atcomsystems.ca/forum Forums Wiring - Telecom Carriers - Trunks & Services Security, Alarms and Paging Paging System for Large Campus

Good morning ~

We are using the MOH/Paging module as part of our Mitel 2000SX Light system to provide paging.

We have 100+ buildings that could potentially need speakers (1 for most, 2 for some) and hope to use newly installed phone pair to take the signal from two different demarc points to the various buildings.

Can anyone recommend a particular amp/speaker setup for this? Any advice would be most welcome!

Thanks,
Jeff

Wow, 100 plus buildings. That's rather an ambitious project.

I'm not sure I would recommend audio over twisted pair for that extensive a system. What distances are we talking about?

Hate to say it but this might be a good application for an IP based distribution to each building. How is your networking between these buildings handled?

-Hal

Some up to 2000 feet.

The only available connections between buildings in the phone wiring. We have brand new pairs to each building so that's a plus.

Jeff

I'm not a big believer in powered speaker systems, but with only 1 or 2 speakers per building it might be just the thing.

Something by Valcom maybe. For the long runs you might have to double up the pairs.

Is this an "all call" configuration or do they want this zoned?

Sam

Some up to 2000 feet.

What's the longest combined distance from the beginning to end? I assume that some if not all buildinge will be bridged off this run?

-Hal

This will be an "all zone" system that is only used for the most severe of emergencies.

We have two nodes and I was thinking of having the amplifiers in each node. The buildings home run back to their respective node so that is where the distance comes in.

Jeff

So you are saying that the 2000 ft run is from the farthest node to the PBX location?

Also, what does your wiring consist of? You say it is brand new, what kind of cable?

-Hal

Right. Everything home runs from the building back to the node. Pair 1 in Node 1 corresponds to Pair 1 in Building 1.

It's Cat3 phone wire to all homes.

Jeff

Well, I think you may have put the cart before the horse by installing wiring then trying to figure out what to do with it. You probably could have saved a bundle on wiring.

You may want to look at Valcom Encompass. I believe it's an IP based system with amplified Valcom speakers, it is what you are looking to do. Give them a call.

-Hal

The wiring actually had to be installed - old wire was in bad, bad shape.

Using extra pair for the paging system is add-on to something already in-place.

jg

With 22ga wire you aren't going to get very far trying to drive a speaker directly, even from your node or hub to a building. If you try to put a 70.7 volt system on it don't expect to use the remaining cable pairs for anything else because of the cross talk.

The problem with an IP based system is that you will have to come up with you own DSL system in order to put the ethernet on those cable runs. But, like I said talk to Valcom. The should have a solution, either IP based or conventional.

I wouldn't try to reinvent the wheel here, I'm sure this has already been done.

-Hal

jg, the problem here is that if you keep the audio level, on these building-to-building runs, low enough to prevent cross-talk To the phone conversations,2 things happen.
1. so low that you may not be able to boost it enough without excessive noise.
2. cross talk From phone conversations.
The paging signal Really needs to be in a separate cable. And all you really need is a 1 pair cable.
Hal, do you think he could get away with some 1 pr areail (sp) drop, direct buried. I don't see the jacket being a problem, but I wonder how it will fair in picking up noise from nearby AC, etc.
John C. (Not Garand)

I don't know how well that would go over considering that new cable has just been installed. Somebody didn't do their homework here for sure. Best bet is to get it on what's there, question is the way to do it without spending a fortune.

2000 feet is doable for a balanced audio pair however there is the other factor of a run to speakers in each of the over 100 houses. Dunno, but I'm seeing a DSL/IP setup for each house.

Question for jeffgoza: is this some kind of senior/assisted living community since you mentioned houses? Do they have cable TV in each house?

-Hal

I did an installation like this once and if my memory recalls correctly, We used a valcom V-2001A and then we used the V-1020C speaks and the V-1030C horns. We had to put a VP-624B power supply near each horn or speaker, But you may be able to use a VP-324 power supply. But I remember us trying to decide between a 70 volt system and a Valcom, and we went for the Valcom because all of their One-Way Speaker's and Horn's are Self-Amplified, so this worked pretty well. and i don't think that they ever complained about it, but i only worked for that company for about a year after the installation. Hope this helps.


Thanks,
Daniel

But was the project like this with the distances, number of locations and wire topography?

I can't imagine an amplified speaker like that in a house hanging off a few thousand feet of UTP not making noise all the time.

-Hal

Hi ~

Actually we are a 24/7 care facility for folks with Mental Retardation. 500+ residents and over 1300 staff. We have a signaling system (tone only) that we home-built but need something - only in BIG emergencies - that can relay them a little more information.

I will contact Valcom and let them look at this!

Thanks,
Jeff

I think that's your best bet. Good luck and let us know how you make out.

-Hal

I had a campus with just a few buildings I did something like this many years ago. I used a balanced output off a 6 watt amp and fed the pair. At each location I either had self amplified speakers or amplifier with several speakers. You need to have isolation transformers so prevent ground loops. If there is a problem with the line picking up noise then you could add a relay to short the line when there is no audio

If there is a problem with the line picking up noise then you could add a relay to short the line when there is no audio

But that would require an extra pair. With long line lengths you would want the amp at the speaker muted. I think even with a short at the other end the line will pick up noise. A coded squelch would be a better solution but then you get into custom designed and manufactured equipment since nobody makes such an animal.

-Hal