The ZJJ-4SC DC insulation relay adopts a fully static circuit with a high-sensitivity grounding resistance monitoring and display circuit, which helps users make a quantitative assessment of the reduction of the insulation degree of the DC bus bar, and monitors the grounding resistance of the positive and negative bus bars online in real-time. When the ground insulation drops to the set value, the relay sends out a warning signal.
The relay adopts a full hardware divider operation circuit to directly display the grounding resistance value, and the alarm threshold value is also directly adjusted and displayed on the panel. ZJJ-4SC adopts guide rail installation, with ultra-small size of 115mmX90mmX40mm, dry contact alarm output. The monitoring voltage value can be as wide as 48-1500v and is not affected by the fluctuation of the measured voltage. It is widely used in DC speed regulating motors, solar power generation, and other fields.

Input voltage | DC220V |
Operating voltage range | 100~350V |
Resistance range | 0~1999KΩ |
Short circuit ground current | Max 0.6mA |
Accuracy | 5% |
Alarm setting range | 0~999KΩ |
Return coefficient | 95%~98% @ Rs=50KΩ |
Output contact capacity | DC 220V 0.2A |
AC 250V 2A | |
Power supply | 7~10mA |
Operating temperature | -40~70 |
Dimensions | 115mm x 90mm x 40mm |
* Solar power generation and other fields
* DC or AC/DC main circuits
* UPS systems, battery systems.
* IT systems with high leakage capacitances
* DC charging stations for electric vehicles.




