PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

21991Switch,rotary

Helle Engineering Inc · NSN 5930-01-171-5543 · FSC 5930 · No Item Name Available
Verified by PartsTable
NSN 5930-01-171-5543 — this item is cataloged by the U.S. Government under National Stock Number 5930-01-171-5543. Primary manufacturer part number: 21991.
Features
  • Switch,rotary — FSC 5930
  • Precious Material and Location: CONTACT AND ROTOR BLADE SURFACES SILVER
  • Style Designator: CIRCULAR WAFER, BUSHING MOUNT
  • Switch Actuator Positioning Increment: 30.0 DEGREES SINGLE ACTUATOR
  • Nonturn Device Radius: 0.531 INCHES NOMINAL AT 6:00 OCLOCK IN
  • Switch Contact Basic Design: NONPILE-UP SYMMETRICAL
  • Contact Voltage Rating in Volts: 28.0 HIGHEST DC VOLTAGE RATING AT SEA LEVEL
  • Pole Quantity: 4 SINGLE SECTION REAR
Applications
  • Circuit control and protection
  • Equipment power management
  • Signal routing
General Description

The Switch,rotary, cataloged under National Stock Number 5930-01-171-5543, is classified within Federal Supply Class 5930 (No Item Name Available) of the Electrical and Electronic Equipment Components group. The primary manufacturer of record is Helle Engineering Inc. Government technical data includes 27 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 1 commercial cross-reference from 1 manufacturer, enabling identification through both NSN and commercial part number lookups. 4 verified substitutes exist in the FLIS interchangeability database. Current acquisition status: Active.

Technical Specifications
ParameterValue
NSN5930-01-171-5543
Primary Part Number21991
Item NameSwitch,rotary
FSC / FSG5930 / 59 — No Item Name Available
ManufacturerHelle Engineering Inc
StatusACTIVE
Precious Material and LocationCONTACT AND ROTOR BLADE SURFACES SILVER
Style DesignatorCIRCULAR WAFER, BUSHING MOUNT
Switch Actuator Positioning Increment30.0 DEGREES SINGLE ACTUATOR
Nonturn Device Radius0.531 INCHES NOMINAL AT 6:00 OCLOCK IN
Switch Contact Basic DesignNONPILE-UP SYMMETRICAL
Contact Voltage Rating in Volts28.0 HIGHEST DC VOLTAGE RATING AT SEA LEVEL
Pole Quantity4 SINGLE SECTION REAR
Mounting MethodTHREADED BUSHING SINGLE MOUNTING FACILITY
Shaft TypeROUND, FLATTED SINGLE ACTUATOR
Nominal Thread Size0.375 INCHES SINGLE MOUNTING FACILITY IN
Throw Quantity2 SINGLE SECTION REAR
Terminal TypeTAB, SOLDER LUG
Contact Load Current Rating350.0 MILLIAMPERES RESISTIVE LOAD AC AT SEA LEVEL
Shaft Diameter0.250 INCHES NOMINAL SINGLE ACTUATOR IN
Shaft Length0.500 INCHES NOMINAL SINGLE ACTUATOR IN
Contact Voltage Rating in Volts6.0 LOWEST DC VOLTAGE RATING AT SEA LEVEL
Switch Actuator Momentary PositionCLOCKWISE SINGLE ACTUATOR
Switch Actuator Indexing Position Quantity2 SINGLE ACTUATOR
Thread Length0.375 INCHES NOMINAL SINGLE MOUNTING FACILITY IN
Nonturn Device TypeTAB AT 6:00 OCLOCK
Thread Class2A SINGLE MOUNTING FACILITY A
Individual Section Quantity1
First Flat Length0.281 INCHES MINIMUM AND 0.312 INCHES MAXIMUM SINGLE ACTUATOR IN
Flat Height0.200 INCHES NOMINAL SINGLE ACTUATOR IN
Contact Voltage Rating in Volts115.0 AC AT SEA LEVEL
Thread Series DesignatorUNEF SINGLE MOUNTING FACILITY
Contact Load Current Rating5.5 AMPERES RESISTIVE LOAD LOWEST DC VOLTAGE RATING AT SEA LEVEL
Lifecycle & Compliance
Acquisition StatusACTIVE
HAZMATNo
Verified Substitutes 4
5365-00-033-25302-199-1 INTERCHANGEABLE
Shim
Amphenol Corp Div Amphenol Aerospace Operations
4320-00-334-414612226 INTERCHANGEABLE
Pump Unit,rotary
Industrial Technologies and Services Llc
5998-01-087-779921991 INTERCHANGEABLE
Circuit Card Assembly
Spectral Dynamics Inc
6515-01-446-9743219.91 INTERCHANGEABLE
Washer,bone Screw
Depuy Synthes Sales Inc Dba Depuy Synthes Trauma Div Depuy Synthes Sales, Inc., D/b/a Depuy Synthes Trauma
Cross-Reference Index
Part NumberManufacturer
21991 Helle Engineering Inc (USA)
Related Parts
5365-00-033-2530INTERCHANGEABLE
SHIM
2-199-1
4320-00-334-4146INTERCHANGEABLE
PUMP UNIT,ROTARY
12226
5998-01-087-7799INTERCHANGEABLE
CIRCUIT CARD ASSEMBLY
21991
6515-01-446-9743INTERCHANGEABLE
WASHER,BONE SCREW
219.91

Frequently Asked Questions

What is NSN 5930-01-171-5543?

NSN 5930-01-171-5543 is a Switch,rotary, manufactured by Helle Engineering Inc, classified under FSC 5930 (No Item Name Available). Status: active.

What are the part numbers for NSN 5930-01-171-5543?

NSN 5930-01-171-5543 has 1 cross-referenced part number: 21991 (Helle Engineering Inc).

What NSN replaces 5930-01-171-5543?

There are 4 known substitutes for 5930-01-171-5543: 5365-00-033-2530, 4320-00-334-4146, 5998-01-087-7799 and 1 more. Verify interchangeability with system specifications before substitution.

What are the specifications of 21991?

Key specifications for 21991: Precious Material and Location: CONTACT AND ROTOR BLADE SURFACES SILVER; Style Designator: CIRCULAR WAFER, BUSHING MOUNT; Switch Actuator Positioning Increment: 30.0 DEGREES SINGLE ACTUATOR; Nonturn Device Radius: 0.531 INCHES NOMINAL AT 6:00 OCLOCK IN. 30 total characteristics are documented in the Federal Logistics Information System.

Validated with multiple authoritative sources, including Government, OEM, and Certified sources.
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