PASCO PI-9877, Инструкция по эксплуатации

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Model No. PI-9877 Basic Operation
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Voltage Limit
When the Power Supply first enters SET MAX mode, the Voltage
LED blinks slowly and the display shows the voltage-limit setting. Rotate the Coarse
knob to change the voltage limit by 1.0 volt per detent; rotate the Fine knob slowly to
change it by 0.01 volt per detent, or quickly to change it by 0.04 volts per detent.
The voltage-limit setting cannot be higher than the Global Maximum voltage. See below for
instructions on setting the Global Maximum.
Maximum Current
Press (DISPLAY) to set the maximum current. The Cur-
rent LED blinks slowly and the display shows the maximum-current setting (1.05 A
by default). Rotate the Coarse knob to change the setting by 0.1 amp per detent; rotate
the Fine knob slowly to change the setting by 0.001 amp per detent.
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 Supply 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 dis-
play 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 dem-
onstration or display.
Global Maximum
The Global Maximum is a hidden feature that the instructor can use to securely set the
maximum-allowable voltage. 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 set-
tings.
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