sundance-communications.com/forum Forums TDM Business Telephone Systems Avaya - Lucent Telephones & Systems Definity Project

I'm starting to take on a little project of tinkering with a Definity switch to learn it. I've got several 7444s, 8410s, and 8434Ds I've accumulated over the years. Im going to be given a Definity switch (it is an SCC type) so I decided to play arounf with it. I can punch the 25pair tails down just fine, but I want to know from the veterans if anythign else I'm going to need besides an SAT. Can the 7444 and 8434 be powered alone by the circuit packs or do I need some sort of bulk power to mount on the backboard. I know they have little wall wart plug in types to use with a 400B adapter, but I keep reading about some kind of bulk power supply for closets.

Also, what is the difference between 2 wire and 4 wire digital sets?

Again, I'm just an individual that is going to play with this in my garage and possibly replace my Nortel MICS if I feel comfortable with it enough. I have a great passion for PBX systems and their capabilities, so it is more of a hobby and a great desire to learn.

Any and all help appreciated. Thank you!

support.avaya.com has great documentation on hardware, features, programming, wiring, etc.

generally the 74xx sets are 4 wire and work with tn754 digital circuit packs. external power depends on the station adjuncts, like external speakerphone, display, coverage and expansion modules

84xx are two wire sets and work with tn2181, tn2214, tn2224

some consoles are 2 wire and some are 4 wire and some will work 2 wire or 4 wire

302
302A
302B are all 4 wire

302C 2 wire or 4 wire

302D 2 wire only
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power units
1151A -48v power supply for DCP voice terminal
329 Power Supply for digital sets
346A Bulk Power Supply
346A1 Power Panel
945-1 Bulk Power Supply

Some good stuff to know, AvayaTier3. Thank you for providing that. I have already downloaded tons of books from the website and I'm going to compile a nice reference library in binders once I sort out which software release I'm at.

So, would you recommend local (at the phone) power supplies for the 7444 and 8434 since they have a flourescent display?

I just want to start looking for any other hardware I'll need for this baby.

Thanks again,

I can't speak to the Definity, having no experience with it - but - when I worked on Northern SL-1s years ago, the phones required external power.

On the jobs where we provided bulk power supplies and powered the phones from the switch room we did OK. On the jobs where we powered the phones locally from wall-warts we were forever getting called out on trouble calls. Usually the user had either kicked out the power supply or had unplugged it to plug in some appliance. Then the phone stopped working! Did they plug the PS back in? Of course not! When we tried to bill for these troubles we caught a real ration from the customer.

Just my $0.02.

Sam