The Woodward 2301D controls load sharing and speed of generators driven by diesel or gaseous engines. (These power sources are referred to as “prime movers” throughout this manual.) The 2301D is a microprocessor-based digital control designed to include the functions of and be compatible with 2301A load sharing controls. The increased flexibility of software allows the 2301D to include control functions that required additional equipment in previous versions of 2301A control systems. The 2301D therefore is suitable for upgrading existing control systems or increased functionality in new installations.

The control is housed in a sheet-metal chassis and consists of a single printed circuit board. The 2301D is set up and configured through an external computer connected at the 9-pin connector at the front of the control. The configuration software is supplied with each control.

The 2301D provides control in either isochronous, droop, or base load. The 2301D will allow for soft load transfer when being added to or removed from a bus.

The isochronous mode is used for constant prime mover speed with:

Single prime mover operation or Two or more prime movers controlled by Woodward load sharing control systems on an isolated bus

The droop mode is used for speed control as a function of load with:

Single prime mover operation on an infinite bus or Parallel operation of two or more prime movers

The base load mode provides constant load level operation against a bus with the load controlled by the 2301D.

The load setting is set by a fixed reference,

or an external input analog input,

or external contact control of the reference.

The 2301D Control Hardware includes:

1 Load Sensor

1 Actuator Driver

1 MPU Speed Sensor

1 Configurable Analog Output

2 Configurable Analog Inputs

8 Discrete (Switch) Inputs

4 Discrete (Relay Driver) Outputs

The following is an example of the typical hardware needed for a 2301D system controlling a single prime mover and generator:

A 2301D electronic control

An external 18 to 40 Vdc power source

A speed-sensing device

A proportional actuator to position the fuel-metering device and

Current and potential transformers for measuring the load carried by the generator

The engine and generator synchronous speed (50 or 60 Hz Generator Frequency) needs to be within 300 to 3600 rpm. The frequency from the magnetic pickup must be within the range of 100 to 20 000 Hz at rated speed. The 2301D speed range needs to be configured using an external computer during installation.

These 2301D controls operate with an input of 18 to 40 Vdc.

Applications

Because of the configuration software available in the 2301D hardware, application variations can now be selected using an external computer. Changing the application to accommodate engine speed range, gear teeth, and selection of forward or reverse acting actuator is a matter of software setup rather than changing hardware. See Chapter 3 to enter control set points.

The 2301D Control can be configured for forward- or reverse-acting applications. In reverse-acting systems, the actuator calls for more fuel when the actuator voltage decreases. Complete loss of voltage to the actuator will drive the actuator to full fuel. This allows a backup mechanical ballhead governor to take control rather than shut down the prime mover as would a direct-acting system.

Control Options

Here is a brief summary of programmable options in addition to speed range and actuator type:

1.Actuator current range 0–20 mA, 4–20 mA, 0–200 mA.

2.Speed trim with external raise and lower switches. Tunable rates.

3.External setting of analog speed reference input or an external analog base load reference.

4.Multiple dynamics options—  single dynamics setting selection of 2 sets of dynamics switched with Circuit Breaker Aux input  5 slope gain settings  error window gain ratio

5.Start fuel limiter

6.Analog output

7.Discrete outputs

Woodward application engineers are always available to assist you in selection of the correct control for your system, or to answer questions concerning control installation, operation, or calibration. Contact any Woodward office.

Installation

Introduction

This chapter contains general installation instructions for the 2301D control. Power requirements, environmental precautions, and location considerations are included to determine the best location for the control. Additional information includes unpacking instructions, electrical connections, and an installation check out procedure.

Unpacking

Before handling the control, read page iv, “Electrostatic Discharge Awareness”. Be careful when unpacking the electronic control. Check the control for signs of damage such as bent or dented panels, scratches, and loose or broken parts. If any damage is found, immediately notify the shipper.

Power Requirements

The 2301D control requires a voltage source of 18 to 40 Vdc, with a current capacity of at least 900 mA for operating power. If a battery is used for operating power, an alternator or other battery charging device is necessary to maintain a stable supply voltage.

Location Considerations

This product is intended for installation in a “closed electrical operating area” or in an enclosed industrial control cabinet. Consider these requirements when selecting the mounting location:

1.Adequate ventilation for cooling

2.Space for servicing and repair

3.Protection from direct exposure to water or to a condensation-prone environment

4.Protection from high-voltage or high-current devices, or devices which produce electromagnetic interference

5.Avoidance of vibration

6.Selection of a location that will provide an operating temperature range of  –40 to +70 °C (–40 to +15)

7.The control must NOT be mounted on the engine.

Electrical Connections

All inputs and outputs are made through screwless spring-actuated terminal blocks. For EMI reasons, it is recommend that all low-current wires be separated from all high-current wire.

The spring clamp can be actuated by using a standard 2.5 mm or 3/32 inch flat bladed screwdriver. The terminal blocks accept wires from 0.08–4 mm² (27–12 AWG). Two 18 AWG or three 20 AWG wires can be easily installed in each terminal. Wires for the fixed mounted power terminals should be stripped 5–6 mm (0.22 inch) long.

Shields and Grounding

An individual shield termination is provided at the terminal block for each of the signals requiring shielding. All of these inputs should be wired using shielded, twisted-pair wiring. The exposed wire length beyond the shield should be limited to one 25 mm (1 inch). Relay outputs, contact inputs, and power supply wiring do not normally require shielding, but can be shielded if desired.

The 2301D is designed for shield termination to earth ground at the control. If intervening terminal blocks are used in routing a signal, the shield should be continued through the terminal block. If shield grounding is desired at the terminal block, it should be ac coupled to earth. All other shield terminations except at the control should be ac coupled to earth through a capacitor. A 1000 pF, 500 V capacitor is sufficient. The intent is to provide a low impedance path to earth for the shield at frequencies of 150 kHz and up. Multiple direct connections of a shield to earth risk high levels of current to flow within the shield (exception, see note below on cabinet installations).

Shields can be grounded at both ends (2301D and load) if the cable length is sufficiently short (i.e. within a cabinet) to prevent ground loop current in the shield.

Potential Transformer Connections

Connect the potential transformer secondary leads to the following terminals:

Phase A to terminal 1 

Phase B to terminal 2 

Phase C to terminal 3

The potential transformer secondary line-to-line voltage must produce 90 to 120 Vac or 200 to 240 Vac. Refer to the plant wiring diagram, Figure 1-2.

Current Transformer Connections

The standard method of connecting the current transformers is shown in the plant wiring diagram, Figure 1-2. An alternate method is the open delta connection shown in the insert in the plant wiring diagram.

Load Sharing Lines

The Load Sharing Lines provide an analog communication path between compatible controls. The 2301D provides an internal relay for connecting the Load Sharing Signal to the internal circuitry at the appropriate times. When the internal relay is closed, a green LED will illuminate between terminals 9 and 10. Because the load-sharing-line relay is contained in the control, no relay is required between the control and the load-sharing-line bus. Use shielded cable and connect the load-sharing lines directly to terminals 10(+) and 11(–). Connect the shield to terminal 12. When all controls in the system are of the 2301D or 2301A types, the shields may be connected continuously between controls. When load sharing with different controls, do not connect the shields at the point where connections are made to the load-sharing-line bus. The droop contact for selecting droop or isochronous operation is wired in series with the circuit breaker auxiliary contact between terminal 34 and terminal 28 (see CB Aux/Droop contact).

When running a single unit on an infinite bus with an external load control device, terminals 34 and 37 must be connected to terminal 28 to connect the Load Matching Circuit to the load-sharing lines. The load-sharing lines must be wired to the external load control device. The circuit-breaker auxiliary contact will then be connected to this device and not to the 2301D.

Power Supply

Run the power leads directly from the power source to the control, connecting the negative lead to terminal 46, and the positive lead to terminal 45.

When power is applied, the 2301D begins performing internal memory tests to ‘boot-up’ the processor, which takes approximately 30 seconds to complete. The CPU Status LED between terminals 27 and 28 remains on during this boot-up. The control will remain in I/O lock and will not control the prime mover until the boot-up is complete. For systems requiring fast start functions, it will be necessary to continuously power the 2301D.