| Product standard | IEC 60947-2 covers low-voltage circuit-breakers, including many MCCBs used in industrial and commercial distribution. | Check the applicable standard and edition, product test documentation, and whether the exact model is covered by the stated certification. |
| Rated current (In) | MCCBs are available across a wide range of current ratings. The available ratings depend on the product family and manufacturer. | Confirm the frame size, rated current, adjustable settings, ambient-temperature conditions, and coordination with the protected cable and load. |
| Breaking capacity | Icu is the rated ultimate short-circuit breaking capacity; Ics is the rated service short-circuit breaking capacity. Both are stated at specified operating voltages. | Compare the published Icu and Ics values at the intended system voltage with the prospective short-circuit current at the installation point. |
| Trip-unit technology | MCCBs may use thermal-magnetic or electronic trip units. Available protection functions and adjustment ranges vary by model. | Check required overload and short-circuit protection settings, adjustment ranges, trip indication, and compatibility with the coordination study. |
| Number of poles | Common configurations include three-pole and four-pole breakers; other configurations depend on the product range and application. | Confirm the system arrangement, neutral switching requirements, pole protection, and local installation rules. |
| Voltage and frequency | A breaker’s ratings and performance are specified for particular operating voltages and, where applicable, frequencies. Ratings can differ between AC and DC applications. | Verify the exact AC or DC application rating, system voltage, frequency, and any series-pole requirements for DC use. |
| Accessories and integration | Depending on the model, accessories can include auxiliary contacts, alarm contacts, shunt trips, undervoltage releases, and motor operators. | Confirm accessory compatibility with the exact breaker, control voltage, wiring diagrams, and any required communication or remote-operation functions. |
| Environmental suitability | Operating limits, enclosure protection, and derating depend on the breaker and installation conditions; they should be taken from the product documentation. | Review temperature and altitude limits, enclosure requirements, pollution conditions, and any required derating for the installation site. |
| Certification and documentation | Certification and regulatory requirements vary by destination market and product application. | Request current certificates, test reports, technical data sheets, installation instructions, and the applicable declarations for the destination market. |
| Supply and after-sales support | Lead times, spare-part availability, technical support, and warranty terms are supplier- and market-specific rather than universal MCCB specifications. | Assess local service coverage, delivery commitments, replacement-part access, warranty conditions, and technical assistance in the required language and time zone. |