NJBK6 Motor Overload Relay

CHINT NJBK6 series motor overload relay is used to provide overload, phase failure, three-phase current unbalance and locked rotor protection for AC motors with a frequency of AC 50Hz, a rated insulation voltage of below 690V and a rated operational current of 1A~36A that operate continuously or intermittently.

Standards: IEC 60947-4-1

Contact us


  • Features overload given time protection (on/off ), inverse time overload protection, open-phase, three-phase current unbalance protection function;
  • Built-in 4 overload curves are available to meet different occasions;
  • Panel with start and stop buttons, terminal block can be external connected with start and stop buttons with simplified wiring;
  • Auto-start function can open the auto-start function and set the start-up delay. In case of power resumption or reset after power failure, the protector start automatically as per the set auto start delay, free of any human intervention;
  • Fault memory and its indications: In case of motor failure, the indicator displays the fault type, while the bottom row LED flashes and displays the fault code;
  • Mouning mode: screw mounting.


  • Motor protection and control for a variety of drives
  • Application-specific standard configurations resulting in a shorter relay setup and commissioning time
  • Preconfigured solutions for utility distribution and industrial applications



1.Altitude: should not exceed 2000m;
2.Ambient tempeature: -5℃~+40℃, and the average temperature in 24h should not exceed +35℃;
3.Atmospheric conditions: The relative air humidity should not exceed 50% at the maximum temperature of +40℃. The relative humidity may be higher at lower temperatures, for example, the air humidity can be up to 90% at +20℃. Special measures should be taken if condensation occurs on the product occasionally due to temperature variation;
4.Pollution degree: 3;
5.The inclination between the mounting plane and the vertical plane should not exceed ±5°;
6.In non-explosive media that do not contain a sufficient amount of gas or conductive dust to cause metal corrosion or insulation failure;
7.In places with rain and snow protection equipment and not full of vapor;
8.In places where there is no significant shake, impact or vibration;
9.Mounting category: Ⅲ


No. Setting current multiple Operation time Starting conditions Starting conditions
1 1.05 No operation within 2h Cold state +20℃
2 1.2 Operation within 2h Hot Start +20℃
3 1.5 Operation within 2min Hot Start +20℃
4 7.2 2s<Tp≤10s Cold state +20℃