Vanguard Instruments EZCT, Operating Procedures Manual

Page 1: ...PERATING PROCEDURES for the EZCT and EZCT 10 Digital Current Transformer Tester Vanguard Instruments Co Inc 1520 S Hellman Ave Ontario California 91761 TEL 909 923 9390 July 2005 FAX 909 923 9391 REV...

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Page 3: ...be off line and fully isolated Always ground the EZCT and EZCT 10 to a substation ground before connecting the test cables to a transformer Precaution with High Test Voltage Because the EZCT can prod...

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Page 5: ...EZCT Printer Paper 11 5 0 EZCT CABLE CONNECTIONS 12 6 0 OPERATING PROCEDURES 15 6 1 Run Test Procedure 15 6 1 1 Run Excitation and Ratio test 15 6 1 2 Run Ratio Only Test 21 6 2 EZCT Test Record ID 2...

Page 6: ...35 Table 14 Computer Interface Procedures 36 Table 15 Set Clock Procedures 37 Table 16 Set Knee Point Marker Procedures 38 Table 17 Print Impedance Procedures 39 Table 18 EZCT Diagnostic Procedures 41...

Page 7: ...ration only requires connecting the test leads to the current transformer primary and secondary windings and following the test sequence displayed on the LCD Knee point voltages IEEE 45 IEEE 30 ANSI 1...

Page 8: ...l features The only difference is that the EZCT 10 has more output current on the 50Vac and the 200Vac test voltages The EZCT test voltage and current output ranges are 50Vac 2A 200Vac 2A 1200Vac 1 2A...

Page 9: ...0 degree DISPLAY Backlit LCD 4 lines by 20 characters CONTROLS Keypad 10 alpha numeric keys and 6 function keys PRINTER Thermal printer prints on 4 5 inch wide thermal paper COMPUTER INTERFACE RS 232C...

Page 10: ...uracy 1 0 degree DISPLAY Back lit LCD 4 lines by 20 characters CONTROLS Keypad 10 alpha numeric keys and 6 function keys PRINTER Thermal printer prints on 4 5 inch wide thermal paper COMPUTER INTERFAC...

Page 11: ...enced to a functional description in Table 3 0 which describes the purpose of each item on the control panel Although the purpose of these controls and the display may seem obvious users should become...

Page 12: ...60Hz I O Input power connector with third wire safety ground and 20A built in circuit breaker 7 no marking AC receptacle 8 GROUND Ground Stud 9 RS 232C Connector 9 pin Serial interface port connector...

Page 13: ...ctional description in Table 4 0 which describes the purpose of each item on the control panel Although the purpose of these controls and the display may seem obvious users should become familiar with...

Page 14: ...0 60Hz I O Input power connector with third wire safety ground and 20A built in circuit breaker 7 no marking AC receptacle 8 GROUND Ground Stud 9 RS 232C Connector 9 pin Serial interface port connecto...

Page 15: ...C o n t r a s t s w i t c h o n c e P a p e r w i l l a d v a n c e f r o mp r i n t e r P r e s s P a p e r C o n t r a s t s w i t c h o n c e p a p e r w i l l m o v e b a c k w a r d i n t o p r i...

Page 16: ...ng any test cables The EZCT is supplied with a 20 foot X test cable and a 35 foot H cable Only the X cable connection is required to run the current transformer excitation test The H and X cable conne...

Page 17: ...Operating Procedures EZCT and EZCT 10 13 Figure 4 Connection to CTs on Wye Transformer Figure 5 Connection to CTs on a Delta Transformer...

Page 18: ...Operating Procedures EZCT and EZCT 10 14 Figure 6 Typical EZCT Connection to Multiple CTs...

Page 19: ...e is lowered to zero or because of the CT excitation curve characteristics The Knee point voltages using IEEE 45 IEEE 30 ANSI 10 50 standards are calculated and printed on the tabulated report The CT...

Page 20: ...R A T I O T E S T m e n u w i l l appear 5 8 Run the transformer ratio test by pressing key 1 YES 5 9 To have the EZCT calculate the percentage error enter the transformer nameplate ratio by pressing...

Page 21: ...4 None Wait for the printer to finish printing the test report 5 15 Press key 1 to keep the test results in working memory Continue on 5 16 NOTE If the EZCT memory contains test data f r o ma p r e v...

Page 22: ...d in FLASH EEPROM 5 19 Press the STOP key to return to the main menu 5 20 None The user selected not to save the test record a reminder message is displayed 5 21 Press key 2 to save record Continue on...

Page 23: ...Operating Procedures E Z C T a n dE Z C T 1 0 19 Figure 7 Typical EZCT Tabulated Report Printout Phase angle and measurement CT Turns ratio Test Results Knee Point Voltage ANSCI 10 50...

Page 24: ...Operating Procedures E Z C T a n dE Z C T 1 0 20 Figure 8 Typical EZCT Excitation Graph Knee Point Marker...

Page 25: ...report is shows in Figure 9 Table 6 Run Ratio Only Test STEP ACTION DISPLAY 6 1 None EZCT Main menu 6 2 Begin RUN TEST procedure Press key 1 RUN TEST on the MAIN MENU 6 3 Select Ratio Only Test by pre...

Page 26: ...s ratio test 6 7 P r e s st h e E N T E R k e yt oa c c e p tt h e ratio 6 8 Press key 1 YES to print the test report 6 9 None Wait for the printer to finish printing the test report 6 10 Press key 1...

Page 27: ...ved in FLASH EEPROM 6 14 Press the STOP key to return to the Main menu NOTE A typical test contains an excitation and turns ratio test A record may contain 10 tests An EZCT will store 128 records This...

Page 28: ...me using the alpha numeric keypad When finished press ENTER to store the data and go to the S T A T I O N i d e n t i f i c a t i o n s c r e e n 7 5 Enter the utility STATION name using the alpha num...

Page 29: ...tore the data and go to the C O MME N T S i d e n t i f i c a t i o n s c r e e n 7 10 Enter test COMMENTS using the alpha numeric keypad When finished press ENTER to store the data and go to the O P...

Page 30: ...manually entering the header information via the keypad T h e f o l l o w i n g p r o c e d u r e p r i n t s a l l t h e t e s t r e c o r d I D s s t o r e d i n t h e E Z C T s m e m o r y Table 8...

Page 31: ...Operating Procedures E Z C T a n dE Z C T 1 0 27 Figure 10 Test Record ID Directory Printout...

Page 32: ...ng them to the EZCT Table 9 Load Test Record ID Directory Procedure STEP ACTION EZCT DISPLAY 9 1 On the MAIN MENU Press key 2 SETUP to go to the Setup menu options shown at right 9 2 P r e s s k e y 1...

Page 33: ...TUP MENU options shown at right 10 2 P r e s s k e y 3 t o s e l e c t R E S T O R ER E C O R D 10 3 Press key 1 to restore a record 10 4 Press key 1 to enter the record number 10 5 Enter the record n...

Page 34: ...sing the built in thermal printer If more than one test is included in a test record the excitation curves will be combined and printed on one graph The user can print test record residing in EZCT wor...

Page 35: ...Operating Procedures E Z C T a n dE Z C T 1 0 31 F i g u r e1 1T y p i c a l E Z C T A b b r e v i a t e d T a b u l a t e dR e s u l t sP r i n t O u t...

Page 36: ...Operating Procedures E Z C T a n dE Z C T 1 0 32 Figure 12 Typical Graphic Results Print Out With Multiple Excitation Curves...

Page 37: ...ey 3 RESTORE RECORD 12 3 Press key 2 DIRECTORY 12 4 Press key 1 FULL DIRECTORY to generate a list of all the records stored in memory Press key 2 SHORT DIRECTORY to generate a list of the last 10 reco...

Page 38: ...Operating Procedures E Z C T a n dE Z C T 1 0 34 Figure 13 Typical Test Record Directory Printout...

Page 39: ...lay press key 1 to erase a single record Go to step 13 6 to erase all test records 13 5 Enter record number of the record to be deleted then press the ENTER key to confirm Press the ENTER key again to...

Page 40: ...l the EZCT to run any test available from the Front Panel Table 14 Computer Interface Procedures STEP ACTION EZCT DISPLAY 14 1 On the MAIN MENU press key 2 SETUP to select the SETUP MENU options shown...

Page 41: ...ect the SETUP MENU options shown at right 15 2 Press key 4 NEXT PAGE 15 3 Press key 2 SET TIME 15 3 Enter the month day year hour minute and seconds for the real time clock The display will now return...

Page 42: ...ISPLAY On the MAIN MENU press key 2 SETUP to select the SETUP MENU options shown at right 16 1 Press key 4 NEXT PAGE 16 2 Press key 3 KNEE POINT MARKER 16 3 Press key 1 2 or 3 to select the preferred...

Page 43: ...edures Table 17 Print Impedance Procedures STEP ACTION EZCT DISPLAY 17 1 On the MAIN MENU press key 2 SETUP to select the SETUP MENU options shown at right 17 2 Press key 4 NEXT PAGE 17 3 Press key 4...

Page 44: ...Operating Procedures E Z C T a n dE Z C T 1 0 40 Figure 14 Tabulated Report with Impedance Print Out...

Page 45: ...th pairs of X1 and X2 cables must be connected to the excitation voltage Vx and the H1 H2 cables must be connected to sense the Vh voltage in order for this mode to work properly Table 18 EZCT Diagnos...

Page 46: ...n on X voltage 2 Cannot saturate CT Excitation voltage range is too low Turn voltage knob to zero and change voltage selection 3 See voltage on display but current reading remains at 0A Open connectio...

Page 47: ...43 1520 S Hellman Ave Ontario CA 91761 USA Phone 909 923 9390 Fax 909 923 9391 Website http www vanguard instruments com EZCT 07 13 06 OAK...