Figure; As 1767, Bs 148, Bs 5874, Cei 10 -1, En60156, Iec 156, Ip 295, Nfc; Γoct 6581, Sabs 555, Stas 286, Une21 And Vde 0370 Tests - Megger OTS 60AF Guia Del Usuario

Note:- At any time during a test sequence the right hand control key labelled STOP can be used to end
a test and return to the test option display screen. Similarly during printing the left hand key
labelled STOP can be used to stop the print function and return to the average breakdown
display screen.
AS 1767, BS 148, BS 5874, CEI 10-1, EN60156, IEC 156, IP 295, NFC 27, ΓOCT 6581, SABS 555,
STAS286, UNE 21 and VDE 0370 tests.
Note:- These specifications give the option of using spherical or mushroom shaped electrodes.
1. To commence, highlight the selected teston the main menu and press SELECT. The display
willappear similar to figure 7. Press the right hand key marked MENU to return to main menu.
Repeated pressing of the centre key labelled STIR MODE changes the stirring choice through
MAGNETIC, IMPELLER or NONE.
2 On pressing the START key, TEST 1 is initiated. The display appears similar to figure 8. The
display indicates that the initial stand time is being undertaken and time remaining is shown in
minutes and seconds.
3. After the initial stand time is complete the high voltage is switched on and applied to the oil
sample. The screen display appears similar to figure 9.
The display shows the voltage rising at the rate of 2kV/s being applied. This voltage rise
continues until breakdown occurs (or up to maximum). The number of the test in the sequence is
displayed together with the words 'IN PROGRESS'.
4. When breakdown occurs (or if the maximum voltage is reached) the test voltage is cut off, the
high voltage indicator light goes out and the test set begins its intermediate stirring period. The
stirrer rotates for a period of 1 minute and the previous breakdown voltage is retained on the
display. The display screen appears similar to figure 10.
Time remaining for stirring is displayed, alternating with the word 'STIRRING'.
5. When stirring has finished the display indicates that the intermediate standing period is being
undertaken. Time remaining is shown, alternating with the word 'STANDING'. The previous
breakdown voltage is retained on the display, which appears similar to figure 11.
6. The test voltage then begins to rise again as in step (2), this time for TEST 2, and the cycle of
events repeats.
7. For these specifications there are 6 consecutive tests. After the test voltage has been cut off on
the last test, the display shows the average breakdown voltage value from the 6 tests in the
sequence. The display appears similar to figure 11.
Note:- (1) NFC27, STAS286 and UNE21 test specifications differ from the above in that the last 5 of the
6 results are used to calculate the average and standard deviation. (2) The programme for the
BS 148 test sets a pass limit of 30 kV, as required by the specification for this standard.
The three control keys now assume different functions. Press the left hand key labelled VIEW to
sequentially display the breakdown voltage value of each individual test, followed by their standard
deviation value. If the automatic print option is pre-selected, the results will be printed automatically at
the conclusion of a test sequence. If not, press the centre key, labelled PRINT to obtain a print-out of the
results. When the printer is in operation the display shows 'PRINTING PLEASE WAIT'. Press the NEW
key to return to the start of the selected test, followed by the left hand START key to repeat a test
sequence, or the MENU key to return to the main menu.
Note:- At any time during a test sequence pressing the right hand key labelled STOP will end a test and
return to the test option display. Similarly during printing, the left hand key labelled STOP can be
used to stop the print function and return to the average breakdown display screen.
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