Replace Leroy Somer AVR R448 Automatic Voltage Regulator

Replace Leroy Somer Generator Voltage Regulator AVR R448

Replacement Models: R220, R230, R250, R438, R448, R449, R450

Original Modules: D510C, R120, R129, R250, R438, R449, R450, R450M, R450T, R630, R726, R731 

The Brands / Part No. here are for reference purpose only, our products are replacement / not original.

Compatible Part Numbers:

SDMO AVR 330410089 Voltage Regulator

FG Wilson AVR 922-124 Voltage Regulator

Olympian AVR 922-124 Voltage Regulator

The circuitry of the Leroy Somer R448 Voltage Regulator AVR provides closed loop control of the alternator output voltage by regulating the exciter field current.

The R448 Leroy Somer AVR can be powered by Shunt, AREP or PMG field excitation systems and is fitted as standard on: 

5000 Series Alternators

6000 Series Alternators

7000 Series Alternators

Load Adjustment Module (LAM): 

On load impact, the rotation speed of the generator set decreases. When it passes below the preset frequency threshold, the LAM causes the voltage to drop by approximately 15% and consequently the amount of active load applied is reduced by approximately 25% until the speed reaches it's rated value again

Specification of Leroy Somer R448 AVR: 

Voltage regulation ± 0.5%

Short circuit capability: 3 x Irated for 10 seconds (AREP or PMG excitation)

Voltage sensing:

Ø  95 to 140 volts (50/60 Hz) or

Ø  170 to 260 volts (50/60 Hz) or

Ø  340 to 520 volts (50/60 Hz)

Response time:

Normal (1 sec) for ± 20% voltage variation or Rapid (0.3 sec) for ± 20% voltage variation

Remote voltage adjustment range of: ± 5%

Adjustment capability: 

The R448 AVR features the following adjustment capabilities (Please note that no adjustments should be made prior to careful consultation of the alternator installation and maintenance manual): 

Ø  Quadrature droop adjustment

Ø  AVR Voltage adjustment

Ø  Stability adjustment

Ø  LAM Threshold (underspeed) adjustment

Ø  Excitation ceiling adjustment

Ø  Selection of single phase or three phase*

Ø  voltage sensing

Ø  Selection of normal or rapid response time

Ø  50 Hz or 60 Hz frequency option

Ø  Remote voltage adjustment option

Ø  LAM enable/disable option

Ø  Alternator frame selection

Excitation system selection