STEM ASSEMBLY 90 degrees 5P4699 - Caterpillar

Overspeed Test
Test the engine speed switch at 75 percent of the overspeed setting.
While the engine is running, increase the engine speed above 75 percent of the overspeed setting. Alternately connect a 163-0096 Diagnostic and Calibration Tool to the engine speed switch in order to simulate engine speed. See Table 1 for speeds and frequencies.
Connect the jumper wire for 75 percent verify in the engine speed switch. The engine will shut down. Output 0 of the engine speed switch will turn on.
In order to reset the engine speed switch, turn the engine control switch to the "Off/Reset" position.
Test the engine speed switch and the PLC at the overspeed setting.
Use the following step for an engine that is rated below 930 RPM:While the engine is running, increase the engine speed to the overspeed setting. Once the engine is within 25 rpm of the overspeed setting, slowly raise the engine speed. This is done in order to determine the engine speed at shutdown. The PLC and the engine speed switch work in parallel. Either the PLC or the engine speed switch will shut down the engine in this test.Use the following step for an engine that is rated above 930 RPM:Alternately connect a 163-0096 Diagnostic and Calibration Tool to the engine speed switch in order to simulate the engine speed. See Table 1 for speeds and frequencies.
If the engine speed switch shuts down the engine due to an overspeed condition, the output 0 on the engine speed switch will illuminate.If this happens, press the "RESET" button on the engine speed switch in order to allow the engine to start again.
In order to reset the engine speed switch, turn the engine control switch to the "Off/Reset" position.
Simulate the overspeed test for the PLC.
Connect the positive lead of the frequency generator to terminal 222 and the negative lead to terminal 223. See Table 1 for speeds and frequencies.
Increase the frequency until the overspeed setting is reached.
Table 1
Rated Speed (RPM)    Overspeed Setting (RPM)    Overspeed Setting (Frequency)    75 Percent Of Overspeed Setting (RPM)    75 Percent Of Overspeed Setting (Frequency)    
720     814     3458     610     2593    
750     848     3602     636     2701    
900     1017     4322     763     3242    
930     1051     4467     788     3350    
1000     1130     4803     848     3602    
1050     1187     5045     890     3784