Check the listing for details. ESD5550M Speed Control Units ROHS (Authentic). Condition: Seller refurbished. Listed at 288.50 USD. Multi-V DC • Overspeed Switch • Expanded Gain and Stability Range (Replace Ghana Controls)Isochronous, variable and droop operationAdjustable PIDSingle-element speed switchIdle speed adjustmentAuxiliary accessory inputsSpeed rampingSoft couplingStarting fuel controlSingle-element speed optionTwo-element speed optionAnti-windup circuit optionEFC forward acting/light-force optionThe ESD5550/5570 Series speed control unit is an all- electronic device designed to control engine speed with fast and precise response to transient load changes. This closed loop control, when connected to a proportional electric actuator and supplied with a magnetic speed sensor signal, will control a wide variety of engines in an isochronous or droop mode. It is designed for high reliability and built ruggedly to withstand the engine environment. The primary features of the ESD5550/5570 Series speed control unit are the engine STARTING Fuel and SPEED RAMPING adjustments. The use of these features will minimize engine exhaust smoke experienced prior to attaining engine operating speed.