Is communal paradise accessible to everyone? A story with a sad ending

Hi Habr!

A few days ago I saw an article about installing a weather control system in an apartment building. Having a ReadOnly account, I could not participate in the discussion of the article, so I decided to write my own, with SCADA and regulators, but it will not be as optimistic, and - a spoiler! - will have a sad end.
The weight of the pictures under the cut ~ 1.5 mb.

I am a process control software engineer. Our small but very proud company is engaged in industrial automation in the field of oil refining. I won’t tell how we got into the housing and communal services, I doubt that this story, comparable with the adventure, will be of interest to anyone.

First, we were involved in the installation of heat metering units with the ability to remotely take readings through a GSM modem, later we decided to do weather control of the heat carrier. We considered different options, I will not list the ones we rejected, but settled on the solution offered by the MZTA plant : an automated heat station based on PLC MS8:

This controller buys a small (comparative) price, free development, debugging and scheduling software, communication capabilities and good technical support. The development environment for it is so simple that it seems that the most inveterate humanities are able to figure it out - a kind of FBD, only easier. If someone from the community shows interest, I can do a review, the thing is very interesting. Also, the manufacturer kindly provided us with a blank of the AITP control algorithm. The technological scheme of the weather regulator is as follows:

In short: the coolant comes from the supplier, an electric valve is installed at the entrance to the consumer’s heating system, which is controlled by the PLC. After passing through the building, the coolant returns to AITP, where the pump, with the inverter (frequency converter), again pumps it into the supply pipe. Further, the system includes six temperature sensors - three for measuring the temperature of the coolant (at the "supply" before and after the valve and at the "return") and three for measuring the air temperature (two in the extreme opposite rooms and one on the street). In addition, this also includes two pressure sensors - on the "feed" and "return". And, of course, the heat meter enters there. The appearance of AITP in the photo below:

Now briefly about the principle of operation of automation: based on the measured air temperature in the street, according to the temperature graph, the required temperature of the coolant is calculated. According to PID law, it is controlled by a valve, opening and closing within the range of 0-100%. But if you just close the valve, the pressure in the system will not be enough for the water to circulate freely, so there is a pump in the system that pumps water from the "return" to the "supply". Thanks to the inverter, the pump speed is also regulated according to the PID law, and maintain a given pressure drop. The regulator focuses on street temperature, there is the possibility of correction for room temperatures - one or the middle of the two. In addition, it is possible to set restrictions on the maximum and minimum temperature of the coolant.

If the building has a heat exchanger for preparing hot water, then another circuit with a valve is added to maintain the set temperature and a circulation pump. It is possible to introduce a cold water supply in the system of a booster station, also equipped with an inverter, to maintain a given pressure according to the PID law. In addition, we added functions that are not directly related to the heating point - for example, managing street and entrance lighting on a schedule - anything is possible, there would be a desire!

Each TP was connected to a dispatch system with a single SCADA system. At first, communication was organized through GPRS modems, later we began to gradually transfer to wired channels - the quality of communication in the basements leaves much to be desired. The provider provided us with a private VPN network, invisible from the outside, to which we connected all the controllers and the server. In total, more than forty such regulators were installed.

This is how the SCADA interface looks for one house - there is a heating regulator, a hot water preparation circuit, a cold booster station, and street lighting:

And this is the control room. Sorry for the mess, there was no better photo:

Naturally, the first question that arises for the reader is: how reliable is the system? What happens if the controller fails? What if the lights go out? Will people start to freeze? I answer: Nothing terrible will happen - the valve is equipped with a self-return mechanism and when the power is turned off, it opens 100%, the pump stops, and the coolant enters the house as if there is no control system. The dispatcher receives a notification from SCADA that the connection with the object has disappeared and is taking action. But in practice, I’ll say that over the course of several years, none of the dozens of installed controllers failed, the connection usually disappeared for other reasons, most often, everything was “fixed by itself”, rather quickly. But, despite the high reliability, each circuit, each mechanism can be switched to manual mode on the spot, it is impossible to hope for "maybe".

The next question, of course, is savings. Is the game worth the candle? It all depends on the house itself - in what state of communication, how well the apartments and rooms are insulated. We tried to install regulators in houses after major repairs - the savings in them were maximum. I can’t give real numbers in gigacalories and rubles, because I am far from a working computer - on a business trip - but I can say for sure that in some houses it reaches 50%, compared to previous seasons. In other houses in which cap. there has not been repair for many years, this figure rarely exceeds 10% - large losses affect street heating. The greatest savings come in the warmer months, AITP saves from overflow.

The activity of our company was not limited to automation of heating points - in test mode we built dispatching of elevators in two houses on the basis of the Ob complex . Faults and stops of elevators were detected by the dispatcher before the elevators in the building! Also, voice communication of elevator cabins and a control room was organized. Dispatching system interface:

The next step was the organization of automatic apartment-by-unit accounting of resources (hot, cold water and electricity). In addition, the plans included combining all three areas into one information system based on MasterSCADA , TraceMode or the like - the final decision has not yet been made.

Here again the question arises: where to get the money from? Again with the unfortunate tenants? No, it was supposed to receive financing from the governor’s energy conservation program - I won’t say for sure where I was dealing with financial issues.

But everything that has a beginning will always end. The end of our work in this area came quickly. And this is a very unpleasant story. Habr is not for politics, therefore I do not name any names and places of action, only facts. At the beginning of our activity, the head of the district really liked the initiative, (we got there from its submission), the local press was full of descriptions of our innovations and achievements, the future was bright and cloudless. But suddenly everything changed. I don’t know why the relationship between my leadership and the district administration has deteriorated, but it can be seen from the outside that the issue was selfish. At some point, the persecution began in the same newspapers that had glorified us yesterday, and management companies and municipalities, one after another, began to refuse our services. Regulators have been ineffective, and remote dispatching of elevators is impossible. Six months later, by the summer of 2013, it was all over. Now our company has returned to automation of oil refining and housing and communal services is perceived as a terrible, but, fortunately, dream ended. Currently, most regulators are disabled, and those that operate are serviced by organizations from the regional center (180 km). Elevators from the dispatch system are disabled. Probably better. Communal Paradise is not yet available to everyone.

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