The Indicator,electrical Tachometer, cataloged under National Stock Number 6620-00-030-1867, is classified within Federal Supply Class 6620 (Engine Instruments) of the Instruments and Laboratory Equipment group. Government technical data includes 19 specifications, cited from the U.S. Government catalog. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 6620-00-030-1867 |
| Item Name | Indicator,electrical Tachometer |
| FSC / FSG | 6620 / 66 — Engine Instruments |
| Status | ACTIVE |
| Individual Marking | G1; G2 |
| Mounting Facility Type and Quantity | 4 UNTHREADED HOLE(S) |
| FSC Application Data | 1. ENGINE INSTRUMENT,AIRCRAFT |
| Contact Type | PIN |
| Scale Marking | MAJOR GRADUATION AND MINOR GRADUATION |
| Current Type | AC |
| Electrical Connection Quantity | 2 |
| Mounting Stud Diameter | 0.170 INCHES NOMINAL IN |
| Electrical Connection Identifying Number | DESIGN STD NO. AND10066-14S-1F |
| Accuracy Rating | 100.0 REVOLUTIONS PER MINUTE SINGLE INDICATOR SINGLE SCALE |
| Scale Range | -0.1 TO 4500.0 REVOLUTIONS PER MINUTE SINGLE INDICATOR SINGLE SCALE |
| Scale Marking Transparency | LUMINOUS |
| Contact Quantity | 3 |
| Features Provided | INTEGRAL SYNCHROSCOPE |
| Presentation Type | SYNCHRO MOTOR |
| Nondefinitive Spec/std Data | AN5530-3A-12 REFERENCE NUMBER A |
| Height | 3.250 INCHES NOMINAL IN |
| Depth | 5.000 INCHES NOMINAL IN |
| Width | 3.250 INCHES NOMINAL IN |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Reference | Meaning |
|---|---|
| 751CU4-02WW | 3/9 Design control — primary reference Waltham Clock Co Inc |
| AN5530-3A12 | 4/1 Identification reference U.S. Government activity |
NSN 6620-00-030-1867 is a Indicator,electrical Tachometer, classified under FSC 6620, Engine Instruments. Status: active.
2 possible matches (shared part number, not a government interchangeability claim): 6620-00-244-8020, 6620-00-663-4211. Verify interchangeability with system specifications before substitution.
Key specifications for 6620-00-030-1867: Individual Marking: G1; G2; Mounting Facility Type and Quantity: 4 UNTHREADED HOLE(S); FSC Application Data: 1. ENGINE INSTRUMENT,AIRCRAFT; Contact Type: PIN. 19 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.