STAMFORD® SX-421 Voltage Regulator AVR

STAMFORD® SX-421 Voltage Regulator AVR

Product Group STAMFORD® voltage regulators

Part/Model #: SX 421

Quality: Factory tested, satisfaction guaranteed

Condition: 100% genuine, certified factory original

Warranty: Full factory warranty

Pricing: Below MSRP

Shipping: Overnight as available

Product Information

STAMFORD® SX-421 Voltage Regulator

The STAMFORD® SX421 AVR is a state-of-the-art regulator from STAMFORD® that utilizes a 3-phase system featuring:

  1. Sensing Resistors
  2. Quadrature Droop Circuit
  3. Stability Circuit
  4. Power Control Driver

In addition to these features, the SX421 includes the following controls:

  1. Voltage Adjustment
  2. Stability Selection
  3. Stability Adjustment
  4. Frequency Selection
  5. Under Frequency Roll Off (UFRO) Adjustment
  6. Dip Adjustment
  7. Droop Adjustment
  8. Over Voltage (Over V) Adjustment

Sensing input voltage is 170-250V ac 3-phase, 3-wire and Frequency 50-60 Hz nominal. Output voltage is 90V dc @ 207V ac max.

Identical Automatic Voltage Regulator as:
Olympian VR 594-080
FG Wilson VR 594-080
STAMFORD® VR E000-24210/1P

Brand New! In Stock. Ships same day. Worldwide.

Cummins Generator Technologies

Manufacturing Origin:
United Kingdom (UK)


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Knowing which part you need isn’t always as easy as you might expect. That’s why Ward Leonard provides Authorized Tech Support to help you define exactly what you need to get your alternator back up and running. Much more than a distributor, we’re an Authorized Service & Repair Center that has handled hundreds of alternator projects over the years — and there isn’t a part we don’t know, can’t find, or can’t repair. Call 1-800-673-0531 to discuss your specific part — or any other maintenance and repair — needs.

STAMFORD® Alternator Service Guide

Maximize the life of your STAMFORD® alternator by following the recommended scheduled service and repair activities in this easy-to-understand guide. Activities include: Commission, Post Commission 250 hours/6 months, 1,000 hours/1 year service, 10,000 hours/2 year service and 30,000/5 year Service Kits for the following models:

  • P0/P1 Alternators
  • UC22/UC27 Alternators
  • HC4/HC5/HC6 Alternators
  • P7 Alternators
  • P80 Alternators
  • S Range

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