Description
Principle of Operation:
The relay measures the line current from each of the line CTs and if the current exceeds the set threshold, then relay extends a trip signal after an operating time.
The relay’s “operating time” is determined by selecting “definite time” or one of the six “inverse time” characteristics.
Input to sensitive earth fault protection can be derived in two ways:
Residual current derived from three phase current transformers can be used as an input Out put of core balance current transformer (CBCT) having appropriate characteristics can be used as an input.
Input to high impedance restricted earth fault protection will be derived from neutral CT output with external stabilizing resistor.
Phase over current, Earth fault, Sensitive earth fault/Restricted earth fault protections features can be made active or inhibit independently. Inhibition of all protection is not possible
Application:
The relay provides time graded phase and earth fault (2 stage) protection with communication facility.
Ratings
| Current rating ( In ) | 1A / 5A ( Site selectable) |
| Aux. Supply | 1) 20 to 60V DC |
| 2) 80 to 260V AC / DC |
Settings:
| Operating characteristics (Separate for Phase & Earth fault ) |
1) 3.0s Normal Inverse 2) 1.3s Normal Inverse 3) 1.5s Very Inverse 4) 0.8s Extremely Inverse 5) 0.6s Extremely Inverse 6) 13.3s Long Inverse 7) Definite Time |
| Phase OC (IDMT) | 20 to 200% in steps of 5% |
| Phase OC (Def time) | 50 to 500% in steps of 5 % |
| Earth fault (IDMT) | 5 to 80% in steps of 1% |
| Earth fault (Def time) | 5 to 100% in steps of 1% |
| SEF (Def time) | 2 to 80% in steps of 1% |
| TMS (Ph & E/F) | 0.02 to 1.0 in steps of 0.01 |
| Definite time (Ph, E/F & SEF ) | 0 to 25.0s in steps of 0.1s (0 –Instantaneous) |
| Phase Hi-set | 200 to 3200% in steps of 100% |
| Earth fault Hi-set | 50 to 1000% in steps of 50% |
| Hi-set operating time ( Ph & E/F ) |
0 to 500ms in steps of 50ms (0 – Instantaneous) |
| RS232 communication | MODBUS Protocol 9-Pin D at front end |
| RS485 communication | MODBUS Protocol Isolated Rs485 at rear end |
Mechanical Design :
| Weight | 2.5 Kgs.(Approx) |
| Case Size | Fascia 144mm x 144mm depth 232mm |
| Installation | Flush mounting |
| Panel cutout | 138mm x 138mm |
Accuracy:
| Operating value(IDMT) |
105% to 125% |
| Operating value (Def time) |
100% to 115% |
| Hiset operating value |
±5% |
| Drop-off / pick-up | Between 70% to 98% |
| Operating time | ±5% or ±30ms whichever is higher, for 3.0s NI, 1.3s NI.±7% or ±30ms whichever is higher, for 0.8s EI, 0.6s EI,1.5s VI & 13.3s LI characteristics. |
Contact Ratings:
| Trip Contact Make & carry |
1250VA at maximum 10A or 440V AC / 220V DC |
| Break capacity Alarm, Self |
2300VA at maximum 10A or 440V AC / 250V DC |
| supervision contacts | 5A at 24V DC / 230V AC |
Over Load Rating:
| Current input | 2 times rated continuous 20 times rated for 3s 40 times rated for 1s) |
Burden:
| Current input | 0.4VA per phase (Rated 5A) 0.05VA per Phase (Rated 1A) |
| Aux. Supply | Less than 8W (Non operated) Less than 12W (Operated) |
Ordering Information
| Relay | JNC 068 – CALP |
| Communication | First digit C 1-No communication 2-With MODBUS communication over RS 232 & RS 485 |
| Auxiliary supply | Second digit : A 1-20 to 60V DC |
| Nature of Load (on feeder) |
Third digit ; L 1 – Normal Load 2-low Load |
| Protection Element | Fourth digit : P 0 – NONE 1 – With SEF 2 – With REF |
Reviews
There are no reviews yet.