PASCO PI-9880 Power Supply - Manual (Page 23)

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While the Power Supply is operating in any mode, if the output current goes over the set maximum, the output
voltage will drop to zero and the Current LED will flash amber, and the display will show OL. Press
(START) to resume operation.
Automatic Time Off
Press (DISPLAY) again to set the Automatic Time Off feature. The Time LED blinks and the display shows
the countdown time in hours. Turn the Coarse and Fine knobs to set the time, then press (START) to start the
countdown. The Time LED is lit steadily to indicate that the countdown has started.
While the countdown is in progress, you can turn the Function knob to any position and operate the Power Sup-
ply in the normal way. To check the remaining time, return to SET MAX mode and press
(DISPLAY) twice
so that the Time LED is lit. To stop the countdown (while the remaining time is displayed), press and hold
(STOP).
When the countdown time has elapsed, the output voltage drops to zero and the display
reads OFF. To resume normal operation, press either button.
After setting the time, you must press (START) to start the countdown. The maximum setting is
99.99 hours (about 4 days). You can use this feature to automatically stop an unattended demon-
stration or display.
Global Maximum
The Global Maximum is a hidden feature that the instructor can use to securely set the maximum-allowable volt-
age. The Power Supply remembers the Global Maximum setting even after it is turned off and unplugged.
To set the Global Maximum, turn the Function knob to SET MAX. With the Voltage LED indicator blinking
slowly (if a different LED is on, press
once or twice), press and hold and together; while holding both
buttons, wait for the Voltage LED to start blinking fast, then turn the Coarse and Fine knobs to adjust the Global
Maximum voltage. This master setting overrides any previous maximum voltage settings.
Safety Feature: Before giving the Power Supply to students, you can set the Global Maximum to the highest necessary voltage
for the Power Supply’s intended use.
Display reads OFF after
Automatic Time Off