Product Overview
The ABB 424K1105 is a precision synchronism check relay from the ABB Circuit Shield series, specifically the 25S type, designed to ensure safe and reliable paralleling of electrical power systems . This relay serves as a critical safety interlock in generator grid-connection, busbar coupling, and automatic transfer applications, preventing damaging out-of-phase breaker closures that can result in severe mechanical stress to generators, transformers, and other power system equipment. The ABB 424K1105 continuously monitors voltage magnitude, frequency, and phase angle on both sides of a circuit breaker, only permitting a close command when all parameters fall within a pre-defined acceptable window .
The ABB 424K1105 operates with a 110 V AC coil and provides 2 Form C contact sets (2NO + 2NC) rated at 10 A, making it suitable for direct integration into circuit breaker control circuits or for driving intermediate relays . For applications requiring dead-bus or dead-line closing capability, the Type 25V variant of the ABB 424K1105 includes an internal selector switch that allows the user to configure the relay for synchronism check only, high bus-dead line, or high line-dead bus logic . The ABB 424K1105 features precise solid-state measuring circuitry with calibrated, adjustable controls, housed in a compact DIN rail mount enclosure that is well-suited for switchgear and control panels .
Technical Specifications
| Parameter Name | Value |
|---|---|
| Product Model | ABB 424K1105 |
| Manufacturer | ABB |
| Product Series | Circuit Shield 25S |
| Product Type | Synchronism Check Relay |
| Coil/Control Voltage | 110 V AC (50/60 Hz) |
| PT Input Voltage | 100/110/120 V AC |
| Frequency Range | 45 – 65 Hz |
| Contact Configuration | 2 Form C (2NO + 2NC) |
| Contact Rating | 10 A @ 250 V AC / 30 V DC (resistive) |
| Dead Bus/Dead Line Setting | 0 – 120 V adjustable (factory default 30 V for 25V type) |
| Time Delay | 0 – 10 seconds adjustable |
| Pickup Time Delay | 0.1 – 1.5 seconds adjustable |
| Power Consumption | ≤ 4 VA |
| Mounting Type | 35 mm DIN Rail |
| Operating Temperature | -20 °C to +60 °C |
| Storage Temperature | -40 °C to +85 °C |
| Protection Class | IP20 |
| Insulation Class | Class F |
| Dimensions | Approx. 167 x 35 x 254 mm |
| Weight | Approx. 0.35 kg |
| Certifications | CE, UL, CSA, IEC 60255 |
| Lifecycle Status | Discontinued (limited stock available) |
Main Features and Advantages
Precise Synchronism Verification
The ABB 424K1105 utilizes precise solid-state measuring circuitry to continuously analyze voltage magnitude, frequency deviation, and phase angle between two independent voltage sources. Unlike standard voltage or phase-sequence relays, the ABB 424K1105 performs a comprehensive check of all three synchronizing criteria before issuing a close command . This ensures that breaker closures occur only when the vector difference between the two systems is within acceptable limits, preventing the violent mechanical and electrical transients associated with out-of-phase paralleling.
Flexible Dead Bus/Dead Line Logic
The Type 25V version of the ABB 424K1105 includes a front panel selector switch that provides configurable logic options . This allows the relay to be set for synchronism check only, high bus-dead line, high line-dead bus, or simultaneous high bus-dead line / high line-dead bus operation. This flexibility makes the ABB 424K1105 highly adaptable to various substation configurations and operational scenarios, eliminating the need for additional undervoltage relays.
Adjustable Control Parameters
The ABB 424K1105 offers calibrated, user-adjustable controls for key operating parameters. The acceptable phase angle window, time delay, and dead-bus/line voltage thresholds can be fine-tuned to match specific site requirements . This adjustability allows engineers to optimize the relay for different system conditions, providing the right balance between security and availability in critical power applications.
Robust Construction for Industrial Environments
Designed for demanding power system environments, the ABB 424K1105 features transient immunity exceeding 2500 V and seismic capability greater than 6g ZPA, meeting ANSI/IEEE C37.90.1 standards . The relay offers 2000 V AC dielectric strength to all circuits, ensuring reliable operation even under fault conditions. Its compact DIN rail mount design enables efficient installation in space-constrained switchgear and control cabinets.
