Megger TTR20, Instruction Manual

Page 1: ...r Turn Ratio Test Set Catalog Nos TTR20 and TTR20 1 TTR20 DISCONTINUED High Voltage Equipment Read the entire manual before operating Aparato de Alto Voltaje Antes de operar este producto lea este manual enteramente M 2621 Van Buren Ave Norristown PA 19403 2329 610 676 8500 www megger com ...

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Page 3: ...TTR20 and TTR20 1 Handheld TTR Transformer Turn Ratio Test Set Instruction Manual ...

Page 4: ...t to change without notice WARRANTY Products supplied by Megger are warranted against defects in material and workmanship for a period of one year following shipment Our liability is specifically limited to replacing or repairing at our option defective equipment Equipment returned to the factory must be shipped prepaid and insured This warranty does not include batteries lamps or other expendable...

Page 5: ... Connectors 10 Connectors 10 4 SETUP CONNECTIONS AND OPERATION 11 General Instructions 11 Transformers 11 Single Phase Two Winding Transformers 12 Distribution Transformers with Two Secondary Windings 12 Three Phase Two Winding Transformers 16 Three Phase Three Winding Transformers 16 Current Transformers CTs 16 General Operating Procedure 20 Description of Menus and Test Screens 20 Use with the O...

Page 6: ...ery Replacement 29 Troubleshooting 30 Error Messages 31 Repair 33 APPENDIX A SPECIFICATIONS 35 Electrical 35 Environmental Conditions 37 Physical Data 37 APPENDIX B ORDERING INFORMATION SPARE PARTS LIST 39 APPENDIX C CONNECTIONS AND VECTOR VOLTAGE DIAGRAMS 41 ...

Page 7: ...ransformer 15 Figure 4 7 Setup for Testing X1 X3 Winding of Distribution Transformer 15 Figure 4 8 Setup for Testing Unmounted Current Transformer 18 Figure 4 9 Setup for Testing Taps on Multiple Tap CT 18 Figure 4 10 Setup for Testing BCT Mounted on Single Phase Two Winding Transformer 19 Figure 4 11 TTR20 Opening Display Screen 20 Figure 4 12 Start Test Screen 21 Figure 4 13 Test in Progress Scr...

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Page 9: ...e with the requirements of the IEEE C57 12 90 2013 standards For three phase transformers the test set is connected to each of the three phases of the transformer to be tested and measurements are made on a phase by phase basis Turn ratio phase displacement polarity and excitation current are displayed on a large LCD Transformer excitation current helps to detect transformer shorted turns or an un...

Page 10: ...uding physical damage from faults deteriorated insulation contamination and shipping damage A Transformer Turns Ratio Test Set such as the TTR20 can directly measure the turns ratio of single phase transformers as well as three phase transformers Deviations in these measurements will quickly indicate problems in transformer windings and in the magnetic core circuits If a transformer ratio deviates...

Page 11: ... of the test signals at A D converter inputs A D converter is used to convert the analog measurement signals to their digital replica The converted output digital signals are applied to CPLD complex programmable logic device and then are transferred to microprocessor The microprocessor is the main part of the TTR test set It provides proper timing sequence of operation gathers and calculates the t...

Page 12: ...ocate several types of problems within single and three phase transformers It is used to determine the no load accuracy of CTs and PTs and also determine the need to further test faulty CTs and PTs The TTR20 applies voltage to the high voltage winding of a transformer and accurately measures the resulting voltage from the low voltage winding The ratio of voltages is directly proportional to turns ...

Page 13: ...presentative giving a detailed description of the damage This instrument has been thoroughly tested and inspected to meet rigid specifications before being shipped It is ready for use when set up as indicated in this manual Safety First Be sure to read the safety information in Chapter 2 thoroughly and observe all safety precautions and recommendations How to Use This Manual Typographic Convention...

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Page 15: ...ect test leads from power equipment before attempting to disconnect them at the test set The ground connection must be the first made and the last removed Any interruption of the grounding connection can create an electric shock hazard Any repair or component replacement must be performed by qualified service personnel Safety Requirements Megger has made formal safety reviews of the initial design...

Page 16: ...and High Power Testing for additional information If the test equipment is operated properly and all grounds correctly made test personnel need not wear rubber gloves As a routine safety procedure however some users require that rubber gloves be worn not only when making connections to the high voltage terminals but also when manipulating the controls Megger considers this an excellent safety prac...

Page 17: ... either activate or de activate the backlight It will remain ON for a period of three minutes without activity Power ON Switch Press this switch to turn the TTR20 on Power OFF Switch Press this switch to turn the TTR20 off DISPLAY SCREEN LCD displays menus and test information KEYPAD 4 button keypad for entering menu selections and navigating through the various screens Figure 3 1 TTR20 Display Co...

Page 18: ...sformer The plug and receptacle are keyed to prevent the cable from being inserted incorrectly and to make certain that the correct cable is used TTR20 1 uses metal connectors The discontinued TTR20 used plastic connectors RS 232 PRINTER A DB 9 male connector for connecting a printer or to upload data in real time to a PC using HyperTerminal TEST CABLE INPUT Metal Connector for TTR20 1 PRINTER ...

Page 19: ...ransformer Check that a lead set connected is labeled for TTR20 test set operation The TTR20 has been designed to test a variety of transformers such as Single phase Three phase one phase at a time CTs PTs and Voltage Regulators Do not leave the TTR20 test set exposed below 50 F or above 1300 F 200 C or above 550 C for more than 2 hours Such conditions will lead to shortened service life of batter...

Page 20: ...n check the lead connections Distribution Transformers with Two Secondary Windings The TTR20 may test the turn ratios of distribution transformer secondary windings one at a time Perform the following setup procedure for single phase distribution transformer with two secondary windings 1 Connect the test lead set to the TEST CABLE receptacle of the TTR20 test set Make sure that the connector is fu...

Page 21: ...e windings is normal sign is displayed in front of the turns ratio test result See Figure 4 7 Figure 4 1 Setup for Testing Single Phase Transformer Figure 4 2 Setup for Testing Single Phase Autotransformer TTR20 AUTOTRANSFORMER H1 LEAD X1 LEAD H2 LEAD X2 LEAD H1 X1 H2 X2 TTR20 H1 LEAD H2 LEAD H1 H2 X1 X2 X1 LEAD X2 LEAD TRANSFORMER ...

Page 22: ...ulator Figure 4 4 Setup for Testing Single Phase Type B Inverted Design Step Voltage Regulator TTR20 H1 LEAD H2 LEAD X2 LEAD X1 LEAD S SOURCE RAISE DIRECTION SERIES WINDING L LOAD SHUNT WINDING SL COMMON L R TTR20 H1 LEAD S SOURCE SHUNT WINDING SL COMMON SERIES WINDING L R LOAD RAISE DIRECTION L X1 LEAD H2 LEAD ...

Page 23: ...6 Setup for Testing X3 X2 Winding of Distribution Transformer H2 and X2 Grounded Figure 4 7 Setup for Testing X1 X3 Winding of Distribution Transformer TTR20 H1 H2 H1 LEAD H2 LEAD X1 LEAD X2 LEAD X1 X2 X3 Remove Ground Connection TTR20 H1 H2 H1 LEAD H2 LEAD X1 LEAD X2 LEAD X1 X2 X3 TT20 Exc Voltage Oscillator H1 H2 H1 LEAD H2 LEAD X1 LEAD X2 LEAD X1 X2 X3 ...

Page 24: ...pe of transformers has primary secondary and tertiary windings Primary and secondary windings are tested as a regular three phase two winding transformer To test tertiary winding perform the following setup procedure 1 Connect the test cables to the test set 2 Connect the clips marked H1 and H2 of the test lead to the phase being tested high voltage winding terminals of the transformer under test ...

Page 25: ...ow current X winding may result in damage to the CT NOTES 1 The TTR20 may supply up to 100 mA of excitation current 4 digit resolution The TTR20 will automatically select the appropriate test voltage 8 V 1 5 V or 0 5 V when testing CTs Some current transformers with turn ratio of 50 5 and less may require more than 100 mA of excitation current when excited from 0 5 V source These CTs can not be te...

Page 26: ...Figure 4 8 shows the setup for testing unmounted current transformers Figure 4 9 shows the setup for testing the taps on a multiple tap CT Figure 4 8 Setup for Testing Unmounted Current Transformer Figure 4 9 Setup for Testing Taps on Multiple Tap CT TTR20 X1 LEAD X1 LEAD H1 LEAD X1 LEAD X1 X2 X3 X4 X5 TRANSFORMER H1 H2 POLARITY DOT X1 LEAD H1 CT H1 LEAD X1 X2 H2 LEAD H2 X2 LEAD BUS OR USE HEAVY G...

Page 27: ... The test can be performed without removal of the BCT from the equipment Connect the TTR20 to BCT as shown in Figure 4 10 NOTES 1 Expect that polarity of the windings is normal sign is displayed in front of the turns ratio test result 2 A jumper lead is not supplied with the TTR20 Figure 4 10 Setup for Testing BCT Mounted on Single Phase Two Winding Transformer BCT POLARITY MARKER TYP X1 LEAD H1 L...

Page 28: ... the menus and test screens in Figures 4 11 through 4 14 are for illustrative purposes only The TTR20 test set menus and test screens are operated by using the keypad On power up the test set performs a self test check and all hardware and software variables are initialized Opening Display Screen The LCD displays the opening screen Figure 4 11 as the test set performs a diagnostic self check of th...

Page 29: ...ers The remaining battery capacity is enough for approximately one hour of operation If battery level is below 5 the message REPLACE BATTERY UNIT WILL TURN OFF appears on the screen In 10 sec the TTR20 shuts down Replace the batteries six AA size replaceable alkaline batteries before further attempting to initiate the TTR20 operation Start Test Screen After a successful self test check the START T...

Page 30: ...of the test the TEST RESULTS screen Figure 4 14 appears Figure 4 14 TTR20 Test Result Screen The TEST RESULTS screen displays the test voltage used for the test the measured turns ratio the tested winding polarity for in phase or normal polarity and for out of phase or reversed polarity and the tested winding excitation current From this screen the test results may be printed out on the optional p...

Page 31: ...en power on the TTR20 first Pressing after the first test result will provide a header and the data on the print out Each subsequent press of enter will print results data only If a new header is needed pressing the key will print a new header Then the enter key will need to be pressed to print the data that is presently on the screen Printing headers and data may be repeated as many times as need...

Page 32: ... Configuration To print a paper copy of the existing printer settings While holding down the On Line switch turn on the printer The following list will print factory default settings shown Figure 4 16 Printer Configuration Printout ...

Page 33: ...onfiguration mode For each group of switches press the FEED switch if all the settings are okay Press the ON LINE switch if a setting needs to be changed At an individual setting press the FEED switch if it is okay and press ON LINE to change that setting HyperTerminal Configuration The following is the HyperTerminal configuration Baud 19 200 Data Bits 8 Parity None Stop Bits 1 Flow Control None ...

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Page 35: ... with a soft dry cloth taking care not to scratch the display screen cover Clean the cables and mating panel receptacles with isopropyl or denatured alcohol applied with a clean cloth Calibration Check A complete performance and calibration check should be made at least once every year This will ensure that the TTR20 test set is functioning and calibrated properly over the entire measurement range...

Page 36: ...eing connected Such connection cause an impedance mismatch and as a result of the mismatch the displayed turns ratio reading is not exactly 1 1 as it may be expected A customer should be aware that a functional test is not a real transformer turns ratio test Due to the intrinsic and inevitable impedance mismatching the TTR20 functional test readings may be from 0 9980 to 1 0020 The TTR20 functiona...

Page 37: ... flat bottom portion of battery should be placed against a battery holder spring The batteries should be installed in series See a battery holder for proper polarity and battery installation orientation 4 Connect a battery strap back to the battery holder Install the battery holder into the compartment 5 Replace the battery compartment door and secure it with screws 6 Turn on TTR20 It should displ...

Page 38: ...N POSSIBLE CAUSE Display stays blank after POWER switch is turned on Battery is discharged Contrast potentiometer not adjusted Defective display or electronics Any error message on the screens See ERROR MESSAGES section Test results erratic Defective test leads open circuit poor connection Problem in test specimen poor connection Problem in TTR20 measuring circuit Incorrect connection of leads Inc...

Page 39: ...than 5 Unit will turn off in 10 sec Replace all six batteries After the batteries are replaced continue testing The test error messages may appear on the screens during testing of transformer The Table 5 3 below shows the messages Table 5 3 Test Error Messages Error Message Description of error and action required REPLACE BATTERY UNIT WILL TURN OFF The remaining battery capacity is less than 5 Uni...

Page 40: ... appear on the screens during printing functions The Table 5 4 below shows the message Table 5 4 Miscellaneous Message Error Message Description of error and action required PRINT ERROR There was an error during printing a report Try again See Table 5 1 If failed contact the factory for repair When an error message appears on a screen indicating an abnormal operating condition verify the condition...

Page 41: ...prepaid and insured and marked for the attention of the Repair Department Please indicate all pertinent information including problem symptoms and attempted repairs The catalog number and serial number of the test set should also be specified Pack the TTR test set including all cables in a carton original shipping carton if available with adequate dunnage in accordance with best commercial practic...

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Page 43: ...n Degree II Regulatory Compliance IEC 61010 1 Environmental Protection Dust and shower protection to IP54 Output Test Voltage and Current 8 V rms for testing distribution or power transformers and PTs 0 5 1 5 or 8V ac rms for testing CTs Test Frequency 55Hz internally generated providing a universal 50 60 Hz test set Loading of Test Transformer Less than 0 1 VA Measuring Ranges Turns ratio 0 8 1 t...

Page 44: ...t value Current rms 5 of reading 0 5 mA Measurement Method In accordance with ANSI IEEE C57 12 90 2013 and IEC 60076 1 2000 Transformer Winding Phase Relationship ANSI C57 12 70 2011 CEI IEC 76 1 2011 Measuring Time Less than 5 seconds Display Wide temperature range LCD module adjustable back lighting 128 x 64 dots 21 characters by 8 lines ...

Page 45: ...connection The cable is included in optional printer package Data exchange rate up to 57 6 Kbaud for the field firmware upgrading and 19 2 Kbaud for test report printing on the optional serial printer Environmental Conditions Operating temperature range 5 to 130 F 20 to 55 C Storage temperature range 55 to 140 F 50 to 60 C Relative humidity 0 to 90 noncondensing operating 0 to 95 noncondensing sto...

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Page 47: ...s Combined test leads set X H winding 12 ft 3 6 m 2007 713 12 Combined test leads set X H winding 20 ft 6 1 m 2007 713 20 Combined test leads set X H winding 33 ft 10 1 m 2007 713 33 Test Leads TTR20 Discontinued TTR20 Lead Set 1 8 m 6 ft 35938 TTR20 Lead Set 3 6 m 12 ft 35942 TTR20 Lead Set 6 m 20 ft 36013 TTR20 Lead Set 10 m 33 ft 36042 Printer package including battery line power serial thermal...

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Page 49: ... external jumper if required After phase A test is complete reconnect the test leads to phase B Put an external jumper if required After phase B test is complete reconnect the test leads to phase C Put an external jumper if required Compare the measured test results to the calculated turns ratios NOTE Three phase transformer may be tested in any order For example phase C then phase A and then phas...

Page 50: ...tion s to ground case of T type transformer on H or X side should be removed before testing a transformer 2 Expect that polarity of the windings is normal sign is displayed in front of the turns ratio test result Table C 1 ANSI Transformer Winding Phase Relationship Winding Connection Winding Tested IEC Vector Group High Voltage Winding H Low Voltage Winding X External Jumpers Phase tested High Vo...

Page 51: ...nal terminals on HV transformer winding X1 X2 X3 External terminals on LV transformer winding H0 External neutral terminal on HV transformer winding X0 External neutral terminal on LV transformer winding Inaccessible neutral point on HV or LV transformer winding VH Nameplate voltage rating line to line of HV transformer winding VX Nameplate voltage rating line to line of LV transformer winding A B...

Page 52: ...marks 1 1 1ph0 1 H1 H2 X1 X2 Single phase transformer 2 1 1ph6 1 H1 H2 X2 X1 Single phase transformer 3 Dd0 A B C H1 H3 H2 H1 H3 H2 X1 X3 X2 X1 X3 X2 4 Dd6 A B C H1 H3 H2 H1 H3 H2 X3 X1 X1 X2 X2 X3 5 Dyn1 A B C H1 H3 H2 H1 H3 H2 X1 X0 X2 X0 X3 X0 Neutral accessible on wye winding 6 Dyn7 A B C H1 H3 H2 H1 H3 H2 X0 X1 X0 X2 X0 X3 Neutral accessible on wye winding 7 YNyn0 A B C H1 H0 H2 H0 H3 H0 X1 X...

Page 53: ...3 Neutral accessible both wye windings 9 YNd1 A B C H1 H0 H2 H0 H3 H0 X1 X2 X2 X3 X3 X1 Neutral accessible on wye winding 10 YNd7 A B C H1 H0 H2 H0 H3 H0 X2 X1 X3 X2 X1 X3 Neutral accessible on wye winding 11 Dy1 A B C H3 H2 H1 H3 H2 H1 H1 H3 H2 H2 H1 H3 H3 H2 H1 X1 X3 X2 X1 X3 X2 No accessible neutral on wye winding 12 Dyn5 A B C H1 H3 H2 H1 H3 H2 X3 X0 X1 X0 X2 X0 Neutral accessible on wye windi...

Page 54: ...1 X1 X2 X2 X3 No accessible neutral on wye winding 15 Dyn11 A B C H1 H3 H2 H1 H3 H2 X0 X3 X0 X1 X0 X2 Neutral accessible on wye winding 16 Dy11 A B C H3 H2 H1 H3 H2 H1 H1 H3 H2 H2 H1 H3 H3 H2 H1 X2 X3 X3 X1 X1 X2 No accessible neutral on wye winding 17 Dz0 A C B A C B H1 H3 H2 H1 H3 H2 X1 X3 X2 X1 X3 X2 No accessible neutral 18 Dz6 A C B A C B H1 H3 H2 H1 H3 H2 X3 X1 X1 X2 X2 X3 No accessible neut...

Page 55: ...essible neutral on high voltage winding 21 Yy0 A B C H1 H3 H2 H1 H3 H2 X1 X3 X2 X1 X3 X2 No accessible neutral both wye windings 22 YNy6 A B C H2 H0 H3 H0 H1 H0 H1 H2 H0 H2 H3 H0 H3 H1 H0 X2 X1 X3 X2 X1 X3 No accessible neutral on low voltage winding 23 Yyn6 A C B A C B H1 H3 H2 H1 H3 H2 X3 X1 X1 X2 X2 X3 No accessible neutral on high voltage winding 24 Yy6 A C B A C B H1 H3 H2 H1 H3 H2 X3 X1 X1 X...

Page 56: ...H1 X1 X2 X2 X3 X3 X1 No accessible neutral 27 Yzn5 A B C H1 H3 H2 H1 H3 H2 X3 X0 X1 X0 X2 X0 No accessible neutral on wye winding 28 Yz5 A B B C C A H3 H2 H1 H3 H2 H1 H1 H3 H2 H2 H1 H3 H3 H2 H1 X3 X1 X1 X2 X2 X3 No accessible neutral 29 Yzn7 A B C H1 H3 H2 H1 H3 H2 X0 X1 X0 X2 X0 X3 No accessible neutral on wye winding 30 Yz7 A B B C C A H3 H2 H1 H3 H2 H1 H1 H3 H2 H2 H1 H3 H3 H2 H1 X2 X1 X3 X2 X1 ...

Page 57: ...2 No accessible neutral 33 ZNy5 A C B A C B H1 H0 H2 H0 H3 H0 X3 X1 X1 X2 X2 X3 No accessible neutral on wye winding 34 Zy5 A C B A C B H3 H2 H1 H3 H2 H1 H1 H3 H2 H2 H1 H3 H3 H2 H1 X3 X1 X1 X2 X2 X3 No accessible neutral 35 ZNy11 A B B A C B H1 H0 H2 H0 H3 H0 X1 X3 X2 X1 X3 X2 No accessible neutral on wye winding 36 Zy11 A C B A C B H3 H2 H1 H3 H2 H1 H1 H3 H2 H2 H1 H3 H3 H2 H1 X1 X3 X2 X1 X3 X2 No...

Page 58: ...3 H0 X3 X1 X1 X2 X2 X3 Neutral accessible on wye winding 39 Yd5 A B C H3 H2 H1 H3 H2 H1 H1 H3 H2 H2 H1 H3 H3 H2 H1 X3 X1 X1 X2 X2 X3 No accessible neutral on wye winding 40 Yd7 A B C H3 H2 H1 H3 H2 H1 H1 H3 H2 H2 H1 H3 H3 H2 H1 X2 X1 X3 X2 X1 X3 No accessible neutral on wye winding 41 YNd11 A B C H1 H0 H2 H0 H3 H0 X1 X3 X2 X1 X3 X2 Neutral accessible on wye winding 42 Yd11 A B C H3 H2 H1 H3 H2 H1 ...

Page 59: ...B C H1 H3 H2 H1 H3 H2 X0 X2 X0 X3 X0 X1 Neutral accessible on wye winding 45 Dy3 A B C H3 H2 H1 H3 H2 H1 H1 H3 H2 H2 H1 H3 H3 H2 H1 X1 X2 X2 X3 X3 X1 No accessible neutral on wye winding 46 Dyn9 A B C H1 H3 H2 H1 H3 H2 X2 X0 X3 X0 X1 X0 Neutral accessible on wye winding 47 Dy9 A B C H3 H2 H1 H3 H2 H1 H1 H3 H2 H2 H1 H3 H3 H2 H1 X2 X1 X3 X2 X1 X3 No accessible neutral on wye winding 48 YNzn1 A B C H...

Page 60: ...winding 51 YNd3 A B C __ H1 H0 H2 H0 H3 H0 X3 X2 X1 X3 X2 X1 Neutral accessible on wye winding 52 YNd9 A B C __ H1 H0 H2 H0 H3 H0 X2 X3 X3 X1 X1 X2 Neutral accessible on wye winding 53 Yd3 A B C H3 H2 H1 H3 H2 H1 H1 H2 H3 H2 H3 H1 H3 H1 H2 X3 X2 X1 X3 X2 X1 No accessible neutral on wye winding 54 Yd9 A B C H3 H2 H1 H3 H2 H1 H1 H2 H3 H2 H3 H1 H3 H1 H2 X2 X3 X3 X1 X1 X2 No accessible neutral on wye ...