Schweitzer Engineering Laboratories (SEL) added Time-Domain Link (TiDL) technology, an substation solution that digitizes analog signals, to its SEL-400 series relay product line.
The TiDL solution replaces copper cables with fiber-optic cables. It is cybersecure and simple to apply, with no network engineering and no external time reference required, according to the company. Because of the nonroutable protocol, the direct fiber connection between field modules and the relay in the control house, there is no need for switches or routers.
In a TiDL implementation, SEL-2240 Axion devices are located close to the primary equipment in the substation yard and act as field modules. TiDL’s simple point-to-point architecture transports the data over fiber-optic cable to a TiDL-enabled SEL-400 series relay in the control house.
The Axion’s 24 kHz sampling rate improves the accuracy of metering and frequency tracking, and its modular architecture allows the user to select analog input, digital input and digital output modules to match the application. Relay settings remain the same as those in current SEL-400 series models.
“With TiDL, you can achieve your digital substation needs in the simplest way possible,” says Joe Casebolt, SEL’s director of quality. “One of the ways we reduce complexity is by using point-to-point connections. No switches, zero network configurations, no settings for the field modules and the same protection algorithms and schemes that a user of a 400 series is already familiar with. You literally plug in the [fiber] cables, and it begins working.”
TiDL improves safety by removing high-energy cables from the control house where personnel typically work. Replacing copper cabling with fiber-optic cables reduces the costs and time associated with copper wiring installation, commissioning, and documentation.
