Related Manuals for Basler SR4A
Summary of Contents for Basler SR4A
- Page 1 INSTRUCTION MANUAL VOLTAGE REGULATOR Model: SR4A & SR8A Part Number: 9 0177 00 XXX Publication Number: 9 0177 00 990 Revision: 09/97...
- Page 2 INTRODUCTION This manual provides information concerning the operation and installation of a SR4A & SR8A Voltage Regulator. To accomplish this, the following is provided. • Specifications • Functional Description • Installation Information • Operation • Maintenance WARNING TO AVOID PERSONAL INJURY OR EQUIPMENT DAMAGE, ONLY QUALIFIED PERSONNEL SHOULD PERFORM THE PROCEDURES PRESENTED IN THIS MANUAL.
- Page 3 © 1997, Basler Electric Co., Highland, IL 62249 September 1997 CONFIDENTIAL INFORMATION OF BASLER ELECTRIC COMPANY, HIGHLAND, IL. IT IS LOANED FOR CONFIDENTIAL USE, SUBJECT TO RETURN ON REQUEST, AND WITH THE MUTUAL UNDERSTANDING THAT IT WILL NOT BE USED IN ANY MANNER DETRIMENTAL TO THE INTEREST OF BASLER ELECTRIC COMPANY.
-
Page 4: Table Of Contents
Field Flashing................... 4-4 Parallel Operation ..................4-4 SECTION 5.0 MAINTENANCE, REPLACEMENT PARTS AND TROUBLESHOOTING ................5-1 Preventive Maintenance ................5-1 Corrective Maintenance................5-1 Operational Test ..................5-1 Replacement Parts .................. 5-2 Component Location and Identification ............ 5-2 SR4A Replacement Parts ................ 5-3... - Page 5 CONTENTS - Continued SECTION 5 MAINTENANCE, REPLACEMENT PARTS, AND TROUBLESHOOTING - Continued SR8A Replacement Parts ................5-3 Wiring Diagram ..................5-4 Warranty and Repair Service ..............5-5 Troubleshooting..................5-5 Tr oubleshooting Chart ................5-6...
-
Page 6: General Information
GENERAL INFORMATION 1-1. DESCRIPTION a. The SR4A and SR8A Voltage Regulators precisely control the output voltage of an ac electric generating system by controlling the amount of current supplied to the exciter (or generator) field. This includes brushless rotary exciters, brush type rotary exciters or direct excitation into the generator field of machines within the regulator's power rating. -
Page 7: Optional Features
Table 1-1. Electrical Specifications (con’t). <17 mS on 60 Hz systems; <20 mS on 50 Hz systems. Response Time: ±10% on nominal. Voltage Adjust Range: 60 Watts Power Dissipation (Max): ±1/2% for a 40°C (104°F) change. Temperature Coefficient: Table 1-2. Physical Specifications. Operating Temperature -55°C (-67°F) to +70°C (+158°F). -
Page 8: Accessories
1-4. ACCESSORIES a. The following is a partial list of accessories that are available for use with the SR4A and SR8A Voltage Regulators. Underfrequency protection. Excitation support systems. EMI suppression filters. Low and medium voltage power isolation transformers. Paralleling current transformers. -
Page 9: Typical Model Number
S R 4 A M O D E L A N D P O W E R R A T I N G P A R A L L E L P R O V I S I O N S V O L T A G E B U I L D - U P P R O V I S I O N S S I N G L E - P H A S E S E N S I N G E N C L O S U R E... - Page 10 The following styles are available on a special order basis. Sample Model Number SR8A A-For use A-Surface 1-No parallel A-No relay. B-Cover. 2-Voltage on all brush- mounted. provisions. Selectable 1- adjust type and B-Build-up phase rheostat most 2-Parallel relay. sensing. internally brushless provisions...
-
Page 11: Principles Of Operation
SECTION 2 PRINCIPLES OF OPERATION 2-1. FUNCTIONAL CIRCUITS Refer to the Block Diagram, Figure 2-1. The voltage regulator senses the generator voltage, com- pares a rectified sample of that voltage with a reference diode (zener) voltage and supplies the field current required to maintain the predetermined ratio between the generator voltage and the reference voltage. -
Page 12: Parallel Compensation
support. See Figure 3-2 for a typical interconnection diagram. This scheme uses the other contact on the buildup relay to connect dc voltage from the exciter armature directly to the exciter field. As an alternative, the regulator could be used as described in paragraph 2-3a. with an excitation support system accessory. - Page 13 (7) When a leading power factor (capacitive) load is applied to the generator, the voltage across R25 becomes out of the phase with the sensing voltage and the combined vectors of the two voltages results in a smaller voltage being applied to the sensing rectifiers, then the regulator reacts by increasing the generator voltage.
-
Page 14: Installation
SECTION 3 INSTALLATION 3-1. MOUNTING The voltage regulator will operate when mounted in any position, however, it should be vertically mounted to obtain optimum cooling when operating near its full rated output. The regulator can be mounted in any location where the ambient temperature does not exceed its ambient operational limits. -
Page 15: Interconnection
3-2 INTERCONNECTION CAUTION Meggers and high potential test equipment must not be used. Incorrect use of such equipment could damage the semiconductors contained in the regulator. Figure 3-2. Voltage Adjust Potentiometer (P/N 03456). Figure 3-3. Paralleling Potentiometer (P/N 03469). - Page 16 (terminals 3 and 4). (3) SR4A & SR8A Voltage Regulators are factory preset for 120 Vac sensing voltage. If the sensing voltage needs to be changed for your installation, perform the following steps.
- Page 17 (2) The dc resistance of the field to which the regulator is connected (terminals F+ and F-) must be equal to, or greater than, 9 Ω for an SR4A and 18 Ω for an SR8A. If the resistance is less than the specified minimum, a resistor must be added in series with the field.
-
Page 18: Brush Type Rotary Exciter Interconnection
Figure 3-4. Brush Type Rotary Exciter Interconnection. (2) When the generator output voltage is different than the preceding values and exceed the values specified in Table 1-2, a power transformer must be used to match the generator voltage to the regulator input. -
Page 19: Parallel Compensation
Figure 3-5. Brushless Type Rotary Exciter (or Static Exciter) Interconnection. (3) If the field or field flashing circuit is grounded, a power transformer must be used to isolate the regulator input from ground. 3-3. PARALLEL COMPENSATION (Terminals 1 and 2) a. -
Page 20: Reactive Droop Compensation (Droop)
supplies sensing voltage to regulator terminal E2. For single-sensing phase models it must be installed in the line of the three-phase generator that does not supply sensing to the regulator. c. Figures 3-4 and 3-5 show the correct CT polarity for A-B-C phase rotation sequence. If the phase rotation sequence is A-C-B, the CT's secondary leads must be interchanged. - Page 21 )LJXUH 5HDFWLYH 'LIIHUHQWLDO &URVVFXUUHQW &RPSHQVDWLRQ &7 ,QWHUFRQQHFWLRQ...
-
Page 22: Top View Of Voltage Regulator
Figure 3-7. Top View of Voltage Regulator... -
Page 23: Operation
4-1. GENERAL The initial operating procedures are outlined in paragraph 4-6 through 4-7 and should be reviewed before operation is attempted. WARNING All SR4A and SR8A Voltage Regulators are shipped factory preset for 120 Vac sensing. 4-2. OPERATION AT REDUCED SPEEDS... -
Page 24: Adjustments
CAUTION To avoid high voltage arcing, the field circuit must never be opened during operation. Also a shutdown circuit using field discharge resistors in the exciter field circuit should not be used. Safe shutdown can be accomplished by interrupting regulator ac power to regulator terminals 3 and 4. - Page 25 (1) Overvoltage (+20% or more) - If this condition occurs, open the shutdown switch immediately and/or stop the prime mover. Determine the cause of overvoltage. If necessary, refer to the troubleshooting chart. (2) No voltage build Up - If this condition exists, field flashing may be required, refer to para- graph 4-7.
-
Page 26: Field Flashing
4-7. FIELD FLASHING a. The following procedures is for use on systems where the generator voltage does not build up and no field flash provisions are incorporated. (There is usually sufficient residual magnetism to allow the generator voltage to build up without additional flashing circuit.) b. - Page 27 (a) Place each set in operation in accordance with paragraph 4-6a. (b) Verify the paralleling CT secondary is not shorted. (Unit parallel switch in PARALLEL position.) (c) Apply 25 to 100% unity power factor load to the set under test. Generator voltage should not change more than 1% and the frequency should decrease if the governor is set for droop operation.
- Page 28 (g) Adjust its speed slightly higher than that of No. 1's. (h) Observing the synchroscope (or lights), close the circuit breaker (No. 2), when the set is in phase with No. 1. (i) Immediately after closing the breaker, verify the indication on the ammeter for set No. 2. They should read well within the rating of the generator.
- Page 29 NOTE Sometimes a stability problem or fighting of these two high gain control systems (governor and voltage regulator) causes paralleling problems that cannot be isolated using manual voltage control.
-
Page 30: Maintenance, Replacement Parts And Troubleshooting
Figure 5-1. Operational Test. a. Move the wire on the sensing transformer (T1) to the terminal listed below: SR4A: Move to 120 V tap. SR8A: Move to 240 V tap. b. Adjust the voltage stability potentiometer (R4) fully counter-clockwise (CCW). -
Page 31: Replacement Parts
The following figure (Figure 5-2) and tables (Table 5-1 and 5-2) contains only those parts and assemblies which are maintenance significant. Figure 5-3 shows the wiring diagram. When ordering replacement parts, from Basler Electric always specify description of the item, the part number, and the quantity. Figure 5-2. Component Location and Identification. -
Page 32: Sr4A Replacement Parts
Figure 5-1 Reference Basler Part Legend No. Designation Number Description 9 0177 09 100 SR4A - A Circuit Board Assembly 9 0177 09 108 SR4A - E Circuit Board Assembly CR11,CR12 06899 Silicon Controlled Rectifier CR8, CR9, CR13, CR14, 02677... - Page 33 Figure 5-3. Wiring Diagram...
- Page 34 5-4. WARRANTY AND REPAIR SERVICE a. Basler SR4A and SR8A are warranted against defective material and workmanship for 18 months from the date of shipment from our factory. Units submitted for warranty repair should be returned to the factory in Highland, Illinois, freight prepaid, with complete description of the installation (See Attachment A) and the reported troubles.
- Page 35 Table 5-3. Troubleshooting Chart MALFUNCTION TEST OR INSPECTION CORRECTIVE ACTION 1. VOLTAGE DOES NOT BUILD UP TO RATED VALUE. Step 1. Check for low residual voltage and/or incorrect polarity relationship between exciter output and generator field. If either condition exists, flash the generator field. If neither condition exists, proceed to Step 2.
- Page 36 Table 5-3. Troubleshooting Chart - Continued. MALFUNCTION TEST OR INSPECTION CORRECTIVE ACTION 1. VOLTAGE DOES NOT BUILD UP TO RATED VALUE - Continued. Step 8. Verify that the exciter wiring is correct. If the exciter wiring in incorrect, reconnect the exciter. If the exciter wiring is correct, proceed to step 9.
- Page 37 Table 5-3. Troubleshooting Chart - Continued. MALFUNCTION TEST OR INSPECTION CORRECTIVE ACTION 3. VOLTAGE HIGH AND UNCONTROLLABLE WITH VOLTAGE ADJUST RHEOSTAT. Step 1. Check for sensing voltage at terminals E1, E2, and E3. If sensing voltage is not present, repair wiring. If sensing voltage is present, proceed to step 2.
- Page 38 Table 5-3. Troubleshooting Chart - Continued. MALFUNCTION TEST OR INSPECTION CORRECTIVE ACTION 4. VOLTAGE HIGH AND CONTROLLABLE WITH VOLTAGE ADJUST RHEOSTAT - Continued. Step 3. Check that the Voltage Adjust Potentiometer (R1) resistance is not too low. If the Voltage Adjust Potentiometer resistance is too low, replace potentiometer with one of the proper value.
- Page 39 Step 1. Verify that exciter/generator field requirements are not in excess of voltage regulator capability. If regulator application is incorrect for regulator, contact Basler Electric. If regulator application is within regulator limits, proceed to step 2. Step 2. Verify that input voltage at terminals 3 and 4 is of the correct value.
- Page 40 Table 5-3. Troubleshooting Chart - Continued. MALFUNCTION TEST OR INSPECTION CORRECTIVE ACTION 6. POOR REGULATION - Continued. Step 4. Check that the generator output waveform is not distorted due to harmonic content (Regulator senses average voltage; meter may be indicating RMS values.) If this condition exists, consult the generator manufacturer.
- Page 41 8. VOLTAGE RECOVER SLOW WITH LOAD CHANGE. Step 1. Verify that the correct regulator is being used for the application. If the incorrect regulator is being used, contact Basler Electric. If the correct regulator is being used, proceed to step 2.
- Page 42 Table 5-3. Troubleshooting Chart - Continued. MALFUNCTION TEST OR INSPECTION CORRECTIVE ACTION 8. VOLTAGE RECOVER SLOW WITH LOAD CHANGE - Continued. Step 3. Verify that the generator frequency is stable. If the frequency is unstable, consult with the governor manufacturer. If the frequency is stable, proceed to step 4.
- Page 43 Table 5-3. Troubleshooting Chart - Continued. MALFUNCTION TEST OR INSPECTION CORRECTIVE ACTION 11. PARALLEL GENERATORS DO NOT DIVIDE REACTIVE KVAR LOAD EQUALLY. (Circulat- ing Reactive Current Between Generators. Step 1. Verify that the tap on R25 is not set to the minimum position. If the tap is set to the minimum position, adjust R25 to obtain the required droop.