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Cellemetry performance question

Discussion in 'Security Alarms' started by W. Rantala, Oct 21, 2003.

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  1. W. Rantala

    W. Rantala Guest

    Has anyone noticed any degradation of reliability with the North
    American Cellemetry data network lately, especially in the
    registration direction? We are currently bringing issues to the
    attention of Numerex/Cellemetry, and would be very interested to know
    if other customers are experiencing problems.

    What we have noticed is a higher degree of message loss attributable
    to server issues at the Cellemetry NOC center, affecting the overall
    reliability of 2 way communication.

    Wayne Rantala
    ZTR Control Systems
  2. thesatguy

    thesatguy Guest

    I have noticed that since local companies offer unlimited internet access
    via your cellphone as a gimmick to get peeps to sign up for cell service, we
    often cannot get through period.

    It used to be when I first installed Uplink units the second you opened the
    Elk Cell box the light would come on and within a second or two the other
    light would start flashing which indicates the transmission is in progress.

    Now, when you open the boxes it is not unusual to wait 40-60 seconds or more
    to get that same response and we have had burglars destroy several units
    that no signals ever were received from even though they cut the telephone
    lines outside of the buildings probably 15 minutes before they ever got
    inside. I have stopped using Uplink because clearly there is a problem but
    the problem seems to be with the locals cell sites being too busy to carry
    traffic. Since we're talking overhnight midnight-5am this makes no sense.
    There is a five second time-delay when the line goes dead until the
    transmitter trips; I test these things all the time and they work every time
    except when people break in. I have added a relay to many installs to fire
    a cell signal every time the alarm system is turned off or on and at the 24
    hour test interval. Yet we still seem to miss signals.

    I had no idea there was a problem somewhere else.
  3. Reg Siemens

    Reg Siemens Guest

    Sending TLM failures via Uplink was specifically NOT recommended by Uplink.
    The reason for this is that the first signal from an Uplink transmits quite
    quickly, subsequent signals take significantly longer as they wait for
    acknowledgement before the next will be sent. In our testing, the first
    signal gets sent typically in less than 20 seconds, however subsequent
    signals are often 2 minutes or more apart. So in our experience it is
    critical that you set it up so that the first signal the Uplink sends is the
    important one i.e. the burg event. Compound your problem with the fact that
    most TLM circuits have a delay built in to avoid nuisance alarms and I can
    understand how you are having systems compromised by thieves that take the
    phone line down prior to the break-in. So while cell service might indeed
    have degraded, perhaps a change in your setup could minimize the impact???

  4. thesatguy

    thesatguy Guest

    What the heck would you use it for if not for line failure?

    Elk Cell Pack has power supply and teleinephone line monitor all-in-one unit
    with telephone line monitor set to trip in 5v seconds. Thats way too fast
    for my liking but the other option is 90 seconds so I use the 5 second

    The first trip should be immediate - I don't care about any additional
    signals - when we get a line fault signal we will poll that panel right then
    to see if the line is really dead. It's the delay caused by the busy cell
    site that is the problem and why in the hell is the cell site busy at 4 am?
    It makes no sense.
  5. A.J.

    A.J. Guest

    It's the design of the technology. First signal goes out immediately, and
    then 2 minutes apart there after for other signals. Take a certain
    communicator for example, trips on 5 zones will take 10 minutes to transmit
    the whole buffer, and if during that time, a fire zone is also trip, the
    fire signal will send on the 12th minute. Scarely huh ?
  6. Reg Siemens

    Reg Siemens Guest

    The purpose is to communicate a burglary event regardless of land-line
    availability. Why do you care if the line goes down? Frankly the REALLY
    important signal is the alarm event. Perhaps your phone lines are more
    reliable than ours around here, but I wouldn't want to be generating a work
    order everytime one of our subscribers phone lines goes down for storm,
    service, malfunction or any number of reasons. Set up the cellemetry backup
    so that it transmits only alarm conditions and you're going to get reliable,
    fast, secured monitoring that works. Saddle the Uplink with TLM
    transmissions and you generate a bunch of nuisance work orders and
    compromise your security when it's an actual alarm event. FWIW that's the
    approach we've taken and it's worked reliably for years.

  7. Reg Siemens

    Reg Siemens Guest

    Thought about this a little more and based on your procedure, I have a
    question. If you get a line fault and then poll the panel to find that the
    line really is dead, what do you do??? Dispatch authorities to bust a phone
    technician doing service in the area??? Send your technician to check it
    out only to waste precious time in the event of an actual B&E???

    Another possibility...are you using the ELK TLM module to shunt Uplink
    transmissions when it doesn't sense a TLM fault? While I'm not familiar
    with the capabilities of the ELK TLM module there are ways to make some TLM
    modules happy while blocking an outgoing call.

  8. thesatguy

    thesatguy Guest

    Why would we care if the line goes down? Because you don't get any signals
    with no phone line.
    Setting up a cellemtry unit to transmit alarm signals is a total waste of
    time cause you don't get any.

    In most cases - at least once a week - burglars cut the phone lines at the
    pole and then cut a hole in the roof directly above the alarm panel and
    proceed to cut every wire they can find. Usually theres around 15 minutes
    before they get into the building after cutting the phone lines. Our runner
    can be there in 20 minutes in many cases.
    Obviously sending the police is a waste of time because of their slow
    response times. It's not unusual to catch peeps on the roof or behind the
    buildings when we get there
  9. thesatguy

    thesatguy Guest

    If you get a line fault and the panel doesn't respond you send a runner if
    the premises is closed - end of story.
    There are no phone guys working on lines at 3am.
    The Elk module can shunt when the phone lines are okay but I have no desire
    to do that. If the lines are okay we will get signals from the panel and
    the Uplink unit and thats fine.
  10. Frank Olson

    Frank Olson Guest

    The information's available on the internet. It's called the "Burglar
    Pages" (like "TheYellow Pages"). It lists stores and commercial premises by
    address and tells you all sorts of neat stuff like what kind of alarm the
    guy has and where the CP is located. :)

    Seriously... I think they call it "casing the joint". It doesn't take
    much. I had to replace a proximity reader at the side entrance to a
    building this morning. Some nut figured that if he smashed the reader with
    a rock the door would "magically" open. The reader's installed on a
    concrete wall with the wires terminating in a tampered box located on the
    back wall of a small corner grocery store in the building.

    I walked up to the store's only counter carrying my tool belt and a small
    cardboard box (with the new reader inside) and simply told the person that I
    was working on the access control system for the building and needed to get
    to the wires at the back of her store. She waved me through and it struck
    me that with the way I was holding my belt and the carton there wasn't any
    way for her to see my ID badge. After I finished my job, I went up to her
    and told her that she should be a little more cautious next time and ask to
    see ID before letting someone go into the more sensitive areas of her store
    (her alarm control panel, telephone connections, and video surveillance
    equipment were all back in the room I was working in). She basically
    allowed a complete stranger into the back of her store because I looked like
    a "worker".

    The one question that begs to be answered... Should I go back and help
    myself to those delicious looking carrot and blueberry muffins she had
    cooling off in a rack back there?? :)
  11. Jackcsg

    Jackcsg Guest

    Actually....Sounds allot like downtown Baltimore, or even DC. I'm serious. I
    don't think this thought pattern would actually work in high crime city. Out
    in the sticks maybe where tree limbs fall on Telco lines, but the City? Land
    lines are faster than 3rd party wireless, why wouldn't you use land first,
    with wireless back-up? Didn't AlarmNet go down recently? Why would you use
    third party wireless? I would use a standard cellular package long before
    Uplink, or AlarmNet. Too Sloooow......

  12. Reg Siemens

    Reg Siemens Guest

    Why would we care if the line goes down? Because you don't get any
    Maybe I'm missing something here but with a properly configured Uplink, you
    do get the alarm signal without the phone line. This is precisely the
    reason for the Uplink.
    If your subscribers premise (or what's in it) is that desireable and they go
    to these lengths to case your installs, then wouldn't you ensure that the
    panel and Uplink is in a protected area that they can't get to without
    tripping a zone well in advance of them being able to compromise the Uplink.
    Our installations will generate an alarm if wires are cut between the panel
    and the Uplink. The only hope would be that they get inside the Uplink box
    and power it down before the signal is sent...virtually impossible with a
    properly secured control panel/Uplink location.

    My point is that with Cellemetry and the limitations of the network you need
    to design your installation so that the important signals get sent first.
    In my mind a burglary or fire signal is a lot more important than a TLM
    failure which may or may not be an actual alarm event.

    Reg Siemens
  13. Chuck

    Chuck Guest

    This type of transmitter is used with battery operated RF sensors which are
    independent of AC power.
  14. Reg Siemens

    Reg Siemens Guest

    This type of transmitter is used with battery operated RF sensors which
    Now I'm REALLY confused...I have no idea what this has to do with the

  15. Spike

    Spike Guest

    What is a standard cellular package? I thought uplink and alarmnet were
  16. Spike wrote
    Like a Telguard classic, the original cell backup technology requiring a
    cell #, and a lot more expensive. They send signals over the cell network
    like a normal cell call. Can be used for voice, fax, etc.too.

    Uplink is a cellemetry unit, like the Skyroute and Telguard Databurst,
    sending short data bursts using the cellular control channel. The unit is
    less expensive, and no cell account is necessary. The signals are processed
    by their c/s, and forwarded to your c/s.
  17. Jackcsg

    Jackcsg Guest

    I didn't say cheaper. Just Faster. And without the hands of Ademco
    (Honeywell), or Uplink (GE?). But if you like a cheaper, slower, and paying
    a third party ...go with it. It's only one persons opinion. I realize for
    some it's the only option they can think of...

  18. Jackcsg wrote
    No need to get your panties in a twist. He asked for an explanation. I've
    used both cell backup and cellemetry units. As for the third party, what do
    you call the cell service provider, a partner?

  19. Jackcsg

    Jackcsg Guest

    Sorry, I lost count. 4th Party. I'm not disgruntle. And I don't think the
    Telco receives my signals and re-transmits back to me, nor do I mind if they
    use other companies switches to get it to me. I'm more of the Grade "AA"
    type. But as I said, just an opinion. Chill fly

  20. Spike

    Spike Guest

    oooooh yah, now I remember... one uses the voice and the other the control
    channel, thanks Jack.
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