THORLABS PM100A Quick Reference page 9

adjustment can also be automated by pressing the OK key. The scale control
menu item indicates the particular full scale value in Watts.
The scales end have a fixed 1 – 2 – 5 grid, therefore it is possible that the full scale
range may be higher than the power range. In such a case, when the power level
is exceeding the power range, the needle will deflect to the right stop and the
readout value will indicate 'HIGH'.
3.2.3.3 Wavelength Correction
λ
λ
Pressing the key leads to a wavelength menu with 8+1 individually configurable
sensor independent settings. The currently set operating wavelenght is indicated
by a following arrow ( ) and has focus when entering the menu. Select the
desired operating wavelength by navigating with the keys and confirming
λ
with OK. The key allows to exit without changing the operating wavelength.
To preconfigure or edit a wavelength item, navigate to it and keep the OK key
pressed until the last digit gets underlined. Set the desired wavelength with the
keys and confirm with OK.
When selecting a wavelength that is not applicable for the connected sensor a
warning sound will appear and the unit will keep the previous wavelength setting.
Wavelength setting in remote operation will overwrite the down to the right value.
3.2.3.4 Zeroing
Confirming the ZERO menu item with OK, the unit performs an automated zero
adjustment and from now on takes into account this zero level for the power
readout calculation. This feature is used to zeroing thermal sensors, performing
dark current adjustment on photodiode sensors or suppressing small ambient light
levels. When the initial power level is too high, a failure message will appear that is
prompting to cover the power sensor prior to zero adjustment.
When the PM100A detects "negative" power levels, additionally a ZERO! warning
will appear in the status indicator.
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