HP 7475A Plotter - Error Light Functions
Why the error light blinks every five seconds.
When the plotter is not active, the ERROR light will blink dimly approximately every five seconds. This indicates internal power supply calibration is being performed.
note:When the ERROR light is on but not blinking, it indicates the VIEW button has been pressed or the paper loading lever is in the PAPER LOAD position (pinch wheels up).
ISSUE: Other reasons why the error light would come on.
When the ERROR light is blinking brightly, it indicates the plotter has detected an Input/Output error (I/O) error, a paper moving error or an HP-GL error for which the error mask has been set. For a description of errors, refer to instructions IM, OE, and ESC.E in the Interfacing and Programming Manual.
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