SEL SEL-T400L Time-Domain Line Protection
SEL-T400L
Time-Domain Line Protection
Protecting Energy Moving at the Speed of Light®
Apply the SEL-T400L Time-Domain Line Protection for ultra-high-speed protection of transmission lines. With the breakthrough time-domain technology of traveling waves and incremental quantities, the SEL-T400L trips securely in as fast as 1 ms.
The relay records events with a 1 MHz sampling rate, locates faults to the nearest tower, and monitors the line for incipient faults, recurring faults, or incipient cable faults.
Adding the SEL-T400L to your line protection system can dramatically reduce your fault-clearing time and let you achieve the many benefits associated with speed.
Ultra-High-Speed Tripping With Security—The SEL-T400L features a traveling-wave differential scheme (TW87) over a dedicated point-to-point fiber channel;
an incremental-quantity distance element (TD21) and a POTT scheme with traveling-wave (TW32) and incremental-quantity (TD32) directional elements over a digital or an analog protection channel.
You can achieve 1–5 ms trip times, depending on the channel, line length, and system conditions.
Simplicity—Requiring only a few protection settings, the SEL-T400L is easy to learn, easy to apply, and easy to set.
The relay settings require only very basic short-circuit studies, and the relay settings are greatly resilient to power system evolution and changing short-circuit levels.
High-Fidelity Recording—The SEL-T400L provides high-resolution voltage and current recording with a 1 MHz sampling rate and an 18-bit resolution.
You can record and analyze high-frequency transients, such as traveling waves from faults, switching events, breaker reignition, and self-extinguishing faults.
The SEL-T400L also streams time-stamped Fast Time-Domain Values (FTDV).
Contact SEL to obtain a detailed format description as well as tools to experiment with this advanced SEL-T400L functionality.
Unparalleled Fault Locating—The SEL-T400L includes traveling-wave fault-locating methods that work with or without communications.
The SEL-T400L has a field-proven accuracy of about one tower span.
The double-ended fault location result is available within a few tens of milliseconds, allowing the SEL-T400L to control autoreclosing depending on the location of the fault (such as in applications on lines with cable sections).
The SEL-T400L also includes a line monitoring function, which can be used for condition-based line maintenance to prevent line faults and to discover weak spots along the line.
Testing Made Easy—Requiring only a few protection settings, the SEL-T400L is easy to commission.
You can apply any standard relay test set for testing the TD21 distance and TD32 directional elements or use the SEL-T4287 Traveling-Wave Test System for end-to-end testing of the TW87 scheme, the TW32 element, and the traveling-wave fault locator.
Event Playback—You can test the protection and fault-locating functions without a relay test set by using the built-in event playback function and events recorded in the field or simulated using electromagnetic transient programs.
With the event playback function, you can trigger a playback test in multiple relays based on time for end-to-end testing of the SEL-T400L protection schemes and multi-ended fault locators.