kenmeans

Your post does not make any sense to me. What are you tiring to do? If you are trying to turn on the MWI lamp then you would need to have the VM system dial the MWI code of the PBX or if it is a RS 232 integration then you would need to set the link to the right PBX type. It sounds like you are trying to do this on more than one PBX at a time and you may not be able to archive this unless some conditions are met.

What kind of VM system is it.

ngseelon

Kenmeans,
Thanks. I design telephones for PSTN. I got a question posted to me to make a phone that message waiting lamp works in various pabx's.

The specs given is as follow:

Nortel - Logic on the message waiting line card interrupts the -150 V dc signal at 1 Hz intervals to provide a flashing message waiting light.

NEC - - 80Vdc steady or 60 IPM flashing

Avaya - -48Vdc (standard) or -85~165Vdc (with optional hardware) at 500ms On and 500ms Off repeated.


Alcatel - 10V rms connected by pulse ton = 60ms typique max =80ms and it is possible to apply 60v rms with the same typical time

That's all I have to work on now. I have no clue on what all those sentences means. Need to translate that to technical and waveform examples.

Thanks for helping out.

MSYoung

The sentences are as technical as you are going to get, looks like they are quoted from the specs. DC does not have a wave form, it either is or isn't present. As each sentence states the presence of an MWI signal is indicated by interrupting the DC voltage at various intervals except Alcatel which sounds like it is AC with the reference to rms voltage.

You will have a difficult time designing one phone to work on all of the above PBXes. Probably will have to put four different MWI networks in each phone and have the buyer select which one to use. This will raise the price and MWI is just one of the problems you will need to overcome.

I will assume that your phone is analog because digital will open another much larger can of worms.

__________________
Do not meddle in the affairs of dragons for you are crunchy and taste good with ketchup.

Marty

kenmeans

This looks like it meets all specs but the Alcatel. Not sure why you would need a phone that would cover all of the PBX's listed it would seem that Alcatel is trying to sell it's own phones.

Viking VIK-LM-1A Message Waiting Lamp


Specifications:

* Input: 80V DC to 150V DC message waiting voltage, minimum 40V AC ring voltage

ngseelon

Kenmeans,
Thanks for the comment. Actually, the phone is intended for generic and can be set at the factory during production. These options are not issues in the design but to understand what are the specifications for each options(PABX). I am still stuck here. I need to get hold of the specs for each analog pabx message waiting signal output. Do you know where I can get these spec? Thanks.

kenmeans

Well it should be as easy as looking at the websites of the manufacture and looking at the specs. Or calling the company and asking for the spec's