POWER SUPPLY OVERCURRENT FAULT
2440 Service
IN THE EVENT OF A SHORTED LOAD ON AN UNREGULATED VOLTAGE SUPPLY, THE
POWER SUPPLY WILL GO INTO THE “CHIRP” MODE. IT CONTINUALLY STARTS UP AND
SHUTS DOWN IN A REPEATED MANNER AS THE OVER-CURRENT SENSE CIRCUIT
DETECTS THE
EXCESSIVE SECONDARY
LOADING.
THE VOLTAGE WAVEFORM
PRESENT ON THE UNREGULATED VOLTAGE LINES GIVES AN INDICATION OF WHETHER
THE SECONDARY IS EXCESSIVELY LOADED. CHECK THE W AVEFORMS AT THE ZERO
OHM RESISTORS INDICATED IN THE ACCOMPANYING COMPONENT LOCATION FIGURE
FOR AN INDICATION OF EXCESSIVE LOADING. A SHORTED SECONDARY CIRCUIT IS
IDENTIFIED BY A MUCH SMALLER VOLTAGE WAVEFORM THAN SEEN ON A GOOD
SECONDARY (SEE ACCOMPANYING WAVEFORM ILLUSTRATION).
NOTE
A SHORT ON THE + 5 VD SUPPLY WILL BLOW FUSE F269.
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6330-56A
REV NOV 1988
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Summary of Contents for 2440
Page 4: ......
Page 12: ......
Page 38: ......
Page 91: ...Theory of Operation 2440 Service 3 49 Figure 3 5 Simplified CCD architecture ...
Page 120: ...Theory of Operation 2440 Service Figure 3 10 DC Restorer 3 78 ...
Page 130: ...Theory of Operation 2440 Service 3 88 ...
Page 136: ...Theory of Operation 2440 Service Figure 3 15 PWM Regulator and Inverter 3 94 ...
Page 138: ...Theory of Operation 2440 Service Figure 3 16 PWM switching waveforms 3 96 ...
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Page 322: ......
Page 419: ......
Page 423: ...2440 Service Figure 9 4b 2440 Block diagram part 2 6330 27 BLOCK DIAGRAM PART 2 ...
Page 427: ......
Page 428: ...2440 Service WAVEFORMS FOR DIAGRAM 1 6 2 8 5 3 2 ...
Page 429: ......
Page 432: ...2440 Service WAVEFORMS FOR DIAGRAM 2 BUS ISOLATED 6 6 0 3 4 9 ...
Page 433: ...WAVEFORMS FOR DIAGRAM 2 ...
Page 439: ......
Page 445: ......
Page 450: ...2440 Service WAVEFORMS FOR DIAGRAM 8 6603 27 ...
Page 455: ...W A V EFO R M S FOR D IAG RAM 11 WAVEFORMS FOR DIAGRAM 11 6603 29 ...
Page 458: ...WAVEFORMS FOR DIAGRAM 12 ...
Page 463: ...WAVEFORMS FOR DIAGRAM 14 ...
Page 471: ... C N i u i t e x r 4 j u J l i 1 i 6 28 5 44 WAVEFORMS FOR DIAGRAM 18 ...
Page 476: ...WAVEFORMS FOR DIAGRAM 20 ...
Page 490: ...YES ...
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Page 494: ......
Page 499: ...YES ...
Page 501: ......
Page 502: ...2440 Service FIG 1 C A B IN E T ...
Page 503: ......
Page 510: ...2440 Service SISSVHO Z Old ...
Page 511: ......
Page 512: ...A12 2440 Service F IG 3 C IR C U IT BOARDS ...
Page 513: ......
Page 517: ...10 16 R E V J U L 1993 Replaceable Mechanical Parts ...
Page 518: ...2440 Service ...
Page 519: ...FIG 4 L V H V PWR SUPPLY ...
Page 520: ...FIG 5 ACCESSORIES 2440 Service ...
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