S804B-C125 breaker review: 125 A rating, four-pole isolation and coordination
S804B-C125 is an ABB S800-series high-performance miniature circuit breaker identified as a four-pole, 125 A, C-characteristic device. The code should be checked against the installed label and the applicable ABB product sheet before matching fault-duty values. S804B-C125 protects the circuit within its specified voltage and breaking-capacity limits; it is not a generic substitute for every 125 A MCCB.
Key technical data
| Technical item | Verified value / selection note |
|---|---|
| Type | S804B-C125 |
| Pole count | 4-pole S804 family designation |
| Rated current | 125 A |
| Trip curve | C characteristic designation; confirm trip limits and applicable standard |
| Product role | High-performance miniature circuit breaker |
| Breaking capacity | Verify exact Icn/Icu value on the rating label and matching ABB data |
Identification note: S804B-C125. The figures above are selection references; verify the actual label, duty rating, approvals, firmware and options for the exact unit before purchase or engineering release.
System role and signal path
Signal path: S804B-C125 is one element in a wider control or measurement loop. Check what the field device measures or switches, how the controller receives that state, and what diagnostic behavior the operator should see.
Interface and control path
Selection of S804B-C125 requires checking the exact short-circuit rating, coordination tables, conductor ampacity, ambient-temperature derating and any upstream backup protection. Compare the enclosure and busbar interface with the panel design. Never infer interrupting capacity or selectivity from the C125 marking alone.
Related configurations
The following model references belong to the same identifiable family as S804B-C125; they are configuration alternatives, not automatic substitutes. Compare each complete designation and application before selecting.
- 2CCS814001R0844 ,S804B-C125
For the S804B-C125 record, retain the full type string and do not infer range, rating or compatibility from a shortened family code.
Field validation
Install S804B-C125 in the compatible assembly and torque connections to the specified value. Confirm conductor preparation, pole identification and clearances, then perform continuity and insulation checks before energizing. Validate trip operation using the approved commissioning method and record the protective-device setting and coordination basis.
Before replacement, compare S804B-C125 with the installed revision, accessories, wiring and engineering configuration.
