with only 2 pins [smile]"

Doh! I was thinking of plugs. [purpleface]

Good eye Jeff! [smile]

I [love2] "FEATURE 00
 
And today... ran into the very reason why voice jacks should never be wired up as data. Doing some moves at a customer site today... office furniture in front of the wall plate - customer already ran the CAT5 patch cable for his computer and phone line for his phone before furniture was moved in front of it. No network connectivity to computer, phone dead. Tone out phone line - showing continuity across all pins, no tone at 66-block the IDF.

Had to have customer clear out his desk, have maintenance come by, remove furniture (cubicle partitions by the way), turns out - yup... PC plugged into voice jack - getting a nice healthy shot of 48VDC into the NIC (good thing it wasn't an analog line that was ringing jumping it up to 90VAC), and phone plugged into the data jack.

NOW... had my competitor not done this to begin with - everything would have worked the first time around - rather than wasting billable time back to the customer to fix the problem in the first place. This goes to show that the ordinary end user doesn't know the difference. At this facility, data is grey, voice is black. But with jack numbers of 467, 467A, 467.1 and 467.3 - means NOTHING to the average Joe trying to get his computer and phone to work. To me it does - but that's my job, not the end-users. 467 and 467A are data, 467.1 is digital voice (WH/BL pair) and 467.3 is for analog voice/fax/modem (WH/GR pair). That's the wiring standard at this customer - but the jacks are not correct for voice.

Of course, if the NIC on the PC or laptop has pins 4-5 protected and not connected to anything - sure little chance of causing harm (bear in mind for PoE applications 4, 5, 7 and 8 are used to deliver 48VDC to the device). However, there are places that use multi-line analog phones, starting on pins 4-5 for Line 1, 3-6 for Line 2, etc... that's where you start running into problems with using RJ45 jacks on voice lines. Ethernet usually runs around 2.2VDC, and when you have Line 2 ringing into a PC plugged into a two-line analog jack - you're asking for problems.

The price difference between CAT3/USOC jacks and CAT5/T568B jacks is negligible. No reason not to do it the right way.

If the customer later on decides to dump analog/digital voice and go all VoIP and insists on running VoIP on it's own separate network and they need the voice jack converted to data, then it's more money for you.
 
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