Zhejiang HIITIO New Energy Co., Ltd. (“HIITIO”), a manufacturer of high-voltage DC electrical components, today announced the HBS1 Series Solid-State Circuit Breaker (SSCB), a protection device designed for DC systems where mechanical breakers face physical limits on switching speed and arc suppression.
Unlike a conventional breaker, which interrupts current by physically separating a pair of contacts, the HBS1 Series uses power semiconductor modules — IGBT or SiC MOSFET, depending on platform — to break current at the electronic level. DC has no natural current zero-crossing, so a mechanical contact opening on a DC fault can draw an arc that is difficult to extinguish; the semiconductor-based switching in the HBS1 Series avoids arc formation altogether. The fastest platforms in the series clear a fault within 10 to 20 microseconds of detection, compared to the millisecond-range response typical of thermal-magnetic breakers.
The HBS1 Series spans eight current platforms from 40A to 4000A, covering rated voltages from 220V to 1500V, with a rated electrical life of 1,000,000 operations across the range. The lineup includes two architectures: an all-solid-state configuration (SSCB) for applications that prioritize response speed and eliminate mechanical wear entirely, and a hybrid configuration (SSHCB) that carries steady-state current through a mechanical path at low conduction loss, switching to the semiconductor path only when a fault is detected. The hybrid option is positioned as a lower-cost alternative for industrial retrofit projects where an all-solid-state unit is not cost-justified.
Full-load efficiency reaches up to 99.8%, breaking capacity reaches up to 250kA depending on current platform, and voltage, current, power, and energy metering are built in. Communication options include RS-485 Modbus-RTU, Ethernet, and 4G, with connectivity to HIITIO’s cloud monitoring platform for remote status and fault telemetry.
How it compares to mechanical protection
| Fuse | Thermal-magnetic breaker | Hybrid breaker (SSHCB) | HBS1 (SSCB) | |
|---|---|---|---|---|
| Fault-clearing time | Melts once damage threshold is reached | Milliseconds | ~1.6ms | As fast as 10μs |
| Current-limiting | None | Limited | Limited, delayed by mechanical stage | Clamps to a few multiples of rated current |
| Arc on interruption | N/A | Yes | Yes, until semiconductor stage engages | None |
| Mechanical wear | None | Contact erosion over life | Reduced, mechanical path still present | None |
| Rated electrical life | Single use | ~10,000 operations | Up to 1,000,000 operations | Up to 1,000,000 operations |
Marine and industrial variants
Within the series, the HBS1-2500 is a liquid-cooled variant rated for 1000Vdc and 500A to 2500A, intended for shipboard DC distribution, energy storage, and propulsion protection applications. This variant is compliant with China Classification Society (CCS) guidelines for DC integrated power systems, hybrid power systems in ship applications, and battery-powered ships, and holds a Reliability Verification Compliance Certificate valid through April 2031. A separate compact, panel-mount variant, the HBS1-250, is rated for DC800V up to 250A and is intended for lower-current industrial and commercial distribution panels.
In one long-running industrial deployment — a process-industry site in metallurgical and chemical operations — HBS1 units have operated continuously for several years and completed more than one million switching cycles under real operating conditions, an early example of field-verified, rather than only laboratory-projected, million-cycle life for a breaker of this type.
Deployment history
HBS1 units are currently in service in several projects, including a DC distribution system at a China Southern Power Grid facility in Zhuhai, where a unit has been in continuous operation for more than three years; a photovoltaic-plus-storage installation in Inner Mongolia; a metro DC220V protection application; and an 800V DC data center distribution project. Additional deployments involve State Grid and a multinational new-energy manufacturing customer.
Positioning within HIITIO’s DC protection portfolio
The HBS1 Series sits alongside HIITIO’s existing lines of high-voltage DC contactors, semiconductor fuses, DC miniature circuit breakers, and surge protective devices, forming a coordinated protection stack for DC-heavy applications such as data centers, energy storage systems, rail transit, DC microgrids, and electric aircraft.
“DC systems are moving toward higher voltages and denser loads — a shift industry groups such as the Open Compute Project have also been documenting in data center power architecture — faster than mechanical protection technology was designed for. The HBS1 Series is our answer to that gap, and we built it to be verified in the field, not just rated on a datasheet,” said a HIITIO technical engineer.
About HIITIO
Zhejiang HIITIO New Energy Co., Ltd. was established in 2018, building on an R&D team from Hecheng Electric. The company designs and manufactures high-voltage DC electrical components for electric vehicle, solar energy, and energy storage applications, including HVDC contactors, semiconductor fuses, DC circuit breakers, surge protection devices, and power semiconductor modules. HIITIO’s products are used by customers across more than 50 countries and regions.
