DAK-2 Voltage Converter 3 kV

Traction voltage converter DAK-2 is designed for 3 kV DC conversion to 460 V DC voltage. Its main purpose is to supply Universal Supply Source (USS) and electric heating of railway switches.

Technical Parameters

Power PN 32 to 256 kW
Input Rated DC Voltage U1N 3000 V according to EN 50163
Input Maximal Voltage U1M 3900 V
Input Minimal Voltage U1m 2000 V
Reverse Input Current Ripple f1Z 600 Hz
Output Rated DC Voltage U2N 460 V
Output Maximal Voltage U2M 539 V
Output Minimal Voltage U2m 391 V
Output Rated Current I2N 70 to 556 A
Efficiency h 95 %
Ambient Temperature nA -40 to +40 °C
Mean Time Between Failures (MTBF) tp >30000 h
Overload 1 min
1 h
200 %
130 %
110 %
Auxiliary Voltage (Start, Diagnostic) 230 V 50 Hz

Protection against dangerous touch voltage

Protection of parts without voltage

  • Protection of HV parts against dangerous touch voltage is done by according to standards CSN 34 2600 and CSN 34 1500
  • Protection of LV parts against dangerous touch voltage is done by one of ways described in standard CSN 33 2000 - 4 - 41

Protection of parts under voltage

It is done by coverage and positioning

Protection against overvoltage

Converter is resistant against transients in traction mains or it is automatically switched off during the time when overvoltage exceeds its limits.

During atmospheric failures can be converter's operation broken down, in the last resort (after lighting stroke) can be over-current protection connected - but converter is not damaged.

EMC conditions

EMC regulations are met according to radio-frequency interference standards for industrial environments or according to Czech Railways standards.


DAK-2 is usually installed on the concrete bed next to the connecting place to the reverse rail mains.

DAK-2 and USS should be conducted in such a way that cable connections are minimal and area made of the USS feed line is minimal.


Environments according
to ČSN 33 2000-3:
Outdoor environments with vibration (AA2, AA4, AB2, AC1, AD4, AE4, AG2, AH2, AK1, AL2, AM1, AN2, AP1, AQ1, AR3, AS3, AS1, BA5, BC3, BD1).


Relative air humidity is supposed for outdoor device

Power 32kW: 1000 x 800 x 2000 mm
Power 64kW: 1200 x 1000 x 2000 mm