- ZCT (Zero-Phase Current Transformers): Select from the OTG-N Series (through type) or the OTG-D Series (separate type).
- ZPD (Zero-phase Voltage Detection Unit): Select either a VOC-1MS2 (a split-type set with three VOC-1M units and one K3P-M) or a VOC-3S (integrated type).
VOC-1MS2 Zero-phase Voltage Detection Unit
| Set model No. | Peripheral devices |
| VOC-1MS2 | Zero-phase Voltage Detection Capacitor (VOC-1M) Zero-phase Voltage Detection Capacitor Cap Zero-phase Voltage Transformer (K3P-M) Cable (1 m) |
VOC-1M Ratings and Performance
| Rated voltage | 6,600 VAC |
| Rated frequency | 50/60 Hz |
| Rated capacity | 250 pF |
| Insulation level | 6 A (JEC 1201) |
| Dielectric strength | 22,000 VAC for 1 min (between high-voltage terminal and mounting terminal) 2,000 VAC for 1 min (between low-voltage terminal and mounting terminal) |
| Insulation resistance | 1,000 MΩ min. (between high-voltage terminal and mounting terminal) at 1,000 VDC |
| Impulse withstand voltage |
1.2/50 μs, peak value: 65,000 V (between high-voltage terminal and mounting terminal) |
| Ambient operating temperature |
-20 to 60°C |
| Operation condition | Indoors (in air) |
| Weight | Approx. 550 g (per Unit) |
VOC-3S Zero-phase Voltage Detection Unit
VOC-3S Ratings and Performance
| Rated voltage | 6,600 VAC |
| Rated frequency | 50/60 Hz |
| Output voltage | 7.6 VAC (when 6,600-VAC line is in complete ground fault condition) |
| IO phase angle | 180°±10° |
| Insulation level | 6 A (JEC 1201) |
| Dielectric strength | 22,000 VAC for 1 min (between each high-voltage terminal and case, and between high-voltage terminals) 2,000 VAC for 1 min (between each high-voltage terminal and case) |
| Insulation resistance | 1,000 MΩ min. (between each high-voltage terminal and case, and between high-voltage terminals) at 1,000 VDC 10 MΩ min. (between each high-voltage terminal and case) at 1,000 VDC |
| Impulse withstand voltage |
1.2/50 μs, peak value: 65,000 V (JEC 212)(between high-voltage terminal and case) |
| Ambient operating temperature |
-20 to 60°C |
| Operation condition | Indoors (in air) |
| Weight | Approx. 6.2 kg (per Unit) |
Note: Changing between 50-Hz operation and 60-Hz operation can be achieved through selective connections at output terminals.
Note: The following devices are also available if necessary.
OB Ground Fault Protector
A Ground Fault Protector is required for current compensation when an insulation transformer is used in power-receiving equipment, and the ground current on the power supply side (as viewed from the Zero-phase Voltage Transformer) is insufficient for the sensitivity of the relay.
OB Ratings and Performance
| Model Type |
OB | ||
| For 3,300 V | For 6,600 V | ||
| Circuit voltage | 3,300 V | 6,600 V | |
| Rated voltage | 3,300 /√3 | 6,600 /√3 | |
| Rated frequency | 50/60 Hz | ||
| Capacitance | 0.3 μF x 3 | 0.2 μF x 3 | |
| Compensation current |
50 Hz | 0.54 A | 0.72 A |
| 60 HZ | 0.65 A | 0.86 A | |
| Insulation level | 3 B | 6 B | |
| Dielectric strength | 10,000 VAC for 1 min 30,000 VDC for 10 s |
16,000 VAC for 1 min 45,000 VDC for 10 s |
|
| Operation condition | Indoors, outdoors (in air) | ||
| Weight | Approx. 15 kg | ||
AOF-1N Auxiliary Power Supply Unit
An Auxiliary Power Supply Unit is required when using the K2CA-DO Over Current Relay and K2GS-BT Earth-fault Directional Relay in combination, or when using the K2CA-HC Over Current Relay and K2GS-H Earth-fault Directional Relay in combination.
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