"automatic voltage regulator AVR R448 voltage regulator of a sealed electronic devices, by adjusting the excitation current in order to stabilize the output voltage of the brushless generator." 
Generator output voltage is ajusted by using the voltage adjustment potentiometer on the AVR..cutting excitation current is accomplished by swiching off the supply power to AVR. 
"When applying a step load to the generator,the rotational speed(frequency) of the genset drops.if the speed is below the preset frequency,the LAMcircuits drops the voltage about 25%,as long as the speed hasnot recovered to normal values." 
"The LAM is used either to reduce the speed drop of the engine,during the step load, or to increase the applicable step load for the same speed variation so the engine can recover normal speed quickly." 

3.We mainly supply the following  AVR: 
General AVR Series Replacement:
GAVR-15A GAVR-12A GAVR-8A

Stamford Series AVR Replacement:
SX440 AS440 SX460 MX321 MX341

Leroy somer Series Replacement:
R448 R449 R230 R438

Marathon AVR Replacement:SE350   
"Fast delivery good service with high quantity and competitive price,offer high discounts on volume orders as well"