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foresthome

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One POTS line for two jacks

Hi,

I'm not sure if anybody can help me with this but here it goes:

I have a POTS line and I would like to split that line for two jacks. I assume is not possible for the line to work at the same time from both phones but at least I would like to make it available to two different phones when need it.  Is it possible and if yes, how do I do it?

Thank you for your help!
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ShareefHuddle
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POTS is just like any other phone (land)line. You can just put a splitter on it.
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moon_blue69

You can use it at the same time if you split it.  Both phones will be on the same call.  Almost all houses are wired this way...everyone can pick up the phone and talk at the same time.  Those jacks are usually daisy-chained.  Not a good installation method...hard to trace and troubleshoot...but it's cheap.

Where is your phone line terminated?  If you're in the NID (plastic box outside the house), then you can twist on both pairs of wires to the binding posts.  You can get quite a few wires on that same post.  I've had up to four wires on each.  Gets a little hard to hold them in place without getting shocked, but it'll do.

If you're inside and have it punched down to a 66 block, then you can put a bridge clip to the other side and puch down a second line.

If you have nothing...just an existing line, then use a tap splice connector.  It's filled with gel to keep out water, air, dust, etc.  It's NOT a butt splice connector.  A butt does not give you an extra line...use the tap splice.  You can find it at Home Depot, Lowe's, or most decent hardware stores.  I don't know if Radio Shack has them...nor would many of the employees.  You can also buy them online, but shipping would cost more than the product. TMUR-01.jpg
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ASKER


thank you all for your answers.

Here is what I actually need to achieve...

I have two pots lines and two fire alarms. A fire alarm requires two active POTS lines. I am looking for a solution to split those POTS so that each fire alarms can have two phone lines. I can put a splitter and connect to the same phone line but I'm not allowed to do that. I need two different phone lines.

Any help would be appreciated.


Well you can run a cross connect at your phone block and hope they don't notice. I know you don't want to hear this but you should probably just get a couple more POTS lines :)
Hate for you to have a Four alarm fire and noone knows about it :) lol

I agree it is not a proper setup but there are more than two fire alarms and it would add up significantly to our monthly bill. The extra POTS will definitely be added into the next budget.

Can you please explain more about the cross connect?

In an ideal situation, you have two phone jacks at each alarm location:
  Alarm1: Line1 & Line2.
  Alarm2: Line1 & Line1.

You can't wire them up with the same primary line.  The interruptor would kill one in favor of the other, so in the event of a simultaneous trip, the second alarm would have a delay finding an available phone line.

You didn't answer yet:  how are your lines terminated right now?  That determines how to get everything wired.

If it was me, I'd disconnect all jacks and run new wiring from the telco's MPOE.  One Cat5  cable to Alarm1.  One Cat5 cable to Alarm2.

Use White/Blue for Line1 (typically Green/Red).  Use White/Orange for Line2 (typically Yellow/Black).

Wire up the jacks the same way...don't mix up the colors.  For Alarm1, plug primary phone line into Line1.  For Alarm2, plug primary phone into Line2.
There's nothing wrong with using two phone lines like this.  The backup line is a requirement for UL.  It's not required to be dedicated, only that it has the ability to seize the line.  Some alarm hardware label this as an RJ31X.

A problem with "dedicated" phone lines is that they're sometimes canceled because they aren't assigned to anybody, and there's no call volume that shows up in PBX reports.  Cost-cutting measures dictate that unused lines are canceled...and the alarm system is disconnected.  You might not know it for a couple of days, because the telco will leave 48VDC on the line, with no dial tone.

Use existing lines from your standard rollover group.  Those will never be canceled.  And, you'll notice right away if it gets disconnected.

Now, you don't have to pay for _any_ dedicated phone lines.

There's no safety in using dedicated lines.  Does your local authority dictate it?

Stop and think about it...there are a few ways to get an UL-approved communication to a monitoring station:  POTS, cellular link, radio link, internet link, and hard-wired.  You don't need a dedicated internet connection just for your alarm service.  You share the existing link.  The panel polls at intervals, and you'll know when there's a network problem.
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aleghart
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Sorry...I've not used two phone lines for a while.  We've had radio, cellular, or internet connections, so no need to mess with phone wiring for a backup.

I have four POTS lines for four fire alarms but it's not OK since there are two lines required per fire alarm panel. I would basically need a total of eight POTS lines but that gets too expensive. I was trying to get those lines crossed somehow so I could end up with two different phone lines per fire alarm panel.

Thank you!
At that point, why not invest in a quality multi-zone alarm system?  The upfront costs are a bit higher, because the alarm montioring company isn't subsidizing the "free" systems.  You should be able to split out each zone with its own controller, users, call list, etc.  Since you have control over the wiring, I'm assuming it's your own facility...so no arguments from the users/departments/tenants about getting a better system.

Consider using an internet connection as the  primary or secondary.  One internet connection can service all of the alarm systems, as long as it's not an ADSL connection on the same copper phone line.  An IP-based transmitter has to be matched to the receiver at the monitoring center.  It can send the same info as a DACT over copper POTS.

I'm not clear on the interpretation by NFPA on installing the RJ31X before internal systems...but I think that shared wiring between multiple RJ31X jacks might break something.
Some IP connectors will do more than just report to central station.  I know of one Honeywell upgrade that gives the user a virtual keypad via iPhone app, and can operate without central station monitoring, using text or email to directly notify users.

OK,

I asked a phone technician about this and he told me to punch the same wire to both pairs in the block without cutting the wire... I had no idea that I can do this...Now it works great!

Thank you for all your help!
You can punch the same wire pairs down to multiple points...a daisy chain.  We did that for basic line sharing between six users of a fax/modem line.  It ain't pretty, but it works.