The PAM-2500 chlorophyll fluorometer can be configured for measurements of leaves and suspensions. In both cases, a flexible optical fiber guides modulated measuring light as well as actinic light to the sample, and collects the chlorophyll fluorescence.

Independent of configuration, the use of power LEDs results in high actinic intensities of up to 2000 μmol m-2 s-1 and single turn-over flash intensities up to 125,000 μmol m-2 s-1 at sample level. Additionally, the PAM-2500 features blue actinic light up to 800 μmol m-2 s-1 and an efficient far red light source.

For leaf measurements, the sample is positioned relative to the fiber by special leaf clips. The use of the light-sensing leaf clip 2030-B is particular advantageous as it permits deriving relative electron transport rates from PAR measurements and PS II photochemical yields, Y(II). Also, the 2030-B clip measures leaf temperature by a thermoelement.

To examine suspensions of isolated chloroplasts, algae or cyanobacteria, the fiberoptics is plugged in the special cuvette KS-2500. The cuvette can be used in combination with a magnetic stirrer and temperature control..