2820A_311_F.pdf

Individual Manual Application Sheet

Technical Publications Number

2820A

Secton Applicability

SWBS Number 311 SWBS Element Title SHIP SERVICE POWER GENERATION

Section Identifier F

Equipment Functional Description

LOAD SHARING AND SPEED

CONTROL - SSDG (82406F)

CI Functional Description ESWBS Code Remarks

Planset Hulls

905-WMEC 905, 906, 907, 908, 909, 910, 911, 912, 913

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LoAo SKkXNG L SPEED Co%""'

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MODELS 8271-442,

8271-652, 8271-706, 8272-011, 8272-185, 8271-467, 8271-676, 8271-729, 8272-050

8271-472, 8271-691, 8271-826, 8272-091, This manual, 82406F, replaces 82406 and 82406A through E

WOODWARD GOVERNOR COMPANY

82406F

2301 LOAD SHARING

& SPEED CONTROL

READ THIS ENTIRE MANUAL AND ALL OTHER PUBLICATIONS PERTAINING TO THE WORK TO BE

PERFORMED BEFORE INSTALLING, OPERATING, OR SERVICING THIS EQUIPMENT. PRACTICE ALL PLANT AND SAFETY INSTRUCTIONS AND PRECAUTIONS. FAILURE TO FOLLOW INSTRUCTIONS CAN

.CAUSE PERSONAL INJURY AND/OR PROPERTY DAMAGE.

The letter designation following the manual number is changed alphabetical order when an important revision is made to the manual.

to the next letter in

TEXT CHANGES ARE INDICATED BY A BLACK LINE ALONGSIDE THE TEXT.

Woodward Governor Company reserves the right to update any portion of this publication at any time. Information provided by Woodward Governor Company is believed to be correct and reliable. However. no responsibility is assumed by Woodward Governor Company for its use unless otherwise expressly undertaken.

Woodward Governor Company, 1978 All Rights Reserved

. 0 WAR

TABLE OF CONTENTS

Section Title Section Title PagePage

Prestart Checks and Settings Static Checks

SECTION 3/OPERATION & ADJUSTMENTS .. 1 1

Introduction ....... : .................... 1 1 Initial Engine Operation ................. 1 1

Start-Up ........................... 1 1

Speed Setting Adjustment .......... 1 1 Gain & Stability Adjustment ......... 1 1 Low Idle Speed Adjustment ......... 1 1 Ramp Time Adjustment Magnetic Pickup Check Current Transformer Phasing

Check Phasing Procedure Load Gain Adjustment DE-Droop Adjustment Droop Adjustment

SECTION 4/PRINCIPLES OF OPERATION

Introduction Function Basic Theory Normal Operating Sequence

Before Starting Prime Mover Cranks or Turns Over .. 16 Ramp Switch Closes Load Application Paralleling

SECTION S/TROUBLESHOOTING

Introduction Bench Performance Check .............. 1 9 Troubleshooting Troubleshooting Procedure

SECTION 1/GENERAL INFORMATION

Introduction Description ....... :

Part Number Selection

Diesel Engines, Gas & Steam Turbines

Gasoline & Natural Gas Engines, and Steam Turbines

Magnetic Pickup Frequency References

SECTION 2/11NSTALLATION

Introduction

Power Requiretnents Environmental Precautions Location Considerations

Electrical Connections Shielded Wiring Potential Transformer

Connections Current Transformer

Connections Mode Switch (Isoch-Droop)

& Load Sharing Lines Power Supply High Supply Voltage Selector

(Optional) Ramp Switch Actuator Output Magnetic Pickup External Speed Trim Minimum Fuel Switch SPM Synchronizer Failsate Override

Installation Checkout i

2301 LOAD SHARING & SPEED CONTROL

RATED

SPEED STAOX(Tv CAIN RAMP TIME LOW IDIE SPEED LOAD CAIN DROOP DEDROOP'I 011 gold

LOAD SLG

OPEN-IDLE SPEED CLOSE FOR OPEN DROOP REMOVE

90-240 A, CLOSECIRATED MAGNETIC TRIM MINIMUM CLOSE)SM" JUMPER

VAC CT CT CT P&AAL.Lt ACTUATOR PXXUP OR o", SYNC 10 rVE&I A 0 Q A 8 c LIKES +VDC�. r4 1,1 T + INPU , JUMPER IN 1-11-1 '"'WE 1 2 3 4 5 6 1 a 9 ID it, 12 13 14 is 6 I? to 19 20 21 21 U 24 is 26 27 24 Z9 10

8240(-A-10

W _ZW_�AR )I

Figure 1-1. 2,301 Load Sharing and Speed Control

00DWAP17)

Prime Mover as used throughout this manual refers to either engines, turbines, or other types of prime movers.

PART NUMBER SELECTION

DIESEL ENGINES AND GAS TURBINES

The 8271-442 and 8271-467 are intended for use on diesel engines and gas turbines. The two are electrically identical. The 8271-467 is an 8271-442 on a backing plate.

GASOLINE, NATURAL GAS ENGINES, AND

STEAM TURBINES

The 8271-652 is recommended for carbureted gas engines. Except for slower dynamic response it is identical to the 8271-442. With a back plate the 8271-652 becomes 8271-706.

MAGNETIC PICK UP FREQUENCY

A part number prefix or its absence specifies the speed range. Choose a range that includes the magnetic pickup frequency at rated speed. See Table 1-1, which applies to all three part numbers.

Hz = (RPM) X (No. of teeth on flywheel) -. 60 seconds.

Table 1-1. Part Number Prefixes

SPEED RANGE (Hz) JUMPER

450-1350 1

B8271- 900-2700 2

8271- 1800-5400 3

C8271- 3600-10.800 4

D8271- 7200-21,600 5

2301 LOAD SHARING & SPEED CONTROLS

8271-442, 8271-467, 8271-652, & 8271-706

SECTION I

GENERAL INFORMATION

NOTE

This manual has five sections: General Infor-mation, Installation, Operation, Principles of Oper-ation, and Troubleshooting.

For information concerning special applications or other information not contained in this manual, contact Woodward Governor Company, Fort Collins, Colorado 80522, phone (303) 482-581 1.

DESCRIPTION

The 2301 Control (see figure 1 -1) is an electric governing control that provides Isochronous (con-stant speed) control with load sharing for a wide range of prime mover types and sizes. The 2301 Control is housed in a single sheet metal chassis containing a single PCI3 (printed circuit board).

There Is no internal wiring, as the terminal blocks are directly mounted to the PCB. The PC13 has circuit paths on both sides with all components mounted on the upper side. All potentiometers are accessible from the front of the chassis. The load signal jacks are also mounted on the front.

Isochronous operation provides constant engine speed for single unit operation or when two or more engines are paralleled, sharing load on an isolated bus. The optional droop operation provides speed regulation as a function of load. Droop operation allows operating a unit on an infinite bus or in parallel with engine generators using hydro-mechanical governors.

Principal control system components for a single engine-generator set include a 2301 Control, exter-nal 20 to 40 vdc power source, magnetic pickup for sensing speed, a mechanical-hydraulic proportional actuator to position the fuel metering device, and current and potential transformers for load sensing.

See figure 1-2.

INTRODUCTION

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Electrostatic charges can damage the control unless correct handling and sold-ering procedures are used.

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IDENT 2

MAGNETIC

PICKUP

PARALLELING I

LINES

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Figure 1-2. Basic 2301 System spec.ifications can be ordered from any Woodward office listed on the back cover.

Manual

25031 Part 3

25070

82444'

82510

Title

Parallel Operation of Alternators

Electric Governor Installation Guide

SPM Synchronizer 8271-609, 8271- 610, and 8271-777

Magnetic Pickups for Electric Governors

Speed Setting Potentiometers

Guide for Handling and Protection of 43027 Electronic Controls

Title

2301 Load Sharing and Speed Controls 8271-442 & 8271-467

SPM Synchronizers 8271-609 & 8271-610

Import/Export Control 8271-872

EG313 Actuator

EGB2P Governor/Actuator

82514

82715

0 0

PCB

Figure 1-3. Board Jumper Location

The speed range can be changed by moving the jumper on the bottom of the PCB. This operation requires the dc supply be disconnected from the control and that a battery powered soldering iron be used. Alternatively, an iron with the tip jumpered to Terminal 15 may be used. Failure to observe this precaution can damage the 2301 control.

REFERENCES

The product literature listed here contains infor-mation for optional use or other parts associated with these controls. These manuals and product

Product Spec.

82411

82444

82456

82516

82575

OODWART)

/VN&NVVVVVVVV%

k4��� To prevent damage to the control disconnect the battery charger from the battery before disconnect- Ing the leads from the control to the battery.

The engine, turbine or other type of prime mover should be equipped with a separate overspeed (overtemperature, or overpressure, where applicable) shutdown device(s), to protect against runaway or damage to the engine, turbine or other type of prime mover with possible per-sonal Injury or loss of life should the mechanical-hydraulic governor(s), or elec-tric control(s), the actuator(s), fuel contrails), the driving mechanism(s), the linkage(s), or the controlled device(s) fail.

POWER REQUIREMENTS

The 2301 Control requires a voltage source of 20 to 40 vdc for operating power. Provide a battery charger to maintain a stable dc supply voltage if a battery is used for operating power.

Do not exceed the allowable range for the supply voltage. Over 40 volts will damage the control. Severe voltage spikes can also damage Woodward controls.

SECTION 2

INSTALLATION

avoid extreme heat and vibration conditions. The control must not be mounted on the engine.

ELECTRICAL CONNECTIONS

Plant wiring diagram (figure 2-3) shows all external wiring connections of a typical control installation.

Be sure to follow all shielding requirements (see LOCATION CONSIDERATIONS). The following paragraphs provide additional specific wiring in-structions.

INTRODUCTION

This section contains general installation instruc-tions for the 2301 Control. Power requirements, environmental precautions and location considera-tions are included to determine the best possible location for the control. Additional information includes unpacking instructions. electrical con-nections and an installation checkout procedure.

-- IWARNING

VVIEMM

SHIELDED WIRING

All shielded cable must be twisted conductor pairs.

Do not attempt to tin the braided shield. All input control lines should be shielded. (See your plant wiring drawing for shielding requirements), This prevents picking up stray signals from adjacent equipment. Connect shield to system ground (chassis) at one point at the control end only. The end away from the control should be left open. Do not run shielded lines in a conduit with high current carrying cables.

POTENTIAL TRANSFORMER CONNECTIONS

Connect the potential transformer (PT) secondary leads to the following terminals (T): AO to T1; BO to T2; CO to T3. The PT secondary line-to-line voltage must be 90 to 240 vrms. Refer to the typical plant wiring diagram (figure 2-3).

I IWARNING

CURRENT TRANSFORMER CONNECTIONS

The standard method uses three current transfor-mers connected as shown in figure 2-3. An alternate method is the open delta connection as shown in figure 2-3. For the open delta connection, connect jumper wires between terminals 4, 6, and 8.

ENVIRONMENTAL PRECAUTIONS

I kWARNINGThe 2301 Control is designed to operate within a temperature range of -400 to 1600F. The unit may be mounted in any position provided adequate ventilation is allowed for cooling.

LOCATION CONSIDERATIONS

Consider these requirements for a control location:

adequate ventilation, space for servicing and repair, proximity to auxiliary electrical equipment, and

Personal injury and damage to the equip-ment may result It current transformers are disconnected from the burden resis-tors (terminals 4 through 9) when the engine Is running. The current transfor-mers can develope dangerously high voltages.

4ou wF�� 175 I

T 7 -

CONVERSION CHART

MM - INCH

6 0.25

56 2.20 168 6.60 175 6.90 178 7.00 349 13.75 387 15.25

2301 LOAD SHARING & SPEED CONTROL

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-to

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I.oll

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ID %0 - 2400E2__-

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� a CI., 3I I 6

6 DIA (6) '�- I

82400-A-38

Figure 2-1. 8271-442 or 8271-652 Outline Drawing

MODE SWITCH (ISOCH-DROOP) & LOAD

SHARING LINES

Connect load sharing lines through high quality, low signal, auxiliary contacts of the circuit breaker to terminals T10 (+) and T11 (-). These lines must be shielded and shields tied at one end only to chassis ground. If a mode switch at T26 and T27 is used in place of the factory jumper, connect it to a switch or relay as shown in the wiring schematic.

When the contacts at T26 and T27 are open for droop operation, the positive paralleling line, T10, is also open. These lines must be shielded and shields tied to chassis ground at the control end only.

NOTE

Droop operation is required when paral-leling with an infinite bus or units not having compatible electric governors. The Load Sharing and Speed Control can be in isochronous when used against an infinite bus with a Generator Loading Control or ImportlExport Control. The Droop signal then comes from either the Generator Loading Control or the Im-portlExport Control.

POWER SUPPLY

Connect the negative power supply lead to T13.

Connect the positive lead to T1 2. If a battery is used be sure the system includes a battery charger.

II0

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WRONG 82400-A-143

Figure 2-2. Correct and Incorrect Wiring to Battery

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WAR11114 I

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I METRIC I

WOODWAC

Controls with Internal Diodes

8271-442 8271-472 8271-652 8271-706 8271-676 8272-011 8272-091 8271-467Do Not Energize The Control Yet.

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I hWARNING

HIGH SUPPLY VOLTAGE SELECTOR

(OPTIONAL)

When operating a number of controls in load sharing applications which have separate power sources and a common return, use a high supply voltage selector. See figure 2-3. This ensures optimum load sharing accuracy and minimizes system sensitivity to noise on the power supplies. The current rating for each diodeshould be 1 amperetimes the number of grey LSSC's plus 0.4 ampere times the numberof beige LSSC's in the system. This scheme will auto-matically select the battery with the highest voltage and use it to power all units. To remove power from any control Interrupt the power to both positive and negative power supply wires.

When using the following controls, the external diode Is not necessary because it is already in the controls.

These newer controls are also identified by no label at terminal 25, and "20 to 40 vdc" at terminals 12 and

13. Older controls (which require external diodes) have "32 vdc" at terminal 25 and "24 vdc" at terminals 12 and 13. If a system has an 8271-442, an 8290-009, and an 8271-308, the 8271-442 and 8290- 009 controls should have a wire joining terminal 25 to 25. The 8271-308's terminal 25 should be left unconnected. See figure 2-3.

When using this scheme it is necessary to switch terminal 25 as well as the positive and negative power input.

Controls 8271-676, 8271-691. 8271-729, and 8271- 826 all have a notch filter which filters torsional frequencies from the engine. If the actuator output shaft isjiggling adjustthe notch filteruntil theoutput shaft stops jiggling.

LSSC

LSSC

LSSC

/I

Z

Figure 2-3. High Voltage Selector, External Diode.

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1- PP11 01

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LSSC

LSSC

LSSC

Figure 2-4. High Voltage Selector, Internal Diode

'Controls I LSSN( Iwith Internal Diodes �11 & 13i--4� - 0

Figure 2-5. High Voltage Selector, External and Internal Diode

-r< 12 1 C�-�

1 LSSC

130---:;,-

Do not use the minimum fuel option as part of any emergency stop sequence.

-I-

2501 LOAD SH&A104 a SPEED CWROL

.1 A

VA'"4 11 I I I 11 I 11 11

RAMP SWITCH EXTERNAL SPEED TRIM

Connect a SPST switch between T14 and T15. Oil pressure is often used to close the ramp switch.

External wiring must be shielded. With T14-15 open, idle speed is selected. When T14-15 close, a ramp to rated speed is started. If idle speed is not used, T14-15 must be jumpered. The Ramp Gen-erator is also disabled when T14 - T15 are jumpered.

ACTUATOR OUTPUT

Connect wire from T16 to the actuator plug pin B, and T17 to the actuator plug pin A. Be sure wires are not shorted in actuator plug, For tandem (series) actuators, follow plant wiring diagram, figure 2-4. Also see actuator bulletin for complete installation instructions. The EG3P actuator plug requires a jumper from terminals C to D.

For external speed trim, remove the jumper wire from T20 and T21. Connect a 100 ohm potentio-meter to T20 and T21 as shown in plant wiring diagram figure 2-4. This potentiometer gives ap-proximately ± 4% speed adjustment.

MINIMUM FUEL SWITCH

Connect T22 and T23 to a switch or relay contacts as shown in plant wiring diagram, figure 2-4.

Shielded wire is required. Closing external contacts between control terminals 22 and 23 will send a minimum fuel signal to the actuator.

The minimum fuel signal is intended as an optional means for normal shutdown.

I kWARNING

MAGNETIC PICKUP

Connect the magnetic pickup to T16 and T19.

These lines must be shielded.

- 341 i i - � � 30

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CONVERSION CHART

MM - INCH

I -W Is 3.34 its 7.14 234 &4* W Wo

34? IL21

82400-A-39

Figure 2-6. 8271-467 or 8271-706 Outline Drawing w/back plate

00DWAMD

A, ACTUATOR

- a No. I I I a AMMETER

I

DETAIL -

CONNECTION FOR SERIES - I

OR TANDEM OPERATION I I :MMETER

I i A , OPTIONAL CURRENT

TRANSFORMER CONNECTION

A Figure 2-7. Typical Plant Wiring Diagram a

For normal operation of the failsafe circuit, the circuit must be complete between terminals 29 and 30 with unit running.

INSTALLATION CHECKOUT

9. Optional use. Rotor to high voltage selector In SECTION

2, INSTALLATION.

10. Do not use either the minimum fuel option, or disconnect the actuator leads, or disconnect the power lo the control as part of any emergency atop sequence.

II. This option requires a balanced three photo load.

12. Remote ammoters can be used to monitor generator curr*nL Put the ammeter In series with terminal 5, 7, or 9 with polarity as shown.

SPM SYNCHRONIZER

Connect the synchronizer (optional equipment) to T23 (-) and T24 (+). Shielded wire is required.

Figure 2-7. Continued

NOTES FOR FIGURE 2-7.

1. When power lo removed from the unit for service, open the positive and negative supply leads (terminals, 12 & 13). Also. open terminal 25 It It Is used. Open terminal 11 It It Is not opened by auxiliary contact.

Prevent leads from connecting ground or shorting to.

gothsr, It not connected through a switch.

2. Remove jumper between 20 and 21, when remote speed potentiometer Is used. A high quality 100 ohm, 10 turn, potentiometer similar lo Woodward P/N 1657-537 Is recommended 100 ohms "rheostat connected" will give approximately ± 4% speed adjustment.

3. For series or tandem operation connect actuatom In series as shown (terminal 8 to A) and add jumper between control terminals 17 and 28. Place contacts on lead that Is not grounded.

4.

FAILSAFE OVERRIDE

To facilitate making static checks and trouble-shooting install a switch in place of the jumper on terminals 29 and 30. Use shielded wire when using a switch.

Defeat the magnetic pickup fallsafe by removing the jumper or opening the switch between terminals 29 and 30. When the fallsafe Is defeated and the magnetic pickup signal Is Interrupted the actuator's output shaft moves to maximum fuel position.

Defeating the failsafe during start-up can also help because the actuator's output shaft moves to maximum fuel.

WARNING

You may be killed or the equipment may be damaged It lethal high voltage develops across terminals 4 through 9. This control contains Internal burden resistors which must be connected across power source current transformers whenever the control Is operating.

5. Circuit breaker auxiliary contacts close when breaker closes. , & For Isochronous control, without the Isochronous-droop switch, make sure the jumper across terminate 26 and 27 or droop pat Is maximum cow. Remove jumper (26 lo 27) when Isochronaus-droop switch Is used.

T. Power source current transformers should be sized to produce SA secondary current with maximum generator current. Current transformer burden Is 6.5VA per phase.

S. With a balanced three phase load and unity power factor the current transformers should be wired In the correct potential tog and must be phased at the control as follows:

Phase I Potential terminal I with respect to neutral, In phase with CT terminals 4 to 5.

Phase 2 Potential terminal 2, with respect to neutral, In phase with CT terminals 6 to T.

Phase 3 Potential terminal 3, with respect to neutral, In phase with CT terminals 0 to S.

Before starting the engine-generator, perform the following checkout procedure to verify that the 2301 Control is, operational. The prestart checks consist of a visual inspection, adjustments and switch presettings. The static checks determine the operational status of the power supply and the amplifier output voltage.

[ WARNING h

PRES TA R T CHEC KS A ND SE T TINGS

1. VISUAL INSPECTION

A. Linkage between actuator and prime mover must not be loose or binding.

Refer to manual 25070 for linkage infor-mation.

WARNING

The actuator lever should be near the minimum position when the fuel or steam rack Is at the minimum position.

B. Check for correct wiring per Figure 2-4.

C. Check for broken terminals and loose terminal screws.

D. Check the magnetic pickup for signs of damage. Any discrepancy suggests replacement since the magnetic pick-up is non-repairable. Magnetic pickup gear clearance should be 0.020 to 0.040 inch.

E. The minimum voltage required, from the magnetic pickup, to operate the elec-tronic control is 1.5 vrms.

2. RATED SPEED

6. LOW IDLE SPEED - set fully CW.

7. LOAD GAIN - set fully CW.

8. DROOP - set fully CCW.

9. DE-DROOP - This adjustment is made at the factory and should not be adjusted at this time.

10. MODE SWITCH (DROOP-ISOCH) - set to desired position. For some installations only one mode is used and this switch need not be installed. In this case terminals 26, 27, and 10 may be permanently wired.

STA TIC CHECKS

Energize the 2301 Control by connecting power to T12 (+) andT13 (-). DO NOT START ENGINE until the following static checks are completed and you have read the entire procedure.

NOTE

The actuator or a 35 ohm 10 watt load must be connected across terminals 16 and 17.

1. Check terminal 28 (+) and 23 (-) for 1 0.0 1 vdc.

2. Check terminals 17 (+) and 16 (-) for 0 vdc.

When failsafe is defeated this voltage should be approximately 8 vdc. Be sure to replace the jumper on terminals 29 and 30.

3. Check the voltage at terminals 11 (+)and 13 (-). It must be approximately 10 vdc. If voltage is near zero, check that neither paralleling line is connected to battery nega-tive.

If any irregularities are found in the static checks, refer to Section 5 for troubleshooting instructions.

A. Set the RATED SPEED control approximately one turn CW from fully CcW.

B. Set the external speed trim, if used, to mid position.

3. STABILITY - set to mid position.

4. GAIN - set to mid position.

5. RAMPTIME-setfullyCCW.

OODWAPD

Read this entire procedure before starting the prime mover.

TO PROTECT AGAINST POSSIBLE

PERSONAL INJURY, LOSS OF

LIFE, and/or PROPERTY DAMAGE WHEN STARTING the engine, turbine, or other type of prime mover, BE PREPARED TO INITIATE AN EMERGENCY SHUTDOWN to protect against runaway or over-speed should the mechanical-hydraulic governor(s), or electric control(s), the actuator(s), fuel control(s), the driving mechanism(s), the linkage(s), or the control device(s) fall.

4. Start the engine.

SECTION 3

OPERATION AND ADJUSTMENTS

SPEED SETTING ADJUSTMENT

Set RATED SPEED potentiometer to rated speed while external speed trim (if used) is set at mid position.

GAIN AND STABILITY ADJUSTMENT

The object of the GAIN and STABILITY adjustment is to obtain the optimum, or desired, stable prime mover response.

Connect a dc analog voltmeter to terminals 16 and 17 (+) (actuator voltage).

Increased gain causes faster transient response.

To achieve faster response, increase GAIN (CW) to obtain a slightly unstable condition, best ob-served on the voltmeter. Adjust the STABILITY either direction as necessary to achieve stability. Step load the prime mover or close minimum fuel (terminals 22-23) momentarily to check stability.

Readjust STABILITY as necessary. If stability cannot be obtained for a transient by the STABILITY adjustment, decrease the GAIN unless stability is a slow hunt, in which case, increase GAIN.

Figure 3-1 shows engine starts (with the ramp control fully CCW) and transients at four different gain and stability settings with stable steady state running conditions. These are typical performance curves on a naturally aspirated (non-turbocharged) diesel engine.

NOTE

Optimum performance is not necessarily obtained with GAIN control at maximum stable clockwise position. In some cases, the gain must be reduced slightly to insure stability under widely varying conditions.

LOW IDLE SPEED ADJUSTMENT

1. Open the external ramp switch. Engine should decelerate to a speed set by the LOW IDLE SPEED potentiometer.

2. Adjust LOW IDLE SPEED until recommended idle speed is reached.

NOTE

Make certain that the engine speed is controlled by the LOW IDLE SPEED potentiometer in a range above the minimum fuel position (mechanical stop) of the actuator or engine fuel rack.

INTRODUCTION

This section provides information on control ad-justments and selectable parameters. It also has an initial engine operation procedure for use during initial engine startup.

INITIAL ENGINE OPERATION

START-UP

1. Complete the Installation Checkout.

2. Close ramp switch. Set the control for iso-chronous operation.

NOTE

This is for initial engine start-up only. For normal start-up, ramp switch should be open until signaled (by lube oil pressure switch or other means) to close for acceler-ation to rated speed.

3. Apply power to the 2301 Control.

SPEED

SPEED

START LOAD

ON

LOAD

OFF

A

V- V

0 IS FULLY CCW

GAIN AT 7.5 STABILITY AT 1.S 10 IS FULLY CW

Gain Is too high and stability too low. There are secondary overshoots on transients and large overshoots on starts.

�t

SPEED

-4W

- - - V

GAIN AT 7 STABILITY AT 2

Optimum performance on load transients with slight overshoot on starts.

SPEED

- k-

GAIN AT 5.5 STABILITY AT 3

Optimum performance on start with slight time extension of load transients.

Y,--

GAIN AT 4 STABILITY AT 4

Stability too high, long time to settle to rated speed.

01-

82500-A-303

Figure 3-1. Engine Performance Curve

1 2

You may be killed or Injured It the current transformers are disconnect-ed from the burden resistors (term- Inals 4 through 9) when the engine Is running. The current transformers can develop dangerously high vol-tages.

3. Check the phase wiring by momentarily shorting the phase A current transformer (CT) secondary. The load signal voltage should drop by 1/3 if the load is evenly divided among the three phases. Repeat this procedure for phase B J6 to T7) and C J8 to T9), one phase at a time.

If the load signal voltage dropped by 1/3 for each phase skip the phasing procedure. If the load signal did not drop by 1/3 or if improper load sharing is observed perform the phasing procedure.

PHASING PROCEDURE

Most paralleling difficulties are due to improper wiring of the three-phase current and potential inputs. Common errors include either wiring the voltage of one phase with the current of another phase or wiring transformers backward. If the conditions above are obtained, the phasing is correct, Proceed to LOAD GAIN ADJUSTMENT.

RAMP TIME ADJUSTMENT

Adjust the RAMP TIME to determine the rate for satisfactory engine acceleration to rated speed with minimum overshoot. Do this by trial and error, by first starting in full CW and working back CCW until the unit ramps as fast as desired.

MAGNETIC PICKUP CHECK

Check for greater than 1.0 vrms across terminals 18 and 19 during cranking, and less than 50 vrms maximum at rated speed.

CURRENT TRANSFORMER PHASING CHECK

/*%%VVV*%NNAA^%

CAUTION

Before starting phasing check, be sure potential connections OA, OB, and OC correspond to control term- Inals 1, 2, and 3.

1. In the Isochronous mode and not paralleled, load generator to as near full load as possible, with unity power factor.

2. Connect dc voltmeter leads to the LOAD SIGNAL test jacks on the control. Observe labelled polarity.

I WARNING

1. Turn LOAD GAIN potentiometer to mid posi-tion.

2. Apply a constant load. If it is not possible to use a load bank for applying a constant load, or if load varies, use two voltmeters to make simultaneous measurements of load gain vol-tage and CT input voltage.

NOTE

The power factor must be less than

0.9 for the following procedure to work.

3. Short out OB and OC CT inputs. It is important that the jumpers be no longer than 4 inches and 18 ga. or heavier. Jumper terminal con-nections must be low resistance and can be made with alligator clips.

4. Read OA CT input in vrms.

5. Read the load signal voltage at the load signal jacks.

6. Findtheratio'R'whereR= LoadSignal(vdc) OA CT Signal (vrms)

If R = +0.95, OA is correctly wired.

If R = -0.95, OA CT phasing is reversed.

If R = -0.5, OA CT is interchanged with OB or

OC.*

If R = +0.5, OA CT is interchanged with OB or OC and OB or OC CT is reversed.

It cannot be determined which phase is inter-changed with OA by testing only OA. Repeating the above tests using OB and OC should indicate which phase is interchanged with OA. If all phases yield the same result, (i.e.,R = ± 0.5 above) then the system should be shutdown and CT inputs rotated by one position (i.e.,OA to 08, OB to OC, and OC to OA). If the same results are again observed, shut the system down and again rotate the CT inputs one position.

= 1.18 = 0.94 1.25

EXAMPLE 1: OA CT connection reversed

1. With unit loaded, turn load gain potentiometer to mid position.

2. Short out OB and OC CT inputs. (Attach a jumper between terminals 6 and 7, and 8 and 9.)

3. Read OA CT input in vrms. (Measuring between terminals 4 and 5 we get v = 1.25 vac.)

4. Read the load signal voltage at the test jacks;

observe the polarity markings. (v = -1.19 vdc).

10. R= Load Signal (vdc) OB CT Signal (vrms)

This indicates OB is properly connected. We are now assured OA and OC are interchanged.

We also know that OC phasing is reversed because OB was found to be correct.

11. After shutting down the engine, reverse the phasing of OC CT (T8-T9). Then interchange OA and OC CT connections. Take care to maintain correct phasing once this phasing procedure is complete.

LOAD GAIN ADJUSTMENT

With engine operating in single unit configuration, set LOAD GAIN control for 6.0 volts measured at the LOAD SIGNAL jacks during full load. If the CT ratio does not provide 5 amperes at full load, it will be necessary to select a lower voltage. Set all other units in the system for this same voltage.

When paralleled, adjustment of the load gain potentiometer cw will cause that unit to carry less load. If stability problems occur when paralleled at this setting, reduce the- setting and set all other units for the same voltage. It may be necessary to reduce this setting to as low as three volts in cases of extremely poor system dynamics. Woodward Governor Company should be consulted in such cases.

NOTE

Reducing the load gain voltage of all units will reduce the load sharing gain.

This will result in some loss of load sharing sensitivity.

5. R= Load Signal (vdc) OA CT Signal (vrms)

-1.19 = -0.95 T 2-5

6. Since R = -0.95, we know that the CT connections to terminals 4 and 5 are reversed.

After shutting the engine down, simply dis-connect and reverse them.

EXAMPLE 2: OA interchanged with OC, OC reversed

1 . With unit loaded, turn load gain potentiometer to mid position.

2. Short out OB and OC CT inputs. Attach a jumper between terminals 6 and 7, and 8 and 9.

3. Read OA CT input in vrms. (Measuring be-tween terminals 4 and 5 we get v=1.25 vac.)

4. Read the load signal voltage at the test jacks (v = +0.62 vdc).

.5. R = Load Signal (vdc) OA CT Signal (vrms)

= 0.62 = 0.05

1.25 DE-DROOP ADJUSTMENT

6. OA CT is interchanged with OB or OC and OB or OC CT is reversed.

7. Short out OA and OC CT inputs. (Attach a jumper between terminals 4 and 5, and 8 and 9.) Open jumper between terminals 6 and 7.

8. Read OB CT input in vrms, measuring between terminals 6 and 7 (v = 1.25 v).

9. Read the load signal voltage at the test jacks (v = +1.18 vdc).

The DE-DROOP adjustment counteracts droop resulting from component tolerances. Set the system for isochronous operation at rated speed, unloaded.

road the unit to 100% (single unit operation) and adjust DE-DROOP to return to unloaded speed.

DROOP ADJUSTMENT

Adjustment of the droop potentiometer is necessary when droop mode operation of the control is required.

NOTE 1 . With the generator not paralleled, adjust the RATED SPEED POTENTIOMETER to give a speed setting above 60 Hz by the percent droop required. (Forexample, 5% droop would require raising the speed to 63 Hz). Mark the potentio-meter position and return to 60 Hz.

2. Turn the DROOP potentiometer fully cw (for maximum droop) and set the Mode Switch to droop position.

3. Synchronize the generator to the bus and parallel it to the line.

4. Return RATED SPEED potentiometer to the mark made in step 1.

5. Adjust the DROOP potentiometer ccw, decreas-ing droop, until 100% load is achieved.

Droop is usually expressed as a percent-age and calculated by:

no load speed - full load speed X 10014 = droop no load speed

For setting DROOP on an isolated load:

1 . Set Mode Switch to droop position. Adjust the control for rated speed with no load.

2. Apply load, 100% load if possible.

3. Adjust DROOP potentiometer to give the desired speed. Operating at 60 Hz, 57 Hz at full load indicates 5% droop. If only 50% loading is possible, 58.5 Hz would indicate 5% droop. See figure 3-2, Droop Adjustment.

For setting DROOP with a system operating into an Infinite bus:

60 Hz 000%

100% MAA)l IJ . ISOCHRONOUS

NOTE

It load other than 100% is desired, the speed pot will have to be set accordingly for desired percent droop. For example; at 5% droop a 50% load speed setting would be for 61.5 Hz.

57 Hz 95%t .

SPEED

I I

LOAD -- w 50% I

100%

U40U A-69

Figure 3-2. Droop Adjustment

TO PROTECT AGAINST POSSIBLE

PERSONAL INJURY, LOSS OF LIFE,

and/or PROPERTY DAMAGE WHEN STARTING the engine, turbine, or other type of prime mover, BE PREPARED TO

INITIATE AN EMERGENCY SHUTDOWN

to protect against runaway or overspeed should the mechanical-hydraulic gover-nor(s), or electric control(s), the actua-tor(s), fuel control(s), the driving mechanism(s), the linkage(s), or the control device(s) fail.

BASIC THEORY

The prime mover speed is detected with a magnetic pickup. Placed next to a gear rotating at a speed proportional to prime mover speed, the magnetic pickup generates an ac voltage whose frequency is proportional to prime mover speed. Precision circuitry converts this ac voltage into a dc voltage inversely proportional to engine speed.

The prime mover speed is set with the rated speed potentiometer on the control. The optional external speed trim potentiometer can also adjust speed.

The speed setting voltage is then compared at the control amplifier with the speed voltage.

The control amplifier then sends an appropriate voltage to the actuator. For example, if the speed

SECTION 4

0PRINCIPLES OF OPERATION

were greater than the speed setting, the control amp I if ier would decrease its output and the actuator would decrease the fuel to the prime mover.

The actuator is a prime mover mounted (usually prime mover driven) device that converts an electrical input (amplifier voltage) to a mechanical output (terminal shaft position) which positions the prime mover fuel rack.

Load sharing between two or more generator sets is accomplished via the load sensing circuitry.

Each generator's load is electronically measured continuously by its respective 2301 and compared to other units on the same bus via paralleling lines.

Continuous correction to the control loop gives load sharing.

A ramp generator allows controlled acceleration from idle to rated speed.

INTRODUCTION

This section is intended to describe in general terms what the control does and how. This dis-cussion is keyed to figure 4-2. To aid understanding, the reader is led through a normal operating sequence, which is keyed to figure 4-1.

FUNCTION

The 2301 Load Sharing and Speed Control performs two major functions-precise prime mover speed control and kilowatt load sharing between engine-generator sets. Speed is measured and compared continuously to a speed reference with necessary corrections made through the actuator to the engine fuel setting.

WARNING

The speed sensing failsafe will shut the prime mover down if the magnetic pickup signal fails.

The failsafe circuit is self-clearing when the prime mover cranks. A 1.0 volt ac signal indicates to the control that the magnetic pickup signal is correct and the failsafe section is then automatically cleared.

NORMAL OPERATING SEQUENCE

This operating sequence, from start through load application, was selected to further explain the operation of the 2301 Control. Application require-ments may require different sequences. Consult the prime mover manufacturer or generator set builder for specific details of your system.

BEFORE STARTING

Power may be applied to the control. The output voltage to the actuator will be 0 v1 due to the failsafe circuit. The superscript numbers are keyed to figure 4-1.

PRIME MOVER CRANKS OR TURNS OVER

As soon as the magnetic pickup generates about 1 vaC2, the failsafe clears and the actuator voltage goes to about BV3.

00DWAPD

. 000WAM

When the prime mover starts, it will accelerate to idle'. At this point, the governor reduces fue15 to maintain idle6.

RAMP SWITCH CLOSES

The ramp switch may be closed' by oil pressure, by crank terminator, by a timed sequence or manually. When the switch is closed the speed setting begins increasing toward rated speed.'The rate of increase is determined by the RAMP TIME adjustment. During this time, the governor controls fuel as required to maintain the speed determined by the ramp.

When the ramp ends, the engine will be at rated speed". The ramp now has no further function until the next acceleration.

LOAD APPLICATION

8 VOLTS 3

(with TYPICAL 5 8 capac

ACTUATOR

VOLTAGE

I

When the prime mover is at rated speed, load may be applied.

PARALLELING

When the generator is in phase with the bus, the breaker may be closed. An SPM synchronizer may be used to lock the oncoming unit into phase with the bus and close the breaker automatically, When the breaker is closed.10 the unit paralleling lines are connected to the system paralleling lines through breaker auxiliary contact (or preferably, relay contacts of a signal relay requiring almost zero current to establish contact, Closing of this signal relay is initiated by the breaker auxiliary contacts). At this time, the unit picks up load and the load sharing circuit sends speed bias signals to the unit to cause the load to be shared with other units on the bus.

rate control -itor)

9 10 1 000/0

ENGINE

SPEED

82400-A�68

Figure 4-1. Operating Sequence

0 VOLTS -110 TIME

-Do-TIME

82400-A-41

Figure 4-2. Block Schematic Diagram 0

A��

SECTION 5

TROUBLESHOOTING

INTRODUCTION 6. TurnRATEDSPEEDcontrolfullyCW.

7. Connect a dc voltmeter between T16(-) and T17(+) to monitor actuator voltage.

This section contains a bench performance check and a troubleshooting guide. Periodically check all the terminal screws for tightness. Check the con-dition of the wiring and shields. Keep the terminal blocks clean.

Turn on power supply.

Turn on signal generator. Set to rated magnetic pickup frequency of unit under test at 2 to 6 vrms.

MPU (frequency)= RPM X number of teelh

8.

9.

I kWARNING

10. Actuator voltage should be approximately 8 vdc.

11. Slowly turn the speed pot CCW until the actuator voltage slowly starts to decrease toward zero. This means the speed setting has just crossed below the speed (frequency) signal.

12. Decrease signal generator frequency until the actuator voltage starts to increase. This simu-lates a decrease in speed and normal control response,

13. Open the RAMP switch at T14 and T15. The actuator voltage should drop to zero, until slightly less than Idle frequency is set with the signal generator at which time the voltage will increase..

The engine, turbine, or other type of prime mover should be equipped with a separate overspeed (overtemperature, or overpressure, where applicable) shut-down devIce(s), to protect against run-away or damage to the engine, turbine or other type of prime mover with possible personal Injury or loss of life should the mechanical-hydraulic gover-nor(s), or electric control(s), the actuators), fuel control(s), the driving mechanism(s), the linkage(s), or the controlled device(s) fall.

BENCH PERFORMANCE CHECK

The following procedure simulates operating conditions for the 2301 Control. Before beginning the bench check, visually check the chassis, terminal block and printed circuit board for damage.

14. Close the RAMP switch. The actuator voltage should then increase to maximum voltage, approximately 8 vdc.

15. Turn off the signal generator or open the MPU lead(s). The actuator voltage will drop to zero, verifying the failsafe circuit is working.

(Jumper from T29 to T30 must be installed.)

16. Turn on the signal generator or connect MPU lead(s) and move signal generator frequency from below to above rated frequency to simulate a speed increase. The actuator vol-tage should decrease toward zero. Move frequency below rated speed. Actuator voltage will increase.

17. Close the MINIMUM FUEL switch between T22 and T23. Actuator voltage should drop to Ov.

NOTE

The load sensing circuitry is not included in this procedure because of the 3 phase inputs required.

Check this under actual load condi-tions.

1 . Connect a 24 vdc power supply to T12(+) and T13(-) and switch it off.

2. Connect a closed SPST switch between T14 and T15 (ramp switch).

3. Connect a 35 ohm, 10 watt resistor between T16 and T17. This simulates the actuator coil.

4. Connect an ac signal generator to T18 and T19. This simulates the magnetic pickup.

5. Connect an open SPST switch between T22 and T23. This simulates the minimum fuel switch, TO PROTECT AGAINST POSSIBLE

PERSONAL INJURY, LOSS OF LIFE,

and/or PROPERTY DAMAGE WHEN STARTING the engine, turbine, or other type of prime mover, BE PREPARED TO

INITIATE AN EMERGENCY SHUTDOWN

to protect against runaway or overspeed should the mechanical-hydraulic gover-nor(s), or electric control(s), the actu-ator(s), fuel control(s), the driving mechanism(s), the linkage(s), or the control device(s) fall.

SYMPTOM CAUSE . REMEDY

Engine will not start - Voltage polarity reversed. Reverse actuator leads at T16 and T1 7.

actuator not moving to start fuel position Actuator not responding to input signal If there is a voltage output at the Control, from control. but the actuator does not move, the wiring to the actuator should be checked

NOTE NOTE for opens or shorts. With the EG3P actuator, remember that terminals C and

If the actuator moves to The hydraulic actuator must D of the mating plug should be jumpered.

start position, a problem have oil pressure and gear with the prime mover rotation to operate (respond). Make resistance checks at the actuator.

fuel supply is indicated. Coil resistance is approx. 35 ohms. (Read with leads at TI 6 and TI 7 disconnected.)

Check actuator and linkage for proper installation and operation. Problems may be oil supply, rotation, insufficient drainage, linkage, worn actuator components or improper adjustment.

No input supply voltage. Check 2301 Control T12(+) and T13(-) for 20 to 40 vdc.

If no output voltage. Check T28(+) and T30(-) for 10 vdc.

Speed setting adjustment. SPEED setting may be lower than cranking speed. Increase SPEED setting (CW).

wiring (see figure 2-3), solder connections, switch and relay contacts and input and output con-nections are correct and in good order. Make the checks in the order indicated. Various system checks assume that the prior checks have been properly made.

I WARNING k

TROUBLESHOOTING ,

The following troubleshooting guide is an aid to isolate the trouble to the control box itself, the actuator, the plant wiring or elsewhere. Trouble-shooting beyond this level is recommended ONLY when a complete facility for control testing is available.

/VVVVVV%%%A1V1V\

� CAUTION �

%VVAAA^^AA&A&1*"

The control can be damaged with the wrong voltage. When replacing a control check the power supply, battery, etc. for the correct voltage.

TROUBLESHOOTING PROCEDURE

Table 5-1 is a general guide for isolating system problems. This guide assumes that the system

Table 5-1. Troubleshooting

00DWARD

.VVUQVVWARI

SYMPTOM I CAUSE I REMEDY

LOW IDLE SPEED setting may be set Adjust LOW IDLE SPEED potentiometer too low. CK

MINIMUM FUEL contacts closed. See Check T22 and T23. Must be open for nor- "Minimum Fuel Switch" in Section 2. mal operation.

Magnetic pickup signal not clearing lailsafe. Check wiring for proper connection .

Check shields for proper installation.

Magnetic pickup not spaced property-check for at least 1.0 vac at terminals 18 and 19 during cranking. If less than 1.0 vac, magnetic pickup may be spaced too far from gear. Check for metal chips on end of pickup.

Failsale feature may be disabled by removing jumper between terminals 29 and 30.

WARNIN

TO PROTECT AGAINST POSSIBLE

PERSONAL INJURY, LOSS OF

LIFE and/or PROPERTY DAMAGE when starting the engine, turbine or other type of prime mover, BE

PREPARED TO INITIATE AN

EMERGENCY SHUTDOWN to protect against runaway or over speeding should the mechanical-hydraulic govennor(s), electric control(s), actuators), fuel control(&), driving mechanisms), IInkage(s), or controlling device(s) fall.

If no voltage is present, pickup is open circuited. Make resistance check with leads disconnected from control. Should be about 100 to 300 ohms.

Faulty speed setting potentiometer. Verifying that II optional external speed trim is not used. terminals 20 and 21 are jumpered.

With power OFF check speed potentiometers with an ohmmeter.

I

I

TABLE 5-1 (con't.)

Enginewill notstart-actuator not moving to start fuel position.

(cont.)

,AAAA&VvVAA/1A

TION J

It adjusting SPEED setting CW does not produce the correct amplifier output, return SPEED setting lo normal start position-less than 2 turns from full CCW.

Faulty 2301 Control. Replace.

TABLE 5-1 (con't.)

SYMPTOM CAUSE REMEDY

Prime mover overspeeds only Ramp adjustment. Increase RAMP TIME (CW). This on starts. decreases acceleration rate (from idle to r;;tpdl- RATED SPEED setting too high. Turn RATED SPEED setting CCW until governor takes control at rated speed.

Amplifier adjustment. Amplifier may be adjusted for sluggish operation causing overspeed on start.

Adjust GAIN and STABILITY for fastest stable response, (Usually about 1/2 GAIN turn CW on gas engines and 3/4 GAIN turn CW on diesel engines, each with 1/2 STABILITY turn CW.)

Determine if engine malfunction. Verify that fuel rack is not binding and linkage properly adjusted. It may be necessary to determine if the fuel rack is quickly following the actuator input voltage.

Verify proper operation of overspeed protection devices.

System grounding. Check for proper shielding and system ground. It is preferred that the input supply voltage be grounded.

2301 Control If the Control does not cut back the actuator voltage [TI6(-), T1 7(+)] until the SPEED setting is completely CCW (or does not reduce fuel at any position), the 2301 Control may be faulty. If the voltage is cut back, look for a problem in the I inkage or actuator.

Prime mover overspeeds Prime mover Check for proper operation of engine fuel after operating at rated speed system.

for some time.

Magnetic pickup and 2301 Control. Check the magnetic pickup output voltage at speeds above idle - at least 1.0 vrms. If magnetic pickup should fail and the Failsafe circuit is disabled (or faulty), the 2301 Control will call for maximum fuel.

2301 Control amplifier Control the engine manually between idle and rated speed and adjust the RATED SPEED setting fully CCW. If the output voltage is not zero, replace the Control.

Low speed is not regulated by The LOW IDLE SPEED setting may be LOW IDLE SPEED potentio- below the minimum fuel position of the meter. actuator or engine minimum fuel stop. In this case, the output voltage to the actuator will be zero.

The engine will be maintained at the minimum fuel position by the actuator or the engine minimum fuel stop. The conditions above indicate that the engine minimum fuel position should be 0

00DWARD

TABLE 5-1 (con't.)

Low speed Is not regulated by decreased by linkage adjustment (diesel LOW IDLE SPEED potentio- engine) or low idle set screw (gas engine) meter, (conQ or the LOW IDLE SPEED setting of the ramp raised. 11 the above action does not correct the problem, the 2301 ramp circuitry may be faulty.

NOTE

On carbureted engine. the minimum fuel stop RPM setting will vary with engine tempera ture. An improper cold selling may give interference with the LOW IDLE SPEED setting when the engine is hot.

LOW IDLE SPEED potentiometer If adjustment of the LOW IDLE SPEED potentiometer causes erratic behavior.

replace the control.

Prime mover does not de- Faulty ramp switch Check ramp switch contacts-remove celerate when ramp switch is wires from terminals 14 and 15. Engine opened. should decelerate.

2301 Control ramp circuitry If the ramp switch is operative, loss of ramp control may be due to a faulty circuit.

A faulty ramp may maintain itself in the accelerate position with the ramp switch open.

In general, adjustment of LOW IDLE SPEED will vary the speed of the engine with the ramp switch in the decelerate (open) position. Adjustment of LOW IDLE SPEED should not aflect prime mover speed when the ramp is in the accelerate condition.

The speed setting controls have sufficient range lo override the ramp and bring the engine speed up to rated while still In the decelerate mode (either by defect or switch- Ing). Therefore, a ramp switch that Is Intermittent may cause the engine to overspeed 11 the RATED SPEED setting Is adjusted for rated speed with T1 4 and 1 S open.

Prime mover will not stabilize 2301 Control Adjust GAIN and STABILITY per Section at rated no load speed. The 3, Initial Prime Mover Operation.

instability may occur at no load or It may vary with load. Speed setting controls If adjustment of external speed trim causes instability, check potentiometer with ohm-

. OODWAPr)

SYMPTOM I CAUSE I REMEDY I

Primemoverwillnot stabilize at rated no load speed. The in-stability may occur at no load or it may vary with load.

(cont.)

meter for erratic behavior (turn power off).

Use non-lubricating electrical cleaner it necessary. It internal speed potentiometer is faulty, replace control.

Necessary external wires not properly shielded.

Electrical noise, caused by wiring carrying an ac voltage. stray magnetic fields I 'rorn transformers, etc., can be picked up by improperly shielded wire.