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Phantom 911 calls 1

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Neaxtec

Technical User
Jun 13, 2007
5
US
I have a large school district that has NEC SV8300 and SV9300 systems they have been getting phantom 911 calls from one of the schools on a regular basis. the call accounting is set to notify on all 911 calls and seems to be working, however still 3 or 4 times a month we still get 911 calls from that campus. All the 911 calls route through a local Loop start co trunk that is dedicated to the PBX for this function. none of the phantom hangup calls to 911 show up on the call accounting and no notification is sent. I think that it has to be something with the telco line has anyone else had issues like this with loop start trunks recently. What did you have to do.
 
Has enhanced 911 been set up?
Enhanced 911, allows the PBX to transmit a callers’ emergency service identification information to an Enhanced
911 Emergency system. The 911 notification is also provided to the EMG key of a designated Attendant Console/
Multiline Terminal.
Notification to Multiline Terminal
1. At designated Multiline Terminal, the LED of EMG key flashes in red and ringing is heard.
2. Lift the handset or press Speaker key, and press EMG key; the caller’s information is displayed.
3. Press Override key; the Multiline Terminal can override the call.
 
E 911 is not set up however the call accounting is sending emails to the admin groups at each school when 911 calls go out. That is working. however these calls are not pegging to SMDR, as a result they are not sending notifications. I have checked all station and SMDR programming on every station several times. I do not believe that these calls are coming from the PBX. I will be changing the Loop start line later this week to verify my thought.
 
You have an analog phone line that has bad wiring. Maybe a rusty outlet, or a cable that's partially damaged by water, or other physical means.

Then what happens is that at the point where the cable or outlet is damaged/rusty, you have occasional short-circuits on the line. And I don't care how unbelievable it may sound, this happened to me already: the cable short-circuits at random times, on and off, so the line goes off-hook and then on hook multiple times in a minute or even in a second.

There is some mechanism that when this happens, a 911 call is made. Maybe the short-circuits act as dial pulses, and they are translated into digits 911. Maybe you have short-circuits on this line all the time, and occasionally they go through as a 911 call.

But when a 911 call gets originated, your dedicated 911 trunks gets seized, and the emergency response center gets the call. BUT, before they answer the call, the originating station with its faulty wiring goes back off-hook (hangs up), so there is not a completed/answered call, so SMDR doesn't report it. But the Emergency responders do get the caller ID of your call even if your "caller" hangs up before they answer, so they'll call you to find out what's happening.

To resolve this, go to your system, and hopefully, on the line-cards, you have LED-s corresponding to stations, and the LEDs are:
off: if the station is idle
on: when the station is in-use
blinking: when the port is not programmed

Look for and LED that's mostly on, or always on, or blinking erratically. This might take a while to find, but this is your way of finding it. The corresponding phone is at fault. You should disconnect the cross-connect wire from that port so no more calls are made, and then either pull in new cable, or find out what's the fault with the existing one. Probably a rusty outlet.

Here is what happened on my site:
Example 1: A building underwent some construction. Some electrician gutted the walls, and left a phone cable, that had a live analog station-port still connected to it, left it laying on the ground, in a puddle of water. This line called 911 twice within a week.

Example 2: I had an intercom phone at an entrance gate. There was "indoor" cat 5 going to that phone, under-ground, in conduits, but in one of the pull-boxes in the grass, there was a bee-hive. They put honey all over the cable and somehow that honey (or the bees?) got through the jacket of the cable and created the intermittent short-circuit on that line. So my gate-intercom called 911.
 
There is a simple way of stopping the situation phadobas is describing and that is to force everything over to DTMF dialling only. Check command 12, YY=00 and set all analogues to 2.
 
Look in your system timers at what is a valid call for SMDR to report. Some programmers leave this as default. Always set this to the shortest possible value.
 
Thank you all for your input
"phadobas" I saw this all the time with the NEC 2000's but this is the first time I have seen it with the SV8300 I had thought about it though but was not sure if anyone else had seen it on the newer systems.
" thevoipster1" I had preciously shortened to the SMDR but i will be double checking this one again.

"OzzieGeorge" good call on this one I am going to work this one in to test it out I forget that DP is still allowed by default.
 
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