Protective resistors RZ1 for KRU

Protective resistors RZ1 for KRU (switchgear and control gear) are used for neutral grounding in 3-6-10 kV networks that enables overvoltage limitation at single arcing ground faults, ferroresonance elimination and relay selectivity.


Technical specifications


Rated resistance
(Ohm)
Place of installationOperating duty under rated current flowTypesClimatic modificationLife time
from 50 to 1500switchgear and control gear (KRU) compartmentsshort-timeA – protective resistor elements (PRE) are organized in two rows in one level.

B – PRE are organized in two levels in one row
UHL and T
2nd and 3rd category
GOST -15150
not less than 30 years

Notes:

UHL and T, as well as 2nd and 3rd arrangement categories mean:

UHL – operation in cold temperate climate;

T – operation in tropical climate;

2nd arrangement category – outdoor installation under the shed, or indoor installation under the conditions similar to outdoor installation.

3rd arrangement category – indoor installation.



Resistors with required rated voltage, rated resistance, climatic modification and dimensions can be manufactured on request.



Major parts of the resistor

  • Protective resistor elements (PRE), Technical Specifications 3414-005-11840528;
  • Mechanical elements;
  • Electrical insulation elements (base insulators, insulation plates).


Designation of the protective resistor RZ1


RZ1 - A - B - C - D


RZ1 - type of a protective resistor

A - Rated resistance, Ohm

B - Rated voltage, kV

C - Type

D - Climatic modification, arrangement category in accordance with GOST-15150



Main characteristics of protective resistors


Type of a resistorRated system voltage
(Urated sys, kV)
Rated resistor voltage
(Urated RZ1, kV)
Rated resistor current
(A)
Rated operating time
(с)
Rated resistance
(Rrated, Ohm)
Resistor current
1 hourcontinious
RZ1-50-3-A31,7334,633506,55
RZ1-100-3-A31,7317,3651004,63,6
RZ1-150-3-A31,7311,61001503,72,9
RZ1-100-6-A63,4634,634,61004,63,6
RZ1-200-6-A63,4617,3332003,22,5
RZ1-300-6-A63,4611,6503002,72,1
RZ1-400-6-A63,468,7654002,31,8
RZ1-500-6-A63,466,9805002,11,6
RZ1-120-10-A105,7748,11012053,9
RZ1-150-10-A105,7738,5121504,53,5
RZ1-200-10-A105,7728,9172003,93
RZ1-300-10-A105,7719,3253003,22,5
RZ1-360-10-A105,7716313602,92,2
RZ1-500-10-A105,7711,6435002,51,9
RZ1-1000-10-A105,775,88510001,71,3
RZ1-1500-10-A105,773,912015001,41,1

Main characteristics of Type A resistors given in the table can be applied to Type B resistors.



Example of the request when ordering


Protective resistor RZ1 for neutral grounding with a resistance 150 ± 10 % Ohm, to be installed in the system with rated voltage 10 kV, type A, having climatic modification UHL, and 2nd arrangement category in accordance with GOST 15150.


RZ1 – 150 – 10 – A – UHL2


Notes:

UHL2 means:

UHL – operation in cold temperate climate;

2 – outdoor installation under the shed, or indoor installation under the conditions similar to outdoor installation.



The main electrical circuit of the resistor consists of in-series PRE in 2 parallel circuits.


Protective resistor RZ1 Type A

Figure 1 – Protective resistor RZ1 Type A



Protective resistor RZ1 Type B

Figure 2 – Protective resistor RZ1 Type B