The Motor-Tachometer Generator, cataloged under National Stock Number 6105-00-329-4012, is classified within Federal Supply Class 6105 (Motors, Electrical) of the Electric Wire, Power, and Distribution Equipment group. The manufacturer of record is Firstmark Aerospace Corp. Government technical data includes 26 specifications, cited from the U.S. Government catalog. The record lists 2 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 4 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active. Unit of issue: EA.
| Parameter | Value |
|---|---|
| NSN | 6105-00-329-4012 |
| Primary Part Number | 20D501-4 |
| Item Name | Motor-Tachometer Generator |
| FSC / FSG | 6105 / 61 — Motors, Electrical |
| Manufacturer | Firstmark Aerospace Corp |
| Status | ACTIVE |
| Mounting Facility Type and Quantity | 1 CLAMP COLLAR |
| Spline Minor Diameter | 0.0830 INCHES NOMINAL SINGLE END IN |
| Phase | SINGLE INPUT |
| Shaft Diameter | 0.1250 INCHES NOMINAL SINGLE END IN |
| Frequency in Hertz | 400.0 INPUT |
| Current Type | AC INPUT |
| Calibration Speed in RPM | 1000.0 |
| Mounting Method | CLAMP RING(S) |
| Spline Length | 0.2180 INCHES NOMINAL SINGLE END IN |
| Cooling Method | SELF-VENTILATED |
| Features Provided | VERTICAL MOUNTING POSITION AND HORIZONTAL MOUNTING POSITION |
| Maximum Operating Altitude Rating | 60000.0 FEET FT |
| Spline Quantity | 13 SINGLE END |
| Connection Type and Voltage Rating in Volts | 6.0 LINE TO NEUTRAL SINGLE INPUT |
| Calibration Voltage Output Type in Volts | 6.0 AC |
| Torque Rating and Type | 0.3 INCH-OUNCES STALLED IN |
| Length of Shaft From Housing | 0.218 INCHES SINGLE END IN |
| Control Field Voltage Type and Rating in Volts | 26.0 AC |
| Enclosure Feature | TOTALLY ENCLOSED |
| Power Rating | 1.700 WATTS OUTPUT |
| Shaft End Characteristic | A14 SINGLE STYLE SINGLE END |
| Excitor Type | SEPARATELY EXCITED |
| Terminal Type and Quantity | 9 WIRE LEAD |
| Rotor Speed Rating in RPM | 9500.0 SINGLE NO LOAD |
| Temp Rating | -55.0 OPERATING CELSIUS AND 85.0 OPERATING CELSIUS |
| Inclosure Specification | COMMERCIAL |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Unit of Issue | EA |
| Part Number | Manufacturer |
|---|---|
| 20D501-4 PRIMARY | Firstmark Aerospace Corp (USA) |
| 1775310-3 | Honeywell International Inc. Dba Honeywell International (USA) |
| Reference | Meaning |
|---|---|
| 20D501-4 | 5/9 Secondary reference U.S. Government activity |
| A203420-13-2-3 | 5/9 Secondary reference U.S. Government activity |
| 1775310-3 | 5/9 Secondary reference Lockheed Martin Corporation Div Rms - Mitchel Field |
| A2794410160 | 5/9 Secondary reference U.S. Government activity |
NSN 6105-00-329-4012 is a Motor-Tachometer Generator, manufactured by Firstmark Aerospace Corp, classified under FSC 6105, Motors, Electrical. Status: active.
NSN 6105-00-329-4012 has 2 manufacturer part numbers on file: 20D501-4 (Firstmark Aerospace Corp), 1775310-3 (Honeywell International Inc. Dba Honeywell International).
Key specifications for 20D501-4: Mounting Facility Type and Quantity: 1 CLAMP COLLAR; Spline Minor Diameter: 0.0830 INCHES NOMINAL SINGLE END IN; Phase: SINGLE INPUT; Shaft Diameter: 0.1250 INCHES NOMINAL SINGLE END IN. 26 specifications are documented in the U.S. Government catalog.
No hazard code in the DLA record (HMIC N). 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.