© 2016 Thorlabs GmbH
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PM320E
3.1.4 Range Setting
Depending on the used sensor, the PM320E provides:
·
up to 6 current related power measurement ranges, selectable manually or in auto ranging
mode
·
up to 3 voltage related power measurement ranges, selectable manually or in auto
ranging mode
·
4 voltage related energy measurement ranges, selectable manually only.
To select a range or switch to the auto-range mode, navigate to ‘Range’ button (single or dual
channel display) or select in the Setup display the ‘Power Range’ menu and click the button to
edit the range setting menu. Depending on the sensor type you can chose between several
power ranges and the auto-range mode either by turning the control knob or using the <Down>
and <Up> soft keys. The selected range is activated immediately. To leave the menu, press the
control knob or the <OK> soft key.
When power meter sensors are connected, the ranges will show in Watts, with energy sensors
in Joules. For the photodiode inputs the ranges can additionally be set in Amperes, for the
thermal head adapter and the pyroelectric head adapter in Volts.
3.1.5 Relative Power Measurement
This feature can be used to observe power drifts, adjust power to a certain level, or quickly
subtract ambient light.
Navigating to the direct access ‘
D
P’ button and clicking the multi-control knob toggles between
relative and absolute power measurement. When the relative power measurement is activated,
the header changes to ‘Delta Power’, the current power reading gets zeroed, the bar graph
goes to a zero middle position, the subtracted value gets indicated in the ‘
D
P’ menu. From now
on the main display and the bar graph are showing the difference to the subtracted power in W
or dBm with a one digit higher resolution. The sub display still shows the absolute power level.
A Range setting is still possible as described in the paragraph above.
