A.A. Alexandrov, technical director, Russian Monitoring Systems LLC,
V.L. Pereverzev, general manager, CJSC "St. Petersburg Institute of Thermal Power Engineering", St. Petersburg

Currently in Russia, when creating new heat networks of ductless installation (i.e. laid directly into the ground), regulatory documents require the use of steel pipes with industrial thermal insulation made of polyurethane foam (PPU) in a polyethylene shell, equipped with conductors of an online operational remote control system (SRC) dampening the insulation. Their use is aimed at increasing the efficiency and reliability of heating networks and is based on technologies from foreign companies. The technology includes diagnostics, which consists of determining changes in electrical resistance when moisture appears in the polyurethane foam insulation between the pipe and the signal conductor laid along the entire pipeline, and localizing the place of moisture using the location method.

Such diagnostics of heat pipelines makes it possible to detect defects that arise during construction and operation and to localize the places of their occurrence.

Detection and localization of defects can be done using special devices three ways.

1. A portable detector to determine the presence and type of defect (frequency - once every 2 weeks). A portable locator for localizing the location of the defect (frequency - based on the results of measurements with a detector).

2. A stationary detector to determine the presence and type of defect (frequency - constantly 24 hours a day). A portable locator for localizing the location of the defect (frequency - based on the results of the detector triggering, taking into account the scheduled time of arrival of the operator with the locator).

3. A stationary locator to determine the presence and type of defect with simultaneous localization and recording of the place of its occurrence (frequency - probing pulses once every 4 minutes (continuously 24 hours a day)).

Currently in Russia, according to SP 41-105-2002, only the first two are used

a method for determining defects in heating networks in polyurethane foam insulation equipped with UEC conductors. The effectiveness of these methods raises many questions among specialists servicing heating networks, and localization of defect locations using portable locators turns into a labor-intensive operation that does not always lead to correct results. To determine the reason for the low efficiency of existing UEC systems in Russia, a study was carried out comparative analysis principles for constructing imported and domestic SODC, from which the main fundamental differences can be identified:

Absence in requirements regulatory documents compliance with the parameter - complex resistance (impedance) of the polyurethane foam pipe with UEC as an electrical element;

Failure to maintain distance from metal surface element to UEC conductors in pipes and fittings (moreover, the standards establish a variable distance parameter - from 10 to 25 mm);

Lack of devices for coordinating the interrogation line of UEC conductors with locators (reflectometers);

The use of NYM type cables with a high attenuation coefficient of the probing pulse for connecting conductors of UEC pipelines and terminals.

To determine effective ways searching for insulation defects in pre-insulated PPU pipelines, specialists from RMS LLC, SPb ITE CJSC and State Unitary Enterprise TEK SPb tested various interrogation lines of the UEC system (using NYM cable, coaxial cable and various reflectometers) on full-scale model pipeline with reproduction of typical insulation defects.

On the territory of the EAP branch of the State Unitary Enterprise TEK SPb, a section of the polyurethane foam pipeline of the heating network with a nominal diameter of Du57 was installed using shaped products, a bellows compensator and an end element (Fig. 1, photo 1).

To model defective sections of the heating network, unsealed joints with tin gutters were left on the model (photo 2). The remaining joints are made by pouring foaming components using heat-shrinkable sleeves.

When installing the ODK system in accordance with SP 41-105-2002 (NYM type cable), a 10-meter cable from the reflectometer connection point to the pipeline and a 5-meter cable at the intermediate end element were used.

Installation of the UEC system according to EMS (ABB) technology (using a connecting coaxial cable and matching transformers of the “connecting wire - signal conductor” line) was carried out using a 10-meter coaxial cable from the reflectometer connection point to the pipeline (photo 3).

To reduce losses in the interrogation line, the reflectometer was connected to the cable using coaxial fittings.

The measurements were carried out with reflectometers REIS-105 and mTDR-007 (taking reflectograms) when modeling the most likely types of defects in the heating network: break, short circuit of the conductor to the pipe, single and double wetting of the insulation (in different places).

As part of this experiment, the possibilities of combined use various cables when installing the interrogation line of signal conductors SODK (presence of a pass-through terminal) in the following sequence: coaxial cable - conductor ODK - NYM cable - conductor ODK with a break in the conductors at the end of the interrogation line.

As a result of the tests and measurements, the following conclusions can be drawn.

1. The attenuation of the probing pulse in a NYM type cable (Fig. 2b) is several times higher than in a coaxial cable (Fig. 2a). This reduces the length of the surveyed area, limiting effective application locator in areas from camera to camera (150-200 m).

2. Due to the large power losses of the probing pulse, when it passes through the NYM cable, it is necessary to increase its energy by increasing the pulse duration, which leads to a decrease in the accuracy of determining the distance to the location of the pipeline defect.

3. The absence of matching elements at the “cable-pipe” and “pipe-cable” transitions leads to a change in the shape of the reflected pulses, smoothes out their fronts and reduces the accuracy of determining the location of the insulation defect (Fig. 3).

Russian pipes in PPU insulation have different wave properties and parameters from imported ones. The complex electrical resistance (impedance) of pipes and fittings in practice varies from 267 to 361 Ohms (ABB pipes have an impedance of 211 Ohms), therefore the use of foreign matching devices on our pipes is impossible (RMS LLC has developed matching devices for PU foam pipes manufactured according to Russian standards, there is a positive experience of them practical application on real objects).

This point of conclusions deserves special attention in view of its importance for the operation of the SODS.

The spread of impedance for different pipe elements leads to variations in the so-called shortening coefficient for these pipe elements. As is known, measurements are carried out at one shortening coefficient common to the entire pipeline. Thus, having sections along the pipeline with different coefficients shortening, we will get a discrepancy between the measured electrical parameters and the actual physical parameters of the pipelines, and the discrepancy will be greater the longer the pipeline and the more fittings on it (in practice, the discrepancy reaches up to 5 m on a 100-meter section of the pipeline).

For quality design executive documentation According to SODK, it is necessary to monitor not only the insulation resistance and ohmic resistance of the conductor loop, but also measure the shortening coefficient of each mounted pipe element using a reflectometer, recording the measurement results on the as-built diagram of the pipeline. Otherwise, errors when searching for broken conductors and dampening of insulation will lead to an increase in production costs repair work due to a significant increase in the volume of excavation and restoration work.

The lack of impedance standardization allows unscrupulous manufacturers to use varnished copper winding wire as UDC conductors when producing PU-insulated pipes. This allows you to obtain excellent electrical characteristics during installation and a “perpetually serviceable” pipeline, regardless of any moisture insulation. The UEC system, in this case, is a useless, fake application.

Since impedance depends on the dielectric constant of the medium and the distance from the pipe to the conductor, the use of non-standard pipe production methods leads, as a rule, to an increase in impedance and, as a consequence, the shortening coefficient of the pipe element. Impedance standardization would make it difficult for low-quality pipes to enter the market.

5. The use of NYM cables as a communication line between the locator and the PPU pipeline with SODC, as well as as connectors between different sections of pipelines, completely eliminates the use of stationary specialized fault locators (Fig. 4) and does not allow considering the heating network as an object of automation and dispatching, leaving significant costs for linemen and service personnel (Table 1).

6. Application on one controlled section of the pipeline various types connection cables are ineffective.

The most effective are UEC systems based on the use of coaxial cables with matching devices. Such UEC systems are fully compatible with monitoring devices for PPU pipe conductors (the use of which is prescribed by SP 41-105-2002) and can significantly increase the efficiency of their use.

The use of coaxial communication cables between pipelines will open up the possibility of using specialized stationary fault locators for heating networks. Which, in turn, will allow:

Subsequently unite local UEC systems into a single network with the necessary hierarchy;

Display the status of local SDCS at the central control center, indicating the specific location of the network defect (an example of the implementation of such a system is the experience of the State Unitary Enterprise "Fuel and Energy Complex of St. Petersburg");

Promptly take measures to eliminate defects in initial stage their occurrence;

Reduce operating costs of UEC systems (Table 1);

Save significant money on emergency repairs heating networks (Table 2);

Increase the reliability of networks by reducing emergency outages;

Receive objective information about defects and the state of thermal and waterproofing on the heating network by eliminating the influence of subjective human factor in these kinds of issues.

In conclusion, it should be noted that the UEC pipeline system only at first glance seems simple and even primitive in installation. Majority construction organizations they trust the installation of ODS to ordinary electricians, who install ODS like ordinary lighting networks or underground cable installations. As a result, instead of effective remedy control of organizations operating heating networks, they receive a useless application to the heating network.

It should also be noted that properly installed UEC systems make it possible to realize all the advantages of pipelines with polyurethane foam insulation, in particular, to automate as much as possible the search for places of moisture and damage to pipeline insulation, and to increase the accuracy of identifying these places. Pipelines with other types of insulation (APb, PPM, etc.) in principle do not have similar advantages.

Installation of ODS should be carried out by professional organizations that understand all the subtleties and nuances in detecting defects using reflectometers, having necessary equipment, practical experience construction and adjustment of systems. Only professionals are able to create effectively working systems - SODK is no exception to this rule.

Literature

1. SP 41-105-2002. Design and construction of ductless heating networks made of steel pipes with industrial thermal insulation made of polyurethane foam in a polyethylene shell.

2. SNiP 41-02-2003. Heat networks.

3. Slepchenok V.S. Experience in operating a municipal heat and power plant. Uch. manual - St. Petersburg, PEIpk, 2003, 185 p.

The work process requires discipline and order. But how to control the working staff without violating personal boundaries, without scaring off employees and getting benefits?

In this article, we will try to figure out what problems managers have in the absence of control, how to control employees, and what mistakes managers make.

1. Lack of control

Problems that a company faces in the absence of control:

• Being late for work; frequent smoking breaks and tea drinking;
• Poor quality work;
• Employees miss deadlines for completing work;
• Low productivity of both one employee and the entire staff;
• Lack of a clear daily routine - working hours, lunch, conferences, meetings.

2. How to control employees

We identify three common methods of monitoring employees:

• Log books
• Video surveillance
• Control programs

Log books

A simple and inexpensive control method. How it works: a log is kept, which records the time of arrival and departure of the employee. Using this control method, the manager receives information about whether the employee is late or not, how often he leaves workplace on personal matters and when leaving work. The disadvantage of this method of control is that the manager will not be able to know whether he is solving problems during working hours.

Video surveillance

A common method of personnel control. How it works: a video camera records the arrival and departure of an employee, his stay in the office and at his workplace. But this method will not work effectively if the employee works at a computer. The camera will not be able to record whether he is busy with work tasks, reading the news or playing solitaire.

Remote monitoring programs

Popular control method. The advantage of such programs is that they are installed on work computers, record all work and non-work information and transmit it to the manager. This type of control helps to obtain information about when an employee is present/absent at work, what he is doing, what tasks he is solving and how much time is spent on his breaks and coffee.

3. Personnel control mistakes that managers make

The control method chosen by the manager, if applied incorrectly, can lead to negative consequences.

Four classic control mistakes that managers make:

• Incomprehensible control. The manager checks his subordinates, but does not understand the content of the work process at all.

For example, a manager will not be able to control technical process On their own, a lawyer will not be able to check the work of an accountant, and a programmer will not be able to check the work of an editor. In this case, it is better to entrust the control to a specialist in this field.

• Control that goes into conflict situations. The manager controls the process, but only notices the employee’s mistakes and points them out to him as soon as possible? None normal person He won’t stand it if you just “slap” him. Control should be systematic, not frightening and oppressive.
• Hidden control, which becomes explicit when violations are detected. If a manager installs a control system secretly, then at the first mistake you should not “jump out from behind the bushes” shouting “Aha!!! Gotcha! Such “pop-ups” can only increase the negative reaction of the employee and the whole team. Having learned about hidden surveillance, workers will still worry and try to do the job efficiently. And if the manager notices blatant violations in work, you can always discuss it.
• Formal control is control without concrete actions and requirements for the employee.

For example, when the head of a department entrusts a task to a manager and says, “Look at me, I’ll control everything,” but in practice does nothing. Then the manager understands that his work is not being checked and he can cheat. Such lack of control negatively affects the work of not only the department, but the entire company.

Conclusion

Proper organization of control over employees will help solve problems with discipline, identify flaws in the work process and set the team up for productive work.

Country house built - next step monitor and control electronics in your home from anywhere in the world. Anyone who has already wondered how to do this knows that inexpensive and simple solutions not on the market. But I carefully studied this issue and found a solution in order to not only receive real-time video broadcast, but also have information about temperature/humidity from wireless sensors installed in different places country house. The sensors also have shock sensors, which allows them to be used as part of a security system. In this case, the connection to the Internet is carried out using an ordinary 3G modem!

So, let's go!

It seems so complicated - I installed a 3G modem in a country house, configured DDNS and it’s done! But no. Mobile operators are very cunning and will not miss an opportunity to make money. The whole problem lies in the “gray” IP address that is issued when connecting to the Internet. I won’t go into technical details, but you will never get remote access from the Internet to a local network in your life. Mobile operators offer the service of a real IP address for 100-150 rubles per month and this is not such a critical amount, but there is one BUT: when using this service, traffic is billed per megabyte at rates of approximately 10 rubles per megabyte! No traffic packages are valid.

There is another option to get remote access: to set up a VPN tunnel between the local network in a city apartment and country house. This will require reflashing the router in the apartment, setting up a VPN server on it, and also purchasing a real IP address service from a city provider. After this, you will be able to remotely connect to your apartment local network, which will be connected to a country house. There are no other solutions.

But if you can’t get remote access to the local network using a 3G modem, you need to look for another solution. Namely: so that the devices that we need to access work through the developer’s public server. That is, devices located behind a 3G modem themselves upload data to a server on the Internet, and we will already connect to this service.

2. A budget option for the Internet for a country house looks exactly like this. The Asus RT-N10U router costs 800 rubles and supports USB 3G modems out of the box. It only has one antenna, so maximum speed on the 802.11n network - 150 Mbit. He's like the rest electronic devices connected via a UPS in case of power outages (energy reserve is sufficient for a day battery life). Where to get internet from? I have no particular desire to advertise MTS, but they are the only ones who offer real unlimited traffic in the Moscow region for only 600 rubles per month. True, they also had to try to deceive them - in the middle of the month they suddenly decided to write off not only 600 rubles monthly, but also 24 rubles per day. As a result, by the time of the next monthly payment, there was not enough money in the account to renew and I was left without internet. On the good side, the support service admitted their mistake (surprisingly!) and turned on the Internet for the next month for free (in fact, taking into account illegal write-offs - half the price). Internet speed during the day is 3-4 Mbit for receiving and 1-2 Mbit for sending. At night, the reception speed jumps to 7-8 Mbit. The cost of the 3G modem was 100 rubles (700 rubles total cost including the fee for the first month of Internet). No other mobile operator offers unlimited Internet in the Moscow region for this money.

3. Let's start with video surveillance. Let's take a camera from the Chinese manufacturer Harex. This camera is notable for the fact that it works through the Chinese video broadcast service NVSIP. The company produces only wired (Ethernet) cameras; Wifi is not even available as an option. The cost of the camera is 1000 rubles, and the power supply costs another 200 rubles. Setting up the camera is a little non-trivial; for these purposes you need software that exists exclusively for Windows. The camera is already registered with the NVSIP service by default, and you must go into the settings and change the standard password.

4. The NVSIP website itself also works only in Internet Explorer, but this is not important to us because iOS and Android have their own applications. As you might guess, streaming to mobile devices comes at a resolution much lower than 720p, but is quite sufficient for viewing details. Below are real screenshots from the phone screen. There was a small problem with the infrared illumination of the camera - when the camera was installed as in the photograph (this is a temporary solution), the infrared illumination reflected from the white edges of the body and illuminated the entire frame. In reality, IR illumination penetrates 15-20 meters in complete darkness. The camera can be purchased on Aliexpress (http://www.aliexpress.com/store/609704).

The system is easily complemented with other cameras, and archived video is recorded on a computer running the IPClient application. 1200 rubles per camera is an excellent price. Live video can be accessed from anywhere in the world.

5. Let's move on. Remote monitoring and control system - Wireless Sensor Tags (http://wirelesstag.net). These are a variety of wireless sensors powered by a CR2032 battery, which transmit controlled parameters to their own base via a radio channel. In due time, the base connects via Ethernet to a router with the Internet and uploads all the data to the service website. Basic functions include recording temperature, humidity, rotation angle, opening, water leakage, movement, etc. Remote access is possible through a website or mobile device application. Device developers in at the moment We are creating our own controlled thermostat, as well as integration with the Nest thermostat. This will allow you to remotely turn on/off heating and ventilation.

6. Basic wireless sensor. Measures temperature, humidity and inclination angle. It also has a built-in LED and beeper, which allows you to use it to find lost items. Inside there is a CR2032 battery, which is enough for a year of operation at standard settings for transmitter power (distance up to 60 meters from the base) and data update frequency (every 15 minutes).

7. The leak sensor looks like this. It does not have an LED or beeper. As the manufacturer writes, the sensors themselves are not sealed and are not protected from water; this should be taken into account when placing them. The range also includes motion and opening sensors.

All this was invented in America, the device is unique, there are virtually no alternatives on the market.

8. And here is the main base. Connects to power via USB and via Ethernet to the network. It is registered on the server by its serial number. An interesting observation is that the communication speed over twisted pair cable is 10 Mbit, but why more? The base has operation indicators: communication with sensors, communication with the server, reception, transmission, error.

9. Kumostat mobile application for iOS. The writing is a little crooked and sometimes glitchy, but it is updated regularly. The main screen shows all sensors registered on the base (you can take a photo of each directly in the application for easy identification) and the parameters registered by them: temperature, humidity, time from last update, signal level and security status. If an event occurs, a Push notification is instantly sent to the user’s device (several mobile devices can be registered in the system for one account).

10. Here are some application screens. The first is a list of all events in chronological order. Next are two screens for a specific sensor. The number of customizable parameters is amazing. For example, you can set a controlled temperature range, and if the temperature gets lower or higher, you can set instant notifications by email, push notification or even posting a tweet! And the coolest thing is the graphs of parameter changes for each day. It's incredibly fascinating to watch how the temperature/humidity changes throughout the day.

11. This is what the web interface looks like. Even more functionality than mobile application. As you can see, I have 4 sensors: on front door, under the bathroom, in the kitchen and in the well. In the future, I plan to install a controlled thermostat and remotely control the operation of the air source heat pump. Also, the system is simply supplemented with perimeter control sensors and we get a full-fledged security alarm (I won’t talk about this for obvious reasons - you’ll figure it out for yourself).

12. Graphs of temperature changes for 6 days. The system apparently stores all data from the moment it is turned on. It’s especially fascinating to watch the temperature change in the well (while the sensor is hanging at a depth of 1 meter from the ground, I plan to hang it deeper).

13. Humidity change graphs simply blow your mind. True, pay attention to the scale of the vertical scale - it turns out that everything is not so scary. In a good way, they need to be calibrated, but I have not yet found a reference hygrometer.

14. The number of settings is amazing. You can even change the operating frequency and data transfer rate between the base and sensors. The service also allows you to use scripts to automate actions and use such interesting things as Geofence - disarming / arming when you are with your mobile device find yourself within a set radius of the object. Serious vulnerabilities include lack of password encryption account. When you recover your password, it will be sent to you in unencrypted form.

15. How much does it cost? For $25 a universal wireless tag and $65 for a base. Delivery to Russia will also cost $18. Everything in the photo cost $170. Considering that there are no alternatives on the market at all, and trying to make such a device yourself will run into the problem of a “gray” IP address for a 3G modem, I cannot say that it is very expensive.

More detailed information about tags, see the official website -