Popis
The main earth fault protection relays in distributions systems, power stations & large manufacturing / processing plants can fail to detect a high impedance break down to earth causing hazard to human life & potential damage to plant & equipment. In these & other situations demanding extra sensitive earth fault protection, the 2C138 relay using solid state techniques, can be applied to detect earth currents down to 0.5% of the CT nominal current.
The relay is tuned to reject 3rd & higher harmonic frequencies to avoid problems under quiescent conditions. An adjustable time delay is built in to provide stability during switching & other transient disturbances & to allow adequate grading with other protection systems at high fault current levels.
Features
- High sensitivity (0.1% of Is)
- 3rd harmonic & HF noise suppression
- Tuned to 50 Hz
- Optional reset functions: Instantaneous (Fast), definite time, count down
- 40-300V DC aux. supply
- 20-70V DC aux. optional
- Low CT burden & high thermal rating
- Optional 1A or 5A CT input
- Instantaneous pick up LED
- Configurable output contacts
- 0-31s time delay (125ms steps)
- Push button / electrical flag reset
- Non-volatile trip indication
- Multi voltage inhibit / enable input
- Multi voltage flag reset input
- Auxiliary supply fail alarm
- Flush or rack mount draw out case
- Made in Australia
