Current transformer TZLM-1 (ТЗЛМ-1)

Current transformer TZLM-1 (ТЗЛМ-1)

Zero-phase-sequence current transformer TZLM-1Description

The transformer is intended for powering relay protection circuits from grounding three phase cable separate conductors through transformation of null string currents. The transformer is fixed on the cable with diameter of up to 70 mm (TZLM-1) and up to 100 mm (TZLM-1-1).
The transformers are manufactured in compliance with the standard requirements of GOST 15150 in climatic versions "Y" (temperate) and "T" (tropical) location category 3 and are intended for operation under the following operating conditions:

  • altitude above sea level is not higher than 1000 m;
  • ambient air temperature is given in the table; ambient air humidity is 98% at 25 °C;
  • the environment should be non-explosive, without corrosive steams in concentrations that are likely to destroy metal or insulation (atmosphere type II as to GOST 15150);
  • mounting in any position.

The transformer is patented
Patent Certification №6271 

Table 1. Technical data

Relay type

Used relay scale, A

Actuation device, A

Protection sensibility (primary current, A), no more

 with one transformer

 with serial connection of transformer

 with parallel connection of two transformers

РТ-140/02

0,1...0,2

0,1

8,5

10,2

12,5

РТЗ-51

0,02...0,1

0,03

2,5

3,2

4,8

General view of transformer (drawing)