Emergency transfer equipment

[Tripoth]

Not too familiar with it because everyone and their grandfather has a cell phone these days, but I do understand having some land line use in an emergency.
Have a site with a few of these modules and I have a question.
The lines going into the units are ground start.
I don't see any external power supply for the units, so I am assuming(I know where that gets ya) the power is coming from the switch.
If the system goes down, what would be giving these units power to activate the ground start lines when someone goes off-hook?

 

[4merAvaya]

The older units required a ground start button at the designated phones. The new units (Porta Systems, Lucent, & Avaya) have internal sensors that automagically do the ground start when the station goes off hook.

Installation instructions for the Lucent/Avaya 808A Emergency Transfer Panel are found in document 03-602518 (Comcode 700451024).

Kevin

 

[PBXTech]

http://support.avaya.com/css/P8/documents/100016260

 

[Mamoose]

I just went through this in Kansas. I had a Tone generator which was giving a little trouble and asked Avaya to change it out.
Because we are a hospital and wanted as little down time as possible I investigated this thoroughly. I found our 808's get their power through a seperate -48V supply. I also found no land lines connected to the 808's. We have PRI trunking so I called AT&T and asked them how this was supposed to work and they saud this is a feature which is not offered any longer.
In the end AT&T offers a feature which, when activated by a phone call with a password, will send calls from our PRI to a specific phone number.
We worked around our issue but we plan to route calls to a cell phone which is set up in a hunt group with several other cell phones kept in a drawer until needed. Trouble will be the batteries and occasional testing and we haven't worked through those issues yet.

 

[wellco9530]

They...( the lines) don't require power when the switch goes down to get dial tone...they require ground on the tip side of the line to draw dial tone....what the power does is hold the relay open while power is applied to the unit...when power goes away ( in case of a power fail condition) ground is applied to the tip side of the unit when going off hook on the line...If you notice there is a station in, station out, trunk in and trunk out on most of these type units...
Like 4merAvaya said the really old one's had a button on the power fail phones that applied ground to the line to draw dialtone...today's units will momentarily do it for you...This is strictly for copper CO type lines (ground start) most switches today have DS1 services either T1's or PRI's and don't require them but they are also dead in the water during power outages.....

 

[Tripoth]

Thanks for all the information.
How can you tell an older unti from a newer unit?

 

[wellco9530]

Most of the older units you find on Avaya/Lucent switches were made by Porta...The newer ones are branded Avaya/Lucent and will be something like a 808A Power Transfer Unit if memory serves me correctly

 

[jfh9219]

The move to ISDN-PRI eliminated the need for a lot of the old analog transfer equipment. Years ago I installed a Gordan Kapes PFT920i to allow for ISDN bypass. This is a very slick system. You route a PRI trunk with a D channel through it. You can wire it for automatic switching or manual bypass. It supports 24 external POT lines (strategically located), provides ACD functions and works both incoming/outgoing. I use mine for the rare times I need to bring the PBX down for an extended period.