2301A Speed Control

Applicatons

The 2301A Speed Control controls the speed or load of diesel or gas engines, or steam or gas turbines. The unit provides control in the isochronous mode, with droop available through an externally wired potentiometer. The isochronous mode is used for constant speed of the controlled prime mover as long as it is able to provide power to satisfy the load.

The 2301A Speed Control is compatible with Woodward SPM-A synchronizers, load sensors, and other power generation controls. These controls can be added to the system at any time, using the auxiliary or SPM inputs to the 2301A Speed Control. The 2301A Speed Control is available for forward- or reverse-acting applications, and can be used with single or tandem actuators. High voltage models accept 88 to 132 Vac or 90 to 150 Vdc, and low voltage models accept 10 to 40 Vdc supply for control power.

2301A Speed Controls are also available with 4–20 mA speed-setting input (see product specification 02301).

Two Set Speeds
The control has potentiometer-set Low Idle and Rated Speed settings which are selected with a switch.

Description

The 2301A Speed Control is housed in a sheet-metal chassis and consists of a single printed circuit board. All potentiometers are accessible from the front of the chassis.

Speed range is set by an internal DIP switch inside the aluminum cover of the control. Speeds are based on the frequency of a sensed gear (not necessarily engine rpm).

Speed Trim
A speed trim potentiometer or digital reference unit may be connected to the control to adjust prime-mover speed from a remote location.

Minimum Fuel
A switch may be wired to the control to call for minimum fuel to the prime mover. This contact is used for normal shutdown.

Failed Signal Circuit
The 2301A Speed Control constantly monitors the signal from the magnetic pickup. Should the signal be below a minimum threshold, the control sends a minimum-fuel signal to the actuator. This circuit may be overridden while starting slow-cranking engines.

Special Features

Start Fuel Limit
A special circuit in the control provides a limit to the maximum fuel setting while an engine is starting. This feature helps limit exhaust smoke and engine damage.

Ramp Times
Acceleration time from low idle to rated speed may be adjusted from 1 to 22 seconds. The ramp time from rated to idle is always less than 1 second, regardless of the setting of the ramp-time potentiometer.

Reset, Gain, Actuator Compensation
Three adjustments are available to permit accurate, responsive engine control. The GAIN control adjusts response time to transient load changes. RESET adjusts the overshoot and undershoot which occurs in response to load swings. ACTUATOR COMPENSATION sets dynamic response time within a 0 to 500 millisecond range to match the time constant of the fuel system.

Power Supply
2301A Speed Controls accept either a high- or a low-voltage power source. The low-voltage model operates on 10 to 40 Vdc, and the high-voltage model operates on either 88 to 132 Vac or 90 to 150 Vdc.