



Key Features
- Low Power Consumption
- Built-in High-Frequency Noise Filter
- Internal Blanking Circuit
- High-Gain Differential Amplifier Circuit
- Minimum 100 μA Output Current for SCR Drive
- Built-in Thyristor
- High Noise Immunity and Surge Margin
Applications
- Residential Earth Leakage Circuit Breakers (ELCBs)
NS-COB
In electrical protection devices such as earth leakage circuit breakers, it is important to quickly and reliably detect leakage currents caused by insulation faults or electrical failures. In particular, reliable leakage current detection technology is required to minimize false operation caused by external noise or transient abnormal signals while ensuring stable tripping when actual leakage current occurs.
COBON TECH’s NS-COB is an integrated semiconductor circuit incorporating an amplifier circuit and a thyristor for high-speed earth leakage circuit breakers. It precisely amplifies and processes leakage current signals detected by a Zero-Phase Current Transformer (ZCT) and drives the built-in thyristor. It integrates a differential amplifier, time-delay circuit, latch circuit, and precision reference voltage circuit. In addition, a high-frequency noise filter effectively suppresses abnormal input noise, while an internal blanking circuit minimizes the effects of output noise. It also provides appropriate time-delay characteristics required by IEC 60947-2, supporting stable leakage current detection and tripping operation.
NS-COB is available in 15 mA and 30 mA models and can be applied to residential earth leakage circuit breakers (ELCBs).
COBON TECH’s NS-COB is an integrated semiconductor circuit incorporating an amplifier circuit and a thyristor for high-speed earth leakage circuit breakers. It precisely amplifies and processes leakage current signals detected by a Zero-Phase Current Transformer (ZCT) and drives the built-in thyristor. It integrates a differential amplifier, time-delay circuit, latch circuit, and precision reference voltage circuit. In addition, a high-frequency noise filter effectively suppresses abnormal input noise, while an internal blanking circuit minimizes the effects of output noise. It also provides appropriate time-delay characteristics required by IEC 60947-2, supporting stable leakage current detection and tripping operation.
NS-COB is available in 15 mA and 30 mA models and can be applied to residential earth leakage circuit breakers (ELCBs).
Key Features
- Low Power Consumption
- Built-in High-Frequency Noise Filter
- Internal Blanking Circuit
- High-Gain Differential Amplifier Circuit
- Minimum 100 μA Output Current for SCR Drive
- Built-in Thyristor
- High Noise Immunity and Surge Margin
Applications
- Residential Earth Leakage Circuit Breakers (ELCBs)
NS-COB Specifications
| MODEL | Working Voltage | Trip Current (mA) | Trip Time | |||
|---|---|---|---|---|---|---|
| Spec | Min | Typ | Max | |||
| NS-COB 15 | 220 Vac | 15 | 9 | 11.5 | 13.5 | 30 ms |
| NS-COB 30 | 30 | 20 | 23 | 26 | ||
| CHARACTERISTICS | SYMBOL | VALUE (VDC) | ||||
| Min | Typ | Max | ||||
| Supply Voltage | T5 – T3 | 15 | 20 | 25 | ||
| Operating Junction Temperature | TJ | -35 ~ +80 °C | ||||
| Supply Current | T5 | 0.8 – 1.2 mA (Typ. 1.0 mA) |
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| Demensions | |||
|---|---|---|---|
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