SPRING AS-GAS 1641328 - Caterpillar

Introduction
For Specifications with illustrations, make reference to Specifications for 3406C Generator Set Engine Attachments, SENR1096. If the Specifications in SENR1096 are not the same as in the Systems Operation, Testing & Adjusting, look at the printing date on the cover of each book. Use the Specifications given in the book with the latest date.Fuel System
2301A Electric Governor
Refer to 2301A Electric Governor Service Manual, SENR4676 for additional information.The 2301A Electric Governor Control System consists of the components that follow: 2301A Electric Governor Control (EGC), actuator, Magnetic Pickup.
2301A Electric Governor Control (EGC)The 2301A Electric Governor System gives precision engine speed control. The 2301A control measures engine speed constantly and makes necessary corrections to the engine fuel setting through an actuator connected to the fuel system.
(Typical Illustration) Magnetic Pickup Location
(1) Magnetic pickup. (2) Flywheel housing.The engine speed is felt by a magnetic pickup. This pickup makes an AC voltage that is sent to the 2301A Control. The 2301A Control now sends a DC voltage signal to the actuator.
EG3P Actuator
(3) Actuator. (4) Actuator lever.The actuator changes the electrical input from the 2301A Control to a mechanical output that is connected to the fuel system by linkage. For example, if the engine speed is more than the speed setting, the 2301A Control will decrease its output and the actuator will now move the linkage to decrease the fuel to the engine.Magnetic Pickup
Schematic Of Magnetic Pickup
(1) Magnetic lines of force. (2) Wire coils. (3) Gap. (4) Pole piece. (5) Flywheel ring gear.The magnetic pickup is a single pole, permanent magnet generator made of wire coils (2) around a permanent magnet pole piece (4). As the teeth of the flywheel ring gear (5) cut through the magnetic lines of force (1) around the pickup, an AC voltage is generated. The frequency of this voltage is directly proportional to engine speed.This engine speed frequency signal (AC) is sent to the 2301A Control Box where a conversion is made to DC voltage. The DC signal is now sent on to control the actuator, and this voltage is inversely proportional to engine speed. This means that if engine speed increases, the voltage output to the actuator decreases. When engine speed decreases, the voltage output to the actuator increases.Woodward PSG Governor
Typical Example Schematic Of PSG Governor
(1) Return spring. (2) Output shaft. (3) Output shaft lever. (4) Strut assembly. (5) Speeder spring. (6) Power piston. (7) Flyweights. (8) Needle valve. (9) Thrust bearing. (10) Pilot valve compensating land. (11) Buffer piston. (12) Pilot valve. (13) Pilot valve bushing. (14) Control ports. (A) Chamber. (B) Chamber.Introduction
The Woodward PSG (Pressure compensated Simple Governor) can operate as an isochronous or a speed droop type governor. It uses engine lubrication oil, increased to a pressure of 1200 kPa (175 psi) by a gear type pump inside the governor, to give hydra/mechanical speed control.Pilot Valve Operation
The governor is driven by the governor drive unit. This unit turns pilot valve bushing (13) clockwise as seen from the drive unit end of the governor. The pilot valve