American SEL-421 Integrated Protection Device Automated Control System
LEHIY item code: LH-SEL-0023
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SEL-421 Integrated Protection, Automation, and Control System, sourced directly from SEL USA, ensuring genuine SEL-421 products. We offer remote or on-site installation and commissioning services for SEL products. The SEL-421 enables high-speed distance and directional protection, as well as control of two circuit breaker bays.
It protects any transmission line using a combination of phase distance, ground distance, and five zones of directional overcurrent A graphical user interface system provides logic and application templates for typical line protection schemes.
Coupled capacitor voltage transformer (CCVT) transient over-limit logic enhances the safety of Zone 1 distance elements.
Ground directional element logic optimizes directional element performance and eliminates many directional settings. Optional additional logic prevents Zone 1 from exceeding the range on series-compensated lines. Optional incremental components provide sub-loop operation for applications requiring high-speed fault clearing on critical elements. lines.
Transform substation modernization with optional Time Domain Link (TiDL) technology or using sampled value (SV) based technology according to IEC 61850-9-2. Subcycle Distance Protection—Protects critical transmission lines using high-speed quadrilateral, Moohm distance, and directional elements.
Optional subcycle distance elements and series compensation logic reduce operation time, thereby improving system stability. You can reverse the polarity of individual or grouped CTs or PTs to accommodate changes in field wiring or protection zones.
Single-Pole or Three-Pole Operation—Integrates programmable single-pole and three-pole tripping and reclosing of one or two circuit breakers into an integrated substation control system. Provides complete bay control through synchronization and voltage checks from multiple sources.
Series Compensated Transmission Lines—Detects faults other than series capacitors and prevents zone 1 out-of-bounds crossings on series compensated transmission using optional lines logic in the SEL-421-5 protection, automation, and control systems. Communication-Assisted Tripping Scheme—Configures transmission line protection without any external coordination equipment.
The SEL-421 includes settings for Allowable Out-of-Limit Tripping (POTT), Dual-Channel Allowable Out-of-Limit Tripping (POTT2), Phase-by-Phase Allowable Out-of-Limit Tripping (POTT3), Directional Comparison Unlock (DCUB), and Directional Comparison Lock (DCB).
Out-of-step blocking and tripping—Selects out-of-step blocking for distance elements or tripping during power fluctuations. protection, but can be used individually for monitoring and station integration applications.
Thermal Overload Protection—Uses three independent IEC 60255-149 thermal elements to activate control operations, issue alarms, or trip equipment when it overheats due to adverse operating conditions.
The SEL-2600 RTD module can provide ambient temperature measurement. Under-frequency load shedding—Operates the six-level frequency element as an under-frequency or over-frequency element. The frequency element is suitable for applications such as low-frequency load shedding and recovery control systems.
Flexible Communication Options—Uses Small Pluggable (SFP) transceivers on the process bus, station bus, and engineering access ports of a five-port Ethernet card. Choose between single-mode and multi-mode communication options for increased flexibility.
All ports support 100 Mbps SFP transceivers, and the process bus ports also support 1 Gbps SFP transceivers.
Our company is a leading supplier of the American SEL-421 integrated protection device automation control system. We source directly from the American SEL manufacturer, ensuring authenticity. For product details, please contact our sales department.
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| Brand Name: | SEL | Certification: | ISO9001, CE |
|---|---|---|---|
| Place of Origin: | China | Condition: | New |
| Warranty: | 1 year | Customized sourcing: | available |
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American SEL-421 Integrated Protection Device Automated Control System
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