Rectifiers have also been employed to convert 60kV AC electricity to 750 V. DC, which are used for trains traction.

A Special power substations had been established at Bonyad-e-Rang, which transforms the 230 kV. AC electricity of the city power network to 2 X 27.5 kV. AC for suburban trains of Line 5.
 

Distribution Networks
The distribution networks consist of 35 rectifying substations for feeding energy to trains, 106 distribution substations for feeding energy to trains, 106 distribution substations for lighting and fixed equipment of stations, Command Control Center and workshops, 850 km. 20 kV cables, 115 km. Traction cables and 155 km. third rail system.
 

• Centralized Traffic Control Center
• Supervisory Control & Data Acquisition System ( SCADA )

1. Centralized Traffic Control System
This system consists of a central section and the facilities in lines. The main part is the traffic control center and its unites established in the technical rooms of the long distance terminal stations.

Controlling traffic of trains and arrange their movement are of the duties of this system.
 

2. Supervisory Control & Data Acquisition System (SCADA)
This system provides continuity of energy feeding to equipment according to priority and equivalent distribution of power.

The equipment of the system consist of a central section and relevant RTUs including SP, ATP, SS and SSP.

SP = Sectioning Post
ATP = Auto Transforming Post
SS = Sub Station
SSP = Sub – Suctioning Post

Telecommunication System
The telecommunication system of the Tehran Metro includes sub-systems as following:

1. Optical Telecommunication Systems & Data Transfers
This system connects all stations and control centers in both sound communication and control data.
 
2. Separate Telephone Network System
Special telephone switching system has been established with respect to the requirement of verbal communication between Metro personnel in all stations and lines to enable communication between them and urban lines.

In addition, in each 50 meters distance, a cross telecommunication line has been established that is known as Party Line and there are also 3 hot line phones, which establish communication with control centers with no need to dialing.
 

3. Dispatching Telephone System
This system provides a direct and easy communication between sensitive technical centers such as technical rooms, power sub-stations and stations' manager rooms.

4. Radio System
This system provides radio communication between control center, train and operation personnel.
Radiation cables that play antenna role are used inside tunnels for radio signals.

5. Closed Circuit Vision System
This system takes pictures form different spots of the station and transmits them to the station manager's room for better control.

6. Central Clock System
This system synchronizes all clocks inside stations and technical centers with the control center.

7. Public Message System
This system broadcasts public messages of stations' officers and control centers.

 

1. The Wayside System
This system consists interlocking system and subway circuits.

The interlocking system establishes path in the pointer establishment point and provides safety of path making.

The Wayside system recognizes position of the train in the lines length, detects and controls train speed with respect to the slope of line, the train direction and its distance with the train in front.

2. The On-board ATP System
This system is mounted in the train control cabin and includes speed meter, receiving antenna for receiving data from line, processing unit and data separation.