PGEV and PGE Locomotive Governors. Manual - part 34

PGEV and PGE Locomotive Governors 

Manual 36703 

 

 

 

122 

Woodward 

Appendix. 

Auxiliary Equipment 

 
 

Automatic Safety Shutdown and Alarms (Manual 36652) 

 
A "Lube Oil Pressure Failure Shutdown and Alarm Device" (Figure 1-2 or 1-3) 
protects the engine in the event of the loss of normal lube oil operating pressure. 
It monitors lubricating-oil pressure and is so designed that the shutdown pressure 
level becomes progressively higher as engine speed increases. 
 
A second device, a "Lube Oil Pressure Failure With Excessive Vacuum 
Shutdown and Alarm", has the added feature of monitoring the inlet side of the 
engine oil pump. Excessive vacuum will trigger the shutdown and alarm system. 
 
A time-delay feature (see Figure 1-2) allows the engine to be started without 
lubricating-oil pressure yet prevents prolonged operation if a safe pressure level 
is not reached within the preset time. 
 
A "Cooling Water Pressure Failure Shutdown" device (Figure 1-3) protects the 
engine from a drop in the normal operating pressure of the water cooling system. 
A time-delay and bypass feature is common to the system when the oil and water 
shutdown devices are used together. 
 
 

Load Control Override (Manual 36695) 

 
This mechanism overrides the normal functioning of the load-control system 
reducing generator field excitation current during engine startup, wheel slip, or 
transition. 
 
 

Manifold Air Pressure Bias Fuel Limiter (Manuals 36601 and 
36695) 

 
The fuel limiter acts to restrict engine fuel during acceleration as a function of 
manifold air pressure to ensure more complete combustion, reducing smoke to a 
minimum and improving acceleration. Two models of this device are available, a 
two-barrel model (manual 36601) or a single-barrel (inline) model (manual 
36695). While physically dissimilar in appearance and installation, they are 
essentially identical in function and achieve the same end result. Parts 
information for the oil filter used in conjunction with either model fuel limiter is 
found in Figure 7-16). 
 
Two variations of bias linkages are available for use in conjunction with either 
model fuel limiter as described above and are covered in detail in the applicable 
fuel limiter manual. 
 
 

Overspeed Valve 

 
This is a backup safety mechanism used in conjunction with a separate 
overspeed-shutdown trip. It monitors the tripping oil-supply pressure and causes 
engine shutdown in the event the tripping oil pressure drops below a safe level. 
See Figure 3-1 for a schematic representation of the valve.