Manifold Air Pressure Limiter; Speed/Load Reference And Ramps; Speed Reference And Ramp Functions - Woodward 2301D Installation And Operation Manual

Manual 26247
The Manifold Air Pressure (MAP) Limiter sets the fuel limit based on the air
pressure in the engine manifold. This fuel limit prevents overfueling when air
pressure is low. A five breakpoint pressure curve is available. Setting up this
limiter will also prevent excessive smoke. The fuel limits are in percent fuel
demand.
An overload switch can be used to indicate that the engine is near the maximum
manifold air pressure limit. Setting up the MAP limiter see service menu M**Fuel
Limiters 2/2**.

Speed/Load Reference and Ramps

The 2301D control provides local control with discrete inputs for raising and
lowering speed/load. For remote speed/load setting, the control provides a
remote reference analog input. Input functions are enabled as follows:

Local Speed/Load Reference Raise/Lower discrete inputs control the speed
ramp inputs when the CB Aux input is open.

Remote Speed/Load Reference setting is enabled when the Raise
Speed/Load and Lower Speed/Load contacts are both closed, the Rated
contact is closed, and Remote Reference input is selected as Speed
Reference setting or as Baseload reference setting.

Speed Reference and Ramp Functions

This section describes the operation of the speed reference and ramp functions
and their relation to each other. Read this section carefully to be sure your
sequencing provides the proper operating modes.
The control provides start, idle, lower limit, raise limit, and rated set points, accel
and decel times, and raise and lower rates, for local operation. Accel time
determines the time required for the engine to ramp from start to idle speed and
from idle to rated speed. Decel time determines the time required for the engine
to ramp from rated speed to idle speed. Raise and lower rates determine how
fast speed is increased or decreased by raise and lower discrete input
commands.
The Start Speed can be enabled for applications which need this function (e.g.,
spark gas recip engines).The start speed set point provides a speed reference
above cranking speed but below the speed achieved with the start fuel limit
setting (light-off speed). This function is configurable. The default has this
function disabled. When configured TRUE, the Start reference is selected, by
control power-up, engine not running, or engine cranking. The Start reference is
the speed reference until the engine starts. After the engine speed exceeds the
start speed set point the speed will accelerate by a controlled ramp to the
reference selected by the Idle/Rated contact input. This may not be the desired
mode of operation, so be sure to understand the implications of operating the
control in this manner.
Woodward

Manifold Air Pressure Limiter

2301D/2301D-EC Digital Control
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