The I-VG1G is most likely a variant within Toshiba’s GR-100 series of protection relays, which were in production for over 20 years . This series was designed for comprehensive protection of electrical systems, including overvoltage and earth fault protection. Your specific model, AR61332FM1-2, is likely a unique ordering code specifying the hardware configuration, such as the number of binary inputs/outputs and the specific case type.
The “Ground Overvoltage Relay” description identifies its primary function: to protect equipment by detecting overvoltages that occur during earth faults, especially in systems with specific grounding methods like resistance or ungrounded neutral .
Functional Analysis
Although the exact manual is not available, the relay is likely to have functions very similar to other Toshiba GR-100 series relays, such as the GRD130 .
| Probable Feature | Description / Typical Function |
|---|---|
| Zero Phase Sequence Overvoltage Protection | The core function. It monitors “zero sequence voltage” (3V0), which appears only when an earth fault occurs. If this voltage exceeds a set threshold, the relay trips to isolate the fault . |
| Definite Time & Inverse Time Characteristics | The relay likely offers flexibility to trip either after a specific time delay (Definite Time) or with a delay that gets shorter as the overvoltage gets worse (Inverse Time) . |
| Hardware & Configurability | As a numerical relay, it likely featured a front panel with an LCD display, LEDs for status indication, and configurable binary inputs/outputs for integration with circuit breakers and alarm systems . |
| Technical Manual Context | For detailed settings and wiring, the GRD130 manual is a reliable reference. While not an exact match, the protection principles and hardware architecture would be very similar for your I-VG1G model . |
