T3SU (reg. no. 7001-7020) and T3SUCS cars (reg. no. 7021-7292) are variants of the T3 car with the classic equipment with the accelerator designed for the Soviet Union (SU), and other modifications to suit our conditions of operation (SUCS).

The first series was a true "export concurrence", with the max. relay indicator on the panel, a circuit breaker in the fuse box, air intake valve of choice in motor-generator, yellow-green 24 V cabling of the vehicle under the panel, double seats on the right side of the saolon and seats on the back deck with no driver post at the back etc. The installation of the 600 V jumper on front was luckily cancelled in the last minute. With the double seats there was a problem of rack breaking, which was solved by supports and later reconstruction to the usual seats.

The design of the wooden cabin of the car was then also complemented to T3 cars. Depots very quickly complemented through the plexiglass windows of the cab cover grids at first from the two-axle vehicles and later from the newly produced ones. Cars had - in Prague after many years - switch for accelerator waste heat.

Another series following negotiations gradually approached the equipment of original T3 cars. Only the last two series already had disconnector-earthing 600 V and indirect control of fluorescent contactors.

After 1989 the cars were intended for upgrade with the pulse equipment but for financial reasons cheaper serial-parallel connection of traction motors was tested (for the start all in the series, then the circuit switches to the usual connection). There were two versions of connection. For SP2 accelerator divided into two isolated halves could not hold the high induction voltage of motors when switched over and got punched through. Therefore, this type of upgrade was abandoned and only after many years a small part of T3SU cars underwent conversion to T3R.P with IGBT transistors.

Other experimental upgrade for T3R was in 1992-1994 the reconstruction of the registration number 7007 to the thyristor TV8 equipment with GTO thyristors, reg. no. 8200 in central workshops. It was equipped with patterned rubber floor, pop-up windows, information system, electric sandblasts, folding couplers, bogies with dual springing, original motor generator, the anti-slip / skid protection etc.

T3SU7005 was supposed to become the second Prague T3R car. The car upgrade was conducted by ČKD Tatra in 1996 and 1997 but was never finished; the unfinished cabinet was left in the plant and was scrapped in 2002. The T6A5 cabinet was delivered as a compensation, which is used for further reconstruction - T6A5.3, reg. no. 8600 On several vehicles the option of passenger controlled door opening was tested in the 1990´s and gained experiences were capitalized with new T6A5 cars and other upgrades.


Total vehicle length: 15,104 mm
Vehicle height: 3,060 mm
Vehicle width: 2,500 mm
Vehicle weight: 15,810 kg
The maximum number of seats / standing places: 24/138 persons


Tram Repair Plant
U Vozovny 590/6
108 00 Praha 10