120 Amp/12 Volt Model 621 Alternator
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BALMAR120 Amp/12 Volt Model 621 Alternator


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Model # 7807746 | Mfg # 621-120-DVUPC # 676205131087
120 Amp/12 Volt Model 621 Alternator




120 Amp/12 Volt Model 621 Alternator

Name Value
Dimensions 5 3/4" Diameter x 7 1/4" Height x 6 5/8" Length
Features Back-Up Internal Regulator
ISO Approved Ignition-Safe Design for Marine Gas or Diesel Engines
Meets USCG Title 33
ISO 8838 and SAE J1181 Safety Standards
Mount Type Single Foot 1" or 2"
Outputs 1 Output
Rated Output Power - 2000 RPM Hot 72 Amps
Rated Output Power - 6000 RPM Hot 112 Amps
Type Alternators
Pulley Groove Type Dual Groove
Voltage 12 Volts DC
Warranty Details One Year

Product Overview

6-Series Alternators

The Balmar 6-Series alternators combine the best of traditional Balmar quality with technology that is both more universal and more user-friendly than ever. The 6-series is the first high-output alternator that gives you the choice of either using its internal regulator or connecting to an external smart regulator. Patented Smart Ready internal regulation offers the 6-Series alternator the unique ability to be used as a stand-alone high-output OEM replacement for performance ski and wakeboard tow boats, day cruisers, or workboats, which have more electrical loads than ever! For sailors or power boaters demanding the very best in multi-stage external regulation, the Smart Ready system provides a dependable back-up for external voltage regulators. Isolated Ground terminals are now standard, improving the system ground and noise reduction. 6-Series alternators utilize dual internal fans and an open frame case design for improved alternator cooling. A universal crown assures an easy fit on most modern engines. Model 621 alternators replace 1' single foot or 2" single foot alternators.

  • Dual internal fans provide added cooling
  • Patented Smart Ready Internal Regulation
  • Corrosion resistant powder-coated cast aluminum case
  • Five-way universal tensioning crown
  • 120 Amps, 12 Volts
  • 1" or 2" "ID Saddle Mount (Model 621)
  • Ignition-safe for marine gas or diesel engines

6-Series Alternator Data Sheet

Balmar Alternator Application Guide


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