The Circuit Breaker, cataloged under National Stock Number 5925-00-299-7809, is classified within Federal Supply Class 5925 (Circuit Breakers) of the Electrical and Electronic Equipment Components group. The manufacturer of record is Telephone Company of America Incorporated. Government technical data includes 30 specifications, cited from the U.S. Government catalog. The record lists 1 manufacturer part number for this item, enabling identification through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5925-00-299-7809 |
| Primary Part Number | 50143-5 |
| Item Name | Circuit Breaker |
| FSC / FSG | 5925 / 59 — Circuit Breakers |
| Manufacturer | Telephone Company of America Incorporated |
| Status | ACTIVE |
| Reset Method | MANUAL |
| Internal Trip Release Configuration | SERIES TRIP SINGLE LOCATION |
| Operating Voltage Type and Rating Per Pole in Volts | 125.0 AC SINGLE LOCATION |
| Mounting Facility Type and Quantity | 2 THREADED HOLE(S) |
| Actuator Position Designation | AT POLE ONE |
| Frequency in Hertz | 60.0 SINGLE LOCATION |
| Fragility Factor | MODERATELY RUGGED |
| Body Style | SINGLE POLE TYPE |
| Ultimate Trip Rating of Continuous Current Rating Per Pole in Percent | 125.0 SINGLE LOCATION |
| Distance Between Centerlines of Mounting Facilities Parallel to Body Length | 2.740 INCHES MINIMUM AND 2.760 INCHES MAXIMUM IN |
| Arc Quenching Method | MAGNETIC BLOWOUT |
| Circuit Protection Type | OVERCURRENT SINGLE LOCATION |
| Body Width | 0.980 INCHES MINIMUM AND 1.000 INCHES MAXIMUM IN |
| Storage Type | GENERAL PURPOSE WAREHOUSE |
| Pole Quantity | 1 |
| Mounting Surface to Terminal End Distance | 2.611 INCHES NOMINAL IN |
| Maximum Continuous Load Current Rating Per Pole | 30.0 AMPERES AC SINGLE LOCATION |
| Trip Release Characteristic | TIME DELAY SINGLE LOCATION |
| Maximum Interrupting Capacity Current Type and Rating Per Pole in Amps | 2000.0 AC SINGLE LOCATION |
| Nominal Thread Size | 0.138 INCHES IN |
| Body Length | 3.709 INCHES MINIMUM AND 3.729 INCHES MAXIMUM IN |
| Trip Delay Time in Seconds Per Rated Continuous Current | 5.500 MINIMUM AT 200 PCT AND 19.000 MAXIMUM AT 200 PCT SINGLE LOCATION |
| Manual Actuator Type and Quantity | 1 TOGGLE |
| Inclosure Protection Type for Which Designed | DUSTPROOF AND FUNGUS PROOF |
| Thread Quantity Per Inch | 32 |
| Material | PLASTIC CASE |
| Actuator Function | TRIP-RESET |
| Terminal Type and Quantity | 2 THREADED STUD |
| Main Contact Tripping Mechanism Type | TRIP FREE |
| Thread Series Designator | UNIFIED NATIONAL COARSE (UNC) |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | Possible hazard — SDS may be required (DLA HMIC P) |
| Criticality Code | X |
| Part Number | Manufacturer |
|---|---|
| 50143-5 | Telephone Company of America Incorporated (USA) |
| Reference | Meaning |
|---|---|
| 50-309MG3-30 | 3/9 Design control — primary reference Eaton Corp Heinemann Products Commercial Controls Div |
| 50-309M6-30 | 5/9 Secondary reference Eaton Corp Heinemann Products Commercial Controls Div |
| SB1612-5 | 5/9 Secondary reference Itt Telecom Products Corp Network Systems Div |
NSN 5925-00-299-7809 is a Circuit Breaker, manufactured by Telephone Company of America Incorporated, classified under FSC 5925, Circuit Breakers. Status: active.
NSN 5925-00-299-7809 has 1 manufacturer part number on file: 50143-5 (Telephone Company of America Incorporated).
1 possible match (shared part number, not a government interchangeability claim): 3120-01-322-1424. Verify interchangeability with system specifications before substitution.
Key specifications for 50143-5: Reset Method: MANUAL; Internal Trip Release Configuration: SERIES TRIP SINGLE LOCATION; Operating Voltage Type and Rating Per Pole in Volts: 125.0 AC SINGLE LOCATION; Mounting Facility Type and Quantity: 2 THREADED HOLE(S). 30 specifications are documented in the U.S. Government catalog.
Possible hazard — SDS may be required (DLA HMIC P). Hazard information on this page is shown exactly as it appears in the DLA record.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-16.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-18.