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telephone not ringing out

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eti232027

Vendor
Jul 14, 2014
15
NG
i just installed alarm panel in a large residential estate, i used the pabx extentions of the houses to communicate with the cms, i noticed that when the alarm panel is connected the telephone line will not ring out.i check the out voltage it was low, this was due to distance. Is there any device I can use to improve the voltage on the lines to make the phones ring out?.
 
What does "not ring out" mean? If you're having trouble on outbound calls, the PBX may require a 9 or some other prefix. FYI - in our part of the world, it is against code to run a fire alarm thru a PBX. Take care in that regard.
 
What I meant by does not ring out is that when there is an incoming call the telephone handset does not ring out.I need to boost the voltage so that it can ring out.
 
What country are you from? If UK you will need to have balun or socket with a resistor in it (other countries may be the same). Tend to be refered to as Master baluns or master sockets.



Robert Wilensky:
We've all heard that a million monkeys banging on a million typewriters will eventually reproduce the entire works of Shakespeare. Now, thanks to the Internet, we know this is not true.

 
You don't say what type of phone system you are connecting to

You could be trying to connect to a digital extension or IP?

As mforrence says it maybe against local regulations to put the alarm through a phone sysytem, if you have to put it through a phone system i would try and pick a power fail extension and configure the extension as a hot line or something so the alarm panel could dial out in both situations (powered and non powerd telephone system)

Could be embarrasing at least if you get this wrong [blush]



 
am actually connecting to alcatel pabx which is an analog telephone system
 
What I meant by does not ring out is that when there is an incoming call the telephone handset does not ring out"
Thanks for the morning chuckle!!

Will just assume you mean the device does not "ring" then.

7 questions...

-What PBX system is it?
-How are you exactly wired up to it? what interface if any are you using with the PBX?
-With the alarm disconnected - how many volts when idle?, how many volts when ringing?
-With the alarm connected - how many volts when idle?, how many volts when ringing?

Best to sort this out in case the carrier has an issue sending voltage or an ATA device or the Alarm box has issues.
One test is to wire up the alarm direct to a line without the PBX.




=----(((((((((()----=
curlycord

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Toronto Canada
 
Thanks Curlyword,
the answers are as follows:

-What PBX system is it? alcatel omnipcx
-How are you exactly wired up to it? one pair cable connection. what interface if any are you using with the PBX? no interface
-With the alarm disconnected - how many volts when idle?, how many volts when ringing?39.5v
-With the alarm connected - how many volts when idle?, how many volts when ringing? 40.6 v
Thanks this what I have done so far
 
Ring generator should be in the neighborhood of 90VAC. The voltage you describe sounds like dial tone voltage and I bet that is DC. Please clarify.

Always look out for the next tech. because one day it will be you!
 
yes it is dc .how do I increase it?. Am working with analog telephone mind you.Thanks
 
This is pretty basic stuff as far as telecom goes. When you connect the set to the PBX, you should measure about 48V DC. This is normal and so is a bit of a drop if the loop is long. The alarm "line" you refer to should be connected onto a trunk port of the PBX (this is normal too). Alarm installations usually have special jacks for this. The alarm line shouldn't have anything to do with the station you're talking about.

When you dial that station's extension number, the PBX port should send 90V AC to the set to activate it's ringer. It's ok for it to be a bit less on a long loop too. It should be easy to measure with a meter and test. Just dial the extension number......the set should ring and you should be able to answer the call. Even is the voltage is too low to activate the ringer, you should still be able to answer the call just by picking up the handset.

If you're trying to connect to one of the alarm panel's sensors, then that's a different story! It's simple......you can't do it! In fact, you're likely to damage the alarm system by running 90V AC to it.

If you don't understand the concept of what I'm talking about, you might want to get a qualified telecom tech out to give you hand.
 
thanks for your contribution. It is true. When you dialed the number from the pbx even it does not ring out if you pick it up you can talk. All I want to solve is to get it ring when there is a call. Is that not possible?.
 
Measure the AC voltage and the current. You might even want to check the ringer on the set if there is sufficient AC voltage. Try connecting the set back at the PBX port and ensure the ring generator is working on the PBX side.

If everything checks out, you could try doubling up on the cable pairs going to the set (assuming you have extra). If not, then that Sandman unit will likely do the trick..........it's all a matter of that 90V AC! That's what makes the phone ring.
 
Great thanks a lot I will try it out and let you know.Good to know people like you. I have really gained a lot from your contribution .
thanks also to tek-tips.com its a wonderful place to be.
 
Did the phone ring before you connected the alarm? you still haven't told us which country you are in. The UK has a system where the capacitor for the ring circuit (not a resistor) is in the master socket and from there to the secondary sockets, it is a three wire circuit. The third wire carries the ring current so if you have somehow taken the master socket out of the circuit none of the phones will ring as they have no capacitor in them.

Another possibility is that you have exceeded the maximum REN the PABX is capable of driving so try less phones (especially if they have a fax as these are usually high REN). But then again the alarm panel may just be faulty (Capacitance to earth so the ring current is going to earth, it may work if the line is reversed).
 
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