Loading... Please wait...
  • Zeftronics Alternator Controller
R25101 Rev A

Zeftronics Alternator Controller (R25101 Rev A)

R25101 Rev A
2.00 LBS
Usually ships withn 24 hours
Calculated at checkout

Product Description

28V Alternator Controller

h3>What’s included:

  • Installation Drawing
  • Warranty Card
  • Product Eligibility Catalog (PEC)
  • Troubleshooting Notes
  • Instructions For Continued Airworthiness Maintenance (ICA)

Product Features:

Voltage Regulation, IC Sense reference

The Voltage Regulator keeps the bus voltage constant by increasing the current to the alternator’s field with a system load increase, decreasing it with a load decrease.

Field-to-Ground Fault Protection (GFP)

If the alternator’s field become shorted to ground, the GFP will deactivate the Voltage Regulator, and switch on the unit’s Red TSL, and the LVI light on the instrument panel.

Battery Off-Line Voltage Regulation (BOLR)

The design of the ACU allows it to excite the field of a rotating alternator (with a minimum residual voltage) and regulate the bus voltage with the battery off-line. This allows the system to carry electrical load if the battery or the battery relay fails.

Trouble-Shooting Light (TSL)

Green, Red, Off Alerts the user to the condition of the Alternator / ACU system. TSL: RED light with the Bat & Alt switches on means there is an internal or external ground short in the alternator field circuit. TSL: GREEN light with the engine running, means there is power coming out of the ACU. With the light Green, a bus voltage of 27.3 to 28.1V (for R25101 Rev A and R25102 Rev A , 28.4 to 28.8V) indicates a system that is operating correctly, and a sustained bus voltage of 20V to 25.6V means an open alternator field or field wire. Unless the ACU is damaged, the light should be Green when the master switch is on. TSL: Off with the Master switch on and no power to the ACU (red wire, pin 1), means that one power input device (like switch, circuit breaker, or wiring). If there is voltage on the red wire (pin 1) then the ACU is damaged.

Other Features:

  • Increased Regulator life
  • Reduced panel lights flicker
  • Protects against grounded alternator field
  • ACU controls & keeps the Alternator on-line if the Bat fails
  • Identifies grounded field
  • Reduce trouble-shooting time

Click here for cross reference guide

Additional Information

Weight .3 lbs
Model Number

R25101 Rev A

Voltage Reg. (VR)

27.7V +/- 0.4V

Max Field Current




Approval Type

FAA-PMA Approved

Document Approval

Log Book Entry Required

OEM PN: (Cessna)

CESSNA: C611004-0101 + C593001-0101, C611002-0205 + C593001-0101

OEM PN (Electrodelta)

ELECTRODELTA: VR500-0101 + OS100

Aircraft Common Name

Skywagon, Super Skylane, Stationair, Super Cargo Master, Turbo Stationair, Centurion, Cardinal, Cardinal RG, Classic, Skyhawk, Hawk XP, Cutlass, Cutlass RG, Powermatic, Skyhawk Powermatic, Skymaster,

Approved Aircraft

CESSNA: 152, A152, F152, FA152. 172, 172H,172N; F172; FR172K; R172, R172K; 177, 177A, 177B, 177RG; 180, 180K; 182, 182P, 182Q, F182, 182P, 182Q; R182, FR182; T182,TR182. 185,A185F. 188, A188, A188A, A

Find Similar Products by Tag

Product Reviews

This product hasn't received any reviews yet. Be the first to review this product!

Customers also viewed

Click the button below to add the Zeftronics Alternator Controller (R25101 Rev A) to your wish list.