SEFI-3 short-circuit earth fault indicator is a kind of real-time monitoring device which is installed in the distribution network system, ring network switch, cable branch box and box transformer. It is used to indicate the short circuit and single-phase earth fault of the corresponding cable section.
The SEFI-3 short circuit and ground fault indicator is a real‑time monitoring device installed on ring‑main switches, cable distribution boxes, or transformer stations to detect short‑circuit and single‑phase ground faults. When a fault occurs, the device signals the fault segment and can transmit the alarm to a monitoring center for rapid response.
The guide describes the main functions (short‑circuit alarm, ground alarm, low‑voltage alarm, automatic and manual reset, remote reset and signal transmission), step‑by‑step installation of the host and sensors, operation procedures such as testing and alarm clearing, technical specifications, equipment list, and ordering information. This manual is written in Chinese.
| Short‑circuit current alarm range | 200 A–2000 A |
|---|---|
| Ground current alarm range | 10 A–150 A |
| Power source | ER14505 Li‑ion battery 3.6 V (≥8 years life) |
| Auto‑reset time options | 4, 8 (default), 12, 16 hours |
| Ingress protection rating | IP40 for host, IP65 for sensors |
| Remote transmission relay output | 24 VDC 1 A |
| Maximum short‑circuit sensor current | 20 kA |
| Operating temperature range | -40 °C to +75 °C |
| Applicable system voltage | Up to 20 kV |
The short‑circuit sensor detects current that exceeds the preset value and sends an alarm signal via fiber‑optic cable to the host, which then displays the short‑circuit alarm.
Press and hold the “复位/测试” (Reset/Test) button on the host panel for about 2 seconds to clear the alarm.
Open the host panel, replace the ER14505 Li‑ion battery, then press the Reset/Test button to clear any voltage‑alarm indication.