to drive a common load. In such installations, one
electric control can be used for two or more
The EGB-2P (fig. 9-12) is a proportional actuator
proportional actuators wired in series with the
with a ballhead backup governor. The proportional
control's output. This furnishes the same input signal
actuator's terminal (output) shaft position is directly
to each actuator. Since each actuator receives the same
proportional to the magnitude of the output signal from
signal, their output shafts take the same position. This
the electronic control unit. The uses and functions of a
gives each engine the same fuel.
proportional actuator are different and distinct from
Externally the EGB-2P is similar in size and
integrating types of EG actuators. To have a correct
appearance to the EGB-2C actuator. Internally, each
governoring system, you must use the EGB-2P
has two sections. These are the ballhead governor and
actuator with the 2301 or similar integrating electronic
electric actuator section. The ballhead governor section
control. By comparison, the EGB-2C is an integrating
acts as a backup governor in event of failure of the
actuator with the companion EG-A control box being
electric control. The electric actuator section is
basically a proportional amplifier.
different in function and construction. The actuator
section of the EGB-2P includes feedback linkage from
Proportional actuators can be used in the same
its power piston to its pilot valve. This gives the
type of service as other actuator models. They are
proportional feature to the actuator.
particularly well suited to engines operating in tandem
Figure 9-12.--EGB-2P governor actuator.