Home automation. The theory and practice of "Smart Homes". Part three

The first part is here .
The second part is here .
Well, that got to the implementation of projects. In this part I will describe the personal experience and difficulties of implementing medium and large home automation projects. This part is long, but in my opinion the most valuable from a practical point of view. In it, I tried to state all the important points and describe the “rakes” I encountered personally.
Details under the cut.

The implementation of practical solutions.

It all starts with the fact that the client comes to us with the phrase "I want!". Most often the customer has already seen something somewhere, or sales managers have told him beautifully beforehand.
1. Terms of Reference.
And here begins the most important part of the project. Drafting of technical specifications. My personal opinion is the following. Having the necessary knowledge, skills and terms of reference, it is quite possible to assemble control panels and dissolve cable routes without project documentation and diagrams, but it is impossible to implement the project as a whole without a technical task signed by the customer. In theory, the customer must write and provide us with the technical specifications for the design, which we correct and jointly sign, as an annex to the contract for the design of the automation system. But this happens only in the country of elves and fairies of "non-traditional". Practically in 100% of cases for the customer, the technical task is written by the performer. In the course of writing, together with the customer, technical details of the future project are formulated. A separate question is the specification of the technical specifications. The “very broad” interpretation of technical solutions can lead to misunderstandings during project implementation. For example, a wording such as: “By a project to provide an embedded wall panel for visualization in room A”, provides an opportunity for fantasies to both the designer and the customer. As a result, the following result can be obtained: the designer lays a huge touch panel at the cost of approximately as a decent car, and the customer needs a wall holder for the iPad and a control application. At the same time, excessive specification of technical specifications, specifying the articles of specific devices and specific technical solutions to be included in the project, binds the designer’s hands and may lead to the technical need (insufficient functionality, inability to be delivered on time) will require the replacement of this equipment, will be at variance with the agreed technical assignment, which is an integral part of the contract for the design of the system.
2. Project documentation.
After the technical moments are stipulated by the technical task, and the financial contract, often begins the longest and most unpleasant part of the project called obtaining initial data. For some reason, most customers are sure that the technical task is sufficient and the countdown of design time begins with the signing of the contract. However, a prerequisite for the commencement of design work should be the receipt of all the initial data specified in the terms of reference and (or) contract (all our design contracts themselves contain this item). Most often, the initial data are obtained in a long time and in torment. This is due to the fact that contractors for the design of adjacent systems are selected by the customer mainly only on price characteristics. It gives a lot of problems. The most painful of them is “crawling walls”. This is when in the process of the “creative thoughts” of the customer and (or) the designer (architect) there is a permanent change in the layouts of the premises, and with them the engineering communications. Very often, this process stops only on the basis of the results of the delivery of the object to the customer, and in “neglected cases” it continues even after the construction is completed. There is only one way to fight this. Get architectural and design projects (and other source data) directly at the customer with the signature “To work” with the date and signature of the customer.
The second serious problem is inconsistent design of adjacent engineering systems. Often the function of the general design is performed by the customer. And he almost always performs it very badly. This leads to the fact that in the process of project implementation it turns out that the functionality specified in our technical specification cannot be implemented due to the fact that the local automation equipment incorporated in the adjacent section does not support certain functions. I will not point the finger, but I can cite as an example the project of a training center of a very large French concern. The task was to make the "most energy efficient" building with the function of centralized control and metering of electrical and thermal energy. As a result, due to the fact that the automation system of the heat point does not support the necessary protocols, and the heat point project does not provide for the installation of additional sensors and heat meters, the task of controlling the heat energy consumption, set at the very beginning in the technical task, was not fulfilled. This problem stems from the fact that, going on about the customer (and we love customers), we started the design, without getting exhaustive baseline data on the projected, adjacent engineering systems. The problem is treated organizationally. Good relations with subcontractors and coordination with the customer of the source data received from subcontractors.
The third problem. Very often, during the design process, the customer tries to change the technical task, arguing that the work on changing the project does not take a lot of time. Here you need to understand whether it is worth making concessions or not, and in each case you need to make a decision, we make it at our own expense or at the expense of the customer. In any case, the rule here is only one. We recall that our TK is an annex to the contract and, accordingly, any changes must somehow be made out preferably with the help of a paper signed by the customer. This is annoying for many, so in most cases we have enough e-mails with explanations of why and naturally we notify the customer that any change, even the smallest (from his point of view), may affect the deadlines for the delivery of project documentation.
3. Installation work.
Most often, installation work begins before the end of the process of preparing project documentation. This usually happens right after the plans for cable runs are ready. And this carries with it a number of serious problems. Usually the documentation at this stage is “raw”, because it is very difficult to accurately track all the nuances that will be visible only at the end of the design process. After all, for a designer a couple of lines on paper and a couple of three mouse clicks on a computer, then for an installer there can be 100 meters of cable routes, of which 50m in fine, 50 m should be attached to the concrete base; 4 holes in concrete walls should be made half a meter. And in general, it may turn out that on the way of laying the final finishing was done. An important part of any installation is supervision. The designer is obliged to visit the site and the point. This is necessary both for high-quality installation and for timely correction of errors in the project. All tracks must be necessarily marked according to the project from 2 sides. Because the amount of cable that is laid in the wall in home automation projects is much higher than in the classical scheme. Marking should be done using tags to cut the cable to move the tag above. If you ignore this important point, before installing the control cabinet you will need to make a “dial” cable. Believe it. This is hellish work. At some sites, the cables were called 3-4 times. Do not ask why. I still do not know the answer, but it was. When carrying out work, the executive documentation should be kept in the form of a fully-fledged copy of the project documentation issued by the foreman of installers, which will be marked and recorded deviations from the project. And they believe the experience is always there. When the installation is completed, the customer or his representative will request a copy of this documentation from you (in most cases this is generally one of the clauses of the installation contract). If it was conducted carefully and in a timely manner, then there will be no problems, if not, then I guarantee you problems with the delivery of the object.
4. Assembly and installation of the control cabinet.
Along with the installation work, one of the most important elements of the project is the assembly of the control cabinet. Practice has shown that the wardrobe cannot be assembled at a high-quality facility with the help of 2.5 electricians from neighboring countries. The cabinet must be assembled and tested by specialists in a workshop that has a sufficient amount of equipment for carrying out these works. Where possible (and possibly not possible), pass-through terminals should be used. This will greatly simplify the decommissioning of outgoing lines at the facility. All conductors inside the cabinet must be labeled. The assembler must provide an executive circuit that may differ from the circuit in the original design. The control cabinet is brought to the site after the final finishing works in the room where it should be installed. The number of control cabinets can be different. At least one, maximum depends on the specific situation and depends on the configuration of the object. To pull a large number of lines of force at one point is time consuming and unprofitable (the cable goes longer), but at the same time, no architect or designer will allow you to arrange a shield in each corner of the house. In any case, this should be discussed with the architect and checked with the plans of related engineering projects at the design stage, otherwise it could cause a serious conflict situation.
5. Installation of lamps, terminals and sensors.
Perhaps the easiest stage in the implementation of the project. This task is performed after finishing the facility. And most often ends after the surrender. But even here there are a couple of pitfalls. Before starting all installation work, I recommend to receive from suppliers or perform all flow charts on installation of luminaires, other terminal devices, sensors and transfer the data of the card to the foreman of dressers. So that they foresee all the necessary holes and niches in the ceiling and walls. Now various kinds of suspended ceilings and suspended ceilings. in stretch ceilings, it is necessary to provide for appropriate fastenings for devices, and in suspended ceilings, either openings or reinforcement frames. lamps and other devices may also have their own installation features. For example, recessed halogen lamps in a metal casing have the peculiarity of expanding as they heat up, and if the finish is wrong, the plaster will begin to crack. Some devices require an in-depth or non-standard installation box. All devices requiring preliminary settings, such as flashing a physical address (KNX), must be pre-configured and labeled according to the project, so that the installer installs a specific device intended for this place at a location.
6. Programming, tuning and commissioning of the system.
This stage begins well before the end of installation. On the basis of the main technical task, the programmer writes his own detailed technical task in which he prescribes all the interfaces and algorithms of the system. If necessary, the TOR is complemented by sketches of device interfaces. It is advisable to prescribe the effect of each sensor and button, so that later there will be no questions about the fact that a device works "incorrectly". This specification is consistent with the customer. Development begins as soon as the project documentation is ready. Of the pitfalls I can note the following. The programmer should be assigned to the project immediately after signing the contract, even though he will actually start working only in a month or two. In fact, the designer should keep the programmer up to date with all the technical solutions taken by him, in order to avoid all the pitfalls associated with programming and configuring certain devices and simplify his work. As these or other modules and parts of the program are ready, the commissioning process at the facility begins. Distributed automation systems can be launched and delivered to the customer in parts. In the literal sense of the room. The last stage of debugging programs is closely related to the delivery of the object. But even after the actual delivery of the object, visits are possible to eliminate errors and fulfill various kinds of customer wishes for adjusting the algorithms and system behavior. All these points need to be negotiated at the stage of concluding an agreement with the customer in the form of a warranty period, after-sales service, as well as specify the conditions and prices for additional work on programming, installation and other issues.
The fourth part will be about the difficulties of integrating automation systems.