Automatic telephone exchange. Install

    I would like to submit a note on telephony to the court of the habrasociety. What will it be about? About how the installation of a conventional analog PBX takes place (although not necessarily only an analog one).

    To begin with, I would like to note that not IP-telephony will be considered here, but ordinary analog telephony. Although IP-telephony and strides by leaps and bounds and I completely agree that it is the future. But still, the vast majority of office workers (especially in the regions) are sitting on analog phones. Moreover, in many modern exchanges there are gateways for IP-telephony.

    Some terminology (It is not quite the same as everywhere else (and the standards in particular, but unfortunately I have so once trained, a request strongly not to beat :))
    Point - final device - telephone, fax, modem. In general, a socket where you can stick something.
    Cross  - in one of the directories on telephony “Telephone cross in general is a distribution switching system for office exchanges.”
    Interfloor cross  - in fact, is intermediate between the main (which is connected directly to the PBX) and end points.
    Plinth  - “are used for solderless connection of cross wires and are equipped with contacts, which are of several types: primarily disconnected and non-disconnected.” The most common for small and medium-sized offices are Krone and 110.
    TK  - technical task :)

    Some tool.
    Cold head and clean hands - about clean hands is by no means a metaphor, especially when laying over a false ceiling, the colorful handprints on the ceiling do not impress the customer  Crimping  - it is not strange, but it may not be necessary  Installation tool for terminating and trimming wires  - in common language called clogging, a plinth and a couple more names. Serves for terminating wires in skirtings and sockets. It happens of different types, it is best to take two, one under 110/66 another under Krone.
    Stepladder  - often useful  Punch  - create holes in the walls, sometimes used to create a hole in the floor (ceiling).
    Wiring detector - unfortunately in Russia, there is such a specificity as wiring laid absolutely at unimaginable angles, in absolutely impossible places. So before drilling, you must definitely check the wall.
    Tester  - we use testers from Fluke in our work. We
    also need screwdrivers (Phillips, flat, small and large), side cutters, wire cutters, pliers. Well, we must remember that it is better to take the extra than to run around and look for a hammer (for example)
    Another very useful thing in such things (and not only) is the walkie-talkie. We use Icom F-26 joy stations in the LPD range. Communication is sufficient for our needs.

    Cable - the most diverse (depending on installation). Most often, the number of pairs is divided by street / inner
    Jackie - 6P4C (RJ-11), 8P8C (RJ-45)
    Sockets, keystones - of various variations.
    Skirtings - 110, Krone.
    Cable channels, trays, if you use cobbing, then alabaster or putty :)
    Patch panels, amphenols (TELCO)

    It is written on behalf of a person who, as far as possible , tries to manage a small company engaged in IT outsourcing, additionally involved in the laying of local networks, telephony and other similar things, that is, from mine. Of course, we don’t do everything according to the SCS standards, although efforts are being made closer to the ideal.

    Suppose you are installing a PBX (or not, but you have been asked to help with it, or just want to do it :), and if you don't want to, at least read it). The first thing you need to know from the client is the number of internal phones required, the number of external lines. IMHO - these are the main parameters. Then we find out which room (or building, or a complex of buildings). We begin to ask the client about the additional functions he needs.

    From personal experience: Often people do not even know what they need or what can be done. For example, not many people know the advantages (and some of the existence) of a system telephone, DISA functions (auto secretary), a doorphone controlled from a telephone (which is actually a telephone, only programmed a little differently), conference and speakerphone calls, and many, many more . I also ask the client about the need for IP-telephony, it is better to ask - "How much do you call long-distance?", So he will understand.

    After clarifying the details, we ask the client to prepare a floor plan (very preferably a building plan), print it out and eat it for the client. Now you need to walk (one of those who will do the installation must do it) with the client in the building and mark on the map where the phones will be. Also find out where ATSka will be installed, explaining that you need a separate room or can be combined with a server room. Pay attention to the walls, ceiling (mounted or not), skirting boards, In general, what you need for installation.
    From personal experience: The exact location for the phones themselves is often not indicated (it just appears on the table and you need to say it here!), Because you can use common sense - so that the wire to the phone is less noticeable and especially not get underfoot.

    After inspection and preparation of the plan, TK begins to be developed. It must necessarily contain a list of necessary end-user connection points (with a plan for their connection), cable routes, necessary functionality, and lead times.

    At the same time, we draw up an estimate - cables, connectors, panels, skirtings, automatic telephone exchanges with expansion cards (or without), cross-boxes, etc. Personally, I use the SCS Experts program for work (don’t count it as PR, I just never saw such programs of this level anymore). And quite often it turns out that the cost of one installation can exceed the cost of the telephone exchange by 10-15 times.
    From personal experience: the average cost of one point was approximately $ 30 (telephony only). Apart from the exotic options, when everything is in one room (although there are enough of its own problems) or vice versa there are 5 points, but each in different houses (and this happens)

    If the client signs the statement of work. Then we conclude a contract for the supply and installation. If not, you need to find out what does not suit you, if there are some technical issues (it happens when the client is not special, but you need to build everyone), then you should try to talk to argue your decision. If the issue’s price doesn’t suit you, you can try to explain that there are wholesale prices, you make a margin (I usually speak about 10%) and sell, or pick something in a lower price range (remove any functions, reduce the number of lines).

    From personal experience: Once I got a client buying a PBX with about 100 numbers. After drawing up TK, and then estimates, he refused to cooperate with us. The wording is: “We buy a PBX from you for 50,000 rubles, and you think we need to install another 200,000 thousand, you should pass all the cables for free to us.” Unfortunately, to explain to the client that he was not completely right did not work and we broke up. It is still interesting whether he set himself a telephone exchange or not.

    After all questions have been settled, you can invoice for payment. All changes to the technical requirements will now be decided at the level of directors. With explanations that compilation of TK and budget documentation also cost money.

    Further, the statement of work is given to the chief of the assembly team for signature. Now he will know how and what the installers should do.

    After payment:

    Installation itself begins.

    It is done in approximately the following sequence -

    1. Installers walk around the office, looking closely :)
    2. Take a punch and drill holes in all the places they need (at least this item should be done with a smaller crowd of people)
    3. Then lay the cable channels, trays and so on (with the expectation that it is possible to shove 2 times more cables than it should be according to plan)
    4. The main and floor cross-sections are installed (sometimes a floor cross-section is just a cross-box)
    (the division is conditional, since sometimes there are 8 people on 3 floors, and to allocate a separate cross for each floor, although by standards, sometimes one common thing is done at all. It also happens that there is a call center on some floor, and in this case, there may be several
    crosses ) 5. Trunk lines are laid. We mark each cable, at the ends, and at each floor passage. Routes are usually laid with a 20% margin in line capacity.
    6. From the floor cross cables we scatter cables into cabinets (points). Do not forget to label.
    7.Then 1-2 people go through the points and install sockets. Why not right away? And that would not carry a bunch of different tools.
    8.After that, crossover takes place. Everything is recorded (and almost on video).
    9.Then the PBX is connected and programmed. There are already ways, programs and complexity depend on its brand.
    10.Double run over all points, call. We check the programmed things so that everything works as it should.
    11. The next paragraph is the signing of the “Act of Completed Works”. Exchange of documents, seals and signatures.
    12.PROFFIT !!!

    In the next article I will talk about the practical installation and initial programming of the Panasonic TDA-100 PBX. Constructive criticism, your wishes and suggestions are taken into account :).

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