Voltage detectors for urban public transportation (trolleybus / tramway) – DTTU type



DTTu-Tb and DTTU-Tv voltage detectors for power installations of interior and exterior urban transportation installations (trolleybus/tramway), with constant voltage of 825 V are warning equipment for the maintenance and operating personnel on the existence of the electric shock hazard, by the optical and acoustic indication of voltage presence. Optical warning is made with intermittent red signals (for reversed polarity) or green (for normal polarity), also visible in strong ambient lighting conditions. Acoustic warning is triggered by intermittent signals with an intensity of 69 dB (A). Both before and after each use, by the push of the test button and the triggering of signals, the detector functionality will be performed (confirming that the battery is in good condition and the electronic circuits are in proper condition).

DTTU-Tb and DTTU-Tv voltage detectors are used in dry weather conditions.

The DTTU-Tb detector for trolleybus includes two insulating sticks (which include detection components) which allow the detection of voltage presence on the two power contact lines of trolleybuses. This tape of detector can also be used in switch boxes (injection points) and in power distribution stations.

The DTTU-Tv detector for tramway includes an insulating stick (which includes the detection components) which is connected, by means of an 8-meter insulated earthing cable, to an alligator clip which can be attached to the rolling track (rail).

Technical characteristics


Maximum operating voltage (V c.c.)


Intermittent signalling, optical and acoustic, in bipolar connection for voltage rates higher than (V c.c.)

130 ± 20

Test voltage for the inspection of dielectric rigidity (V/1min)



9 V battery type 6LR61

Operating temperature range (0C)

-25 …+55

Protection class provided by the housing

IP 20

Weight DTTU Tb / DTTU Tv (kg)

1,35 / 1,19

Voltage detector stick length (cm) 67

Exista 2 tipuri constructive de detectoare:

  • DTTU Tb – pentru rețele electrice pentru troleibuze;
  • DTTU Tv – pentru rețele electrice pentru tramvaie;