Current transformer TZLK-O5.1 (ТЗЛК-О5.1)

Current transformer TZLK-O5.1 (ТЗЛК-О5.1)

Zero-phase-sequence current transformer TZLKDescription

The transformers are intended for powering relay protection circuits from grounding separate conductors of three phase cable through transformation of null string currents. The transformer in fixed on the cable.
The transformers are manufactured in compliance with the standard requirements of GOST 15150 and GOST 15543.1 in climatic version "O" (generally used) location category 5.1 and are intended for operation under the following operating conditions:

  • ambient air temperature while operation is from minus 50 to plus 55°C;
  • ambient air humidity is 98% at 35 °C;
  • the environment of underground roadways of coal and shale mines;
  • mounting in any position. 

Table 1. Technical data

Parameter Value
Rated voltage, kV
Tes voltage, kV, during one minute
AC current frequency, Hz
Transformer ratio
Weight, kg
One-second thermal current, A
Responsivity (secondary voltage at active load of 1 Ohm) at primary current of 0.25A, no less than, mV
Responsivity of protection in connection with relay type ZZM-1 U 2 "Zero" (primary current)< no more than, A

Minimum seal-in current with relay RTZ-51, A:

regulating point                                    30 mA
                                                        122 mA
with relay RT-140/0.2, A regulating point 100 mA



Current angle error at the active load 1 Ω with respect to primary current, at the primary current 0,25, no more
Voltage on secondary winding terminals "1И1" and "1И2" at the load of 1 Ω while current of 0,04 A at 50 Hz frequency is running at the auxiliary winding "2И1" and "2И2", no less, than, mV
Percentage of harmonics in the secondary current at the load 1Ω at the sinusoidal shaped primary current 0,2 A, no more, %

General view of transformer (drawing)