UNZ (Universal Supply Source)


UNZ is modular decentralized supplying system that supplies railways security and protection devices and any other energetic equipment at railway-stations.

UNZ allows according to CSN 34 2600, CSN 342613 and TNZ 34 2606 directives safety supply track circuits at frequencies 75 and 275 Hz that are used by Czech Railways and ZSR.

The real range of operation frequencies is from 0.2 up to 300 Hz with 0.2 steps, that's why UNZ can be used for other railway systems.

UNZ sources can deliver, according to customer's requirements, some or all of following voltages:

  • 3 x 400 V, 50 Hz
  • 2 x 230 V, 75 Hz or 2 x 220 V, 75 Hz
  • 2 x 230 V, 275 Hz or 2 x 220 V, 275 Hz
  • DC voltage 24 V


They can be supplied from:

  • 3 x 400 V, 50 Hz
  • 3 x 400 V, 75 Hz
  • 1ph 400 V that is made from traction mains 25 kV, 50 Hz or 3 kV DC
  • Common distribution network 6 kV, 50 Hz
  • Mobile supply source


Traction mains have much higher voltage variance compared to common distribution networks, but still UNZ allows deliver required voltage.

High-voltage devices and equipments are not part of UNZ.



UNZ combines in one:

  • UPS (Uninterruptible Power Source) using maintenance-free battery that simultaneously eliminates high variance of input voltage
  • Device for 3ph / 50 Hz voltage generation
  • Device for 1ph / 275 Hz voltage generation
  • Device for 1ph / 75 Hz voltage generation


All UNZ components are dimensioned for above mentioned maximum power, only battery capacity, output filters and output transformers are dimensioned later according to capacitive or power steps by customer's request and given location.