Smart switchboard for public lighting

Smart switchboard

for public lighting based on open technologies and the Tecomat Foxtrot 2 system

THOUGHTFUL RECONSTRUCTION OF PUBLIC LIGHTING IN MUNICIPALITIES AND CITIES DOES NOT HAVE TO START WITH A SIMPLE REPLACEMENT OF DISCHARGE LAMPS WITH LED LAMPS SIMPLY BECAUSE THE SUBSIDIES ARE CONDITIONED PRIMARILY BY THE IMPERATIVE OF SAVINGS. AND TODAY, LED TECHNOLOGY IS ASSOCIATED WITH THE ATTRIBUTE OF ENERGY SAVINGS.

A more systematic approach is to start with infrastructure reconstruction. That is, from switching points - public lighting switchboards; from local points spread around the city or village. The company Technology of the Capital City of Prague went in this direction and verifi ed this concept on pilot projects at the beginning of 2020. The following is a very brief description of the solution of one of them. It is based on open data and technologies, secure communications, and the latest generation of the Foxtrot 2 control system from the company Teco a.s.

Among other things, a broadband wireless connection (4G / LTE / 5G) provided by some of the operators can be routed to the switching points and thus create the basic backbone network of the urban IoT. The switch-on point itself can then create its own wireless network in the open unlicensed ISM band (868MHz), through which mesh communication or successive retransmissions can cover the communication of each luminaire connected to the slave outlets. For such a concept, Foxtrot 2 is the ideal basic „building block“ of any modern switchboard.

In such a case, the switchboard can be equipped with on-line secondary measurement of the switching point not only as a whole, but also with detailed measurement on each outlet. By measuring the instantaneous power input and comparing it with the nominal value, it is possible to detect the failure of an individual luminaire, which can be notifi ed by email or SMS warning message or WEB notifi cation to the mobile phone of service staff and timely exchange to avoid complaints

from inhabitants. So the basics of the system are continuous online monitoring of the condition of circuit breakers, contactors, overvoltage protections, indoor and outdoor temperature measurement, outdoor lighting or monitoring of the status of backup batteries, automatic diagnostics of the control system and all its communication lines and switching from automatic to manual mode.

A new and important moment is the remote access to the switchboard. Thanks to Foxtrot 2, which has an integrated LTE modem that allows it to be connected to the Internet anywhere, the situation is simple, and you can use an internal website. For secure, authorized access via any browser, the TecoRoute service can be used - access via a secure https protocol and without a public IP address, or newly via a VPN network. Foxtrot 2 has a state-of-the-art Wireguard VPN integrated. This level of access is suffi cient for municipalities and small towns that do not intend to integrate access to individual public lighting switchboards under a higher unit or into a database system.

Larger cities, on the other hand, can use the standardized MQTT protocol, which is popular in the world of the Internet of Things (IoT) and sometimes synonymous with it, for integration into an existing or newly built centralized technical services dispatch centre. Using this protocol, which is part of the basic equipment of the Foxtrot system, the switch-on point publishes all necessary and required data to the superior database (see the fi gure).

The application program and its web pages in the settings section allow the user to confi gure virtually any parameter, even in the part of controlling the content and frequency of communication of these parameters to the parent database. The operator thus has the system fully in his hands and is not dependent on the supplier in routine operational modifi cations or service.

In the spring of 2020, the concept described above was implemented as part of a pilot project of the company Technology of the Capital City of Prague at seven locations in Prague. Smooth replacement of old switchboards with new and communicating ones from day to day, and continuous operation from the end of April with centralized monitoring at the operator‘s control room confi rm the practicality and reliability of the concept described above.

This project is replicable to other cities and municipalities as it is ready for integration into already operated city information systems. Although it is implemented in an outdoor environment, this concept is applicable to any other consumption point with virtually any number of outlets and power inputs. Inquiries can be directed to Teco a.s.

The concept of wireless communication of the public lighting switch-on point to the superior control room, communication with service staff and communication with each subordinate lighting point. The new Foxtrot 2 is the communication

HTTPS Acces

TecoRoute without public IP address

MQTT Broker

Lte

868 MHz

Switching point switchboard

Extension of wireless communication with individual light poles

Up to 30 × f1 pins

and control center here, and other sensors can be connected via its network in the 868 MHz band, thus naturally expanding the Internet of Things (IoT).

Management view of switching points via a table or map. At fi rst glance, the color of the icons determines the basic states of the switch-on point.

The modern „Smart“ switching point contains

1. Foxtrot CP-2005 control and communication centre with LTE modem for connection to VPN or TecoRoute network. 2. Expansion modules of inputs, outputs 3. Power supply 230 V AC / 24 V DC / with UPS function 4. 24 V DC backup battery 5. 36-channel electricity meter (up to 12 three-phase outlets measured in individual phases) 6. Measurement of the total 3f sampling of switch-on point 7. Measurement of consumption of individual 1f terminals 8. 1f hybrid contactors (switching in 0 - ready for

LED loads with capacitive character of the load) 9. 1f circuit breakers with auxiliary contact 10. Main fuse, main switch, lightning arresters 11. Manual / Automatic - switch 12. Temperature and brightness / twilight sensors 13. Output terminal block of individual directions 14. Switchboard service lighting 15. Door contact