PASCO PI-9880, Инструкция по эксплуатации

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D C P r o g r a m m a b l e P o w e r S u p p l y B a s i c O p e r a t i o n
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Set Voltage Rotate Coarse knob to change the output voltage by 1.0 V per detent; rotate the Fine knob slowly
to change the voltage by 0.01 V per detent, or quickly to change the voltage by 0.04 V per detent.
By default the output voltage is limited to 18 V, but this limit may be set lower. If a load is connected to the
Power Supply, the highest allowable voltage may also be limited by the maximum-current setting, which is 1 A
by default. See “Maximum Values” below for instructions on setting these maximums.
Voltage and Current Display To switch the display from voltage to current, press (DISPLAY); the out-
put current appears on the display, and the Current LED lights. Press (DISPLAY) again to switch the display
back to voltage.
When current is displayed, rotating the Coarse and Fine knobs adjusts the voltage. Note that the current is not
regulated. If the load changes the voltage will remain constant at its set value, but the current will change.
In Constant DC mode you can set the display to cycle between voltage and current. Press and hold (SET)
while rotating the Coarse knob to set the cycle time in seconds (while you are making this adjustment, the Time
LED is lit and the display shows the cycle time); then release the button. The display alternates between current
and voltage at a rate determined by the cycle time that you set. Press
(DISPLAY) to pause the display on volt-
age or current; press again to restart alternating. To disable alternating display mode, press and hold
(SET) while rotating the knobs to set the cycle time to zero.
You can also press and hold (STOP) to reset both the cycle time and the voltage to zero.
Output Switch-off To temporarily switch off the output, press . The Voltage LED blinks quickly to indi-
cate that the actual output voltage is zero even though the voltage setting (which may not be zero) is displayed.
While the output is switched off, you can turn the Coarse and Fine knobs to adjust the voltage setting. Press
again to switch the output voltage back on.
Over-current If output current exceeds the maximum-current setting (see “Maxi-
mum Values” below), the output voltage drops to zero, the display reads OL (for “over-
load”), and Current LED flashes amber. Press
(START) to resume normal operation.
Reset Output and Display Press and hold (STOP) to set the voltage to zero
and set the display to show voltage. The output and display are also reset in this way if
you turn the Function knob and return it to Constant DC mode.
Maximum Values
By default, the Power Supply is set for a voltage limit of 18 V and a maximum current of 1 A. The Power Supply
will not allow its output to exceed the voltage limit, and it will turn off the output if it exceeds the maximum cur-
rent. To lower the maximum-allowable voltage or current, turn the Function knob to SET MAX. In this mode
you can also set the Power Supply to turn off the output after a specified time.
In SET MAX mode, the display shows maximum-value settings; the actual output voltage is always zero.
To prevent accidental damage to lab equipment, set an appropriate maximum voltage or current for the equipment that the
Power Supply will be used with.
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 Current 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.
Display reads OL if the
maximum current is
exceeded